Electric Vehicles Empowering the Construction of Green Sustainable Transportation Networks in Chinese Cities: Dynamic Evolution, Frontier Trends, and Construction Pathways

Abstract

As the global ecological environment faces serious challenges and extreme climate change threatens the survival of humankind, the promotion of green development has become the focus for all countries in the world. As one of the world’s major greenhouse gas emitters, China has put forward the “twin goals” of achieving carbon peaking and carbon neutrality and is committed to promoting the green and low-carbon transformation of its cities. As the core of economic and social development, cities are the main source of carbon emissions. In response to the dual challenges of carbon emission control and traffic growth, it is particularly important to promote the development of green transportation. With the acceleration of urbanization, urban traffic pollution is becoming more and more serious. As a zero-emission transportation mode, electric vehicles have become a key way to achieve the carbon peak and carbon neutrality targets. In order to deeply analyze the research status of electric vehicles in the field of the green and low-carbon transformation of urban transportation in China and to explore the research hot spots, evolution trends, and their roles and strategies in the construction of green transportation networks, this paper uses the CiteSpace, VOSviewer, and Tableau analysis tools to review and analyze the 2460 articles and reviews in the Web of Science Core Collection (WOS) and 2650 articles and reviews in the China National Knowledge Infrastructure (CNKI), including the “publication volume and publication trend”, “subject citation path”, “countries cooperation and geographical distribution”, “author cooperation and institution cooperation”, “keyword co-occurrence and keywords clusters”, and the “evolution trend of research hot spots in timeline”. The results show that: (1) Since 2010, the research focus on electric vehicles has gradually increased, and especially in the past three years, the number of such publications has increased significantly. (2) China holds the lead in research output regarding electric vehicles and related fields, but its international cooperation needs to be strengthened. (3) In recent years, the research has focused on “energy transformation”, “energy-saving technology”, “carbon emissions”, “battery recycling”, and other relevant topics. The promotion and development of electric vehicles will continue to usher in new opportunities concerning technological innovation, policy support, and market expansion. Finally, based on the research hot spots and evolution trends of electric vehicles in the field of urban green transportation and low-carbon transportation in China, this paper discusses the key paths and strategies for electric vehicles to promote the transformation of urban transportation in China to green and low-carbon types and looks forward to future research directions. The research in this paper can provide theoretical support and practical guidance for China to promote electric vehicles, build low-carbon cities, and realize green transportation. It is expected to act as a useful reference for relevant policy formulation and academic research.

1. Introduction

As global ecological damage is becoming increasingly serious, extreme climate change poses a great threat to the survival of mankind, and the contradiction between world economic development and the deterioration of the natural environment is becoming more and more prominent; thus, green development has become a focus for all countries in the world [1].

As one of the world’s major emitters of greenhouse gases, China has actively assumed international responsibility and proposed the “twin goals” of achieving carbon peaking and carbon neutrality [2,3]. The goals are not only a concrete action by China to deal with climate change, but are also important measures to promote urban green and low-carbon transformation. As the center of national and regional economic and social development, cities are one of the main sources of carbon emissions, which makes cities the important carrier for promoting low-carbon transformation and achieving high-quality economic and social development. Urban transportation is a significant source of urban carbon emissions; thus, under the dual challenges of achieving strict control of carbon emissions and meeting the increasing traffic demand, promoting green transportation is of great significance for facilitating the green and low-carbon transformation of transportation [4].

Green transportation plays an important role as one of the important ways to achieve the “twin goals”. There is no unified definition in the academic community regarding the concept and connotation of “green transportation”. As early as 1994, Canadian scholar Chris Bradshaw put forward the concept of the “green transportation hierarchy” [5]. Since then, green transportation has become a hot topic for scholars, both domestically and internationally. The scholars generally believe that green transportation represent a completely new concept of transportation development and city growth [6], which is the embodiment of people-oriented sustainable development in the transportation field. It aims to construct a diversified and comprehensive transportation system that coordinates the environment, resources, and society, with the goal of reducing traffic congestion, lowering environment pollution, decreasing greenhouse gas emissions, and promoting social equity [7,8,9,10,11]. Green transportation emphasizes the realization of low-carbon, environmentally friendly, and efficient development in transportation and reduces greenhouse gas emissions by optimizing the transportation structure, promoting clean energy, and improving transportation efficiency, which will not only help to achieve the goals, but also promote the sustainable development of cities [12].

With the rapid advancement of urbanization in China, urban traffic pollution has become more and more serious, which has been one of the major obstacles restricting the sustainable development of cities. Particularly in the field of transportation, especially urban transportation, the realization of the “twin goals” (carbon peaking and carbon neutralization) is facing severe challenges. Vehicle exhaust is one of the main sources of urban carbon emissions. According to relevant data, carbon dioxide emissions from the transportation industry account for about 10% of the total carbon emissions in the country [13]. Therefore, reducing the use of traditionally fueled vehicles is the key to reducing carbon emissions [14]. As a zero-emission transportation mode [15], electric vehicles provide many benefits, such as energy conservation, energy storage, and emission reduction. Promoting electric vehicles is an effective way to simultaneously ensure energy security and achieve the “twin goals” [16]. In view of this, the promotion of electric vehicles, the construction of low-carbon cities, and the realization of green transportation have become urgent issues.

In order to cope with the above challenges, the Chinese government has issued a series of policy measures. For instance, the Chinese government released a document titled, “Working Guidance for Carbon Dioxide Peaking and Carbon Neutrality in Full and Faithful Implementation of the New Development Philosophy” in September 2021 [17]. This document advocated for the vigorous development of new energy vehicles and promoted their deep integration with next-generation information technology and high-end equipment to form a green manufacturing system. Additionally, this document emphasized accelerating the construction of a “convenient, efficient and moderately advanced” charging and swapping network to provide favorable conditions for the usage of new energy vehicles. In October of the same year, the Chinese government also released the “Action Plan for Carbon Dioxide Peaking Before 2030” [18], which proposed vigorously supporting the key technology breakthrough of new energy vehicles (such as power batteries and energy storage technology) and promoting the demonstration and application of key technologies. Furthermore, it called for pilot projects in carbon peaking cities and encouraged innovation in electric vehicle application scenarios. These policies introduced by the Chinese government require that carbon peaking be integrated into the entire process and all aspects of economic and social development, with a focus on implementing key tasks such as green and low-carbon energy transformation and green and low-carbon transportation. This provides vast space and significant opportunities for China to build an “urban green transportation network”.

In recent years, an increasing number of scholars have begun paying attention to the research on “green transportation”. How to develop urban green transportation has become a hot topic in academia. Countries and international organizations like the United States, the United Kingdom, and the European Union boast the theoretical research results and practical experience that can be used for reference in the construction of green transportation networks [19]. At present, scholars at home and abroad mainly focus on research topics such as “decision making”, “lithium-ion battery”, “green and low-carbon”, “indicator system”, “carbon neutrality”, “carbon peak”, and “emission reduction” in the field of green transportation [20,21,22,23,24,25,26,27,28,29,30,31,32]. However, there are few comprehensive analyses achieved through bibliometrics, especially in the context of China’s vigorous promotion of electric vehicles; it is extremely rare to use bibliometrics to explore the strategies and paths for building urban green transportation networks.

In order to fill the above research gaps, this paper takes the urban green transportation vehicle, “electric vehicle”, as the main research object and systematically reviews and analyzes the relevant literature on electric vehicles in the field of urban green transportation in the WOS and CNKI through the CiteSpace, VOSviewer, and Tableau analysis tools to try to answer the following core questions:

Q1: What is the number of studies regarding electric vehicles in the field of urban green transportation, their publication trend, and the discipline citation path?

Q2: What is the status of cooperation among the main research authors and the research institutions currently involved? Which countries have participated in the studies? What is the geographical distribution of the literature, and what is the mode of cooperation?

Q3: Which topics are the focuses and hot spots in the research of electric vehicles in the field of urban green transportation, and what are the future development and research trends?

Q4: What are the main roles, strategies, and key paths regarding electric vehicles in the construction of an urban green transportation network?

The main research achievements of this paper are as follows: firstly, taking 2650 articles and reviews in the CNKI and 2460 articles and reviews in the WOS as the research objects, the authors use CiteSpace, VOSviewer, and Tableau to analyze the publication trend, author and institution cooperation, keyword co-occurrence and keyword clusters, the evolution trend of burst terms in the timeline, and the content of the literature on electric vehicles in the field of urban green transportation and low-carbon transportation, aiming to review the development process of this field and explore the research hot spots and frontier fields with the help of a visual knowledge map, hoping to achieve a more profound and comprehensive understanding of this field and to provide accurate guidance and support for China to promote electric vehicles, build low-carbon cities, and realize green transportation. In addition, the research in this paper also provides a Chinese solution for building a green transportation network for electric vehicles globally, which not only helps to enhance China’s influence in the international academic community, but also provides practical experience for other countries and regions. In summary, on the one hand, this study enriches the academic research in the field of electric vehicles and green transportation. On the other hand, it provides important theoretical support for the formulation and practice of relevant policies, promoting the progress and development of the relevant disciplines.

The follow-up study in this paper is organized as follows: Section 2 elaborates the data sources and analysis methods; Section 3, Section 4, Section 5 and Section 6 systematically review and deeply analyze the research hot spots, trends, and progress concerning the involved literature; Section 7 and Section 8 comprise the discussion and conclusion portions, analyzing the key role of electric vehicles in building urban green transportation networks.

2. Materials and Methods

2.1. Data Sources and Retrieval Strategies

The data in this paper are mainly obtained from the China National Knowledge Infrastructure (CNKI) and the Web of Science Core Collection (WOS). On 31 August 2024, with (Subject: electric vehicle) AND (Subject: low carbon + low-carbon travel + low-carbon transportation + low-carbon cities + green travel + green transportation + green cities + environmental protection + energy conservation + sustainable development) as search terms, a total of 3526 Chinese studies were retrieved from the CNKI. On this basis, excluding duplicated data, news information, and invalid literature with low correlation, a total of 2650 studies highly relevant to the research theme of this paper were finally screened out.

In WOS, our search string was as follows: (TS = (“electric vehicle*” OR “EV” OR “EVs”)) AND TS = (“low carbon” OR “low-carbon travel” OR “low-carbon transportation” OR “low-carbon cities” OR “green travel” OR “green transportation” OR “green cities” OR “environmental protection” OR “energy conservation” OR “sustainable development”). The search scope is the literature published in all years. The language of the literature is English, and the types are articles and reviews. A total of 2460 articles and reviews highly related to the theme of this study were retrieved from WOS.

2.2. Research Methods and Tools

This paper combines bibliometrics and systematic review as the research methodology. Bibliometrics can effectively mitigate potential research bias that may arise in traditional literature reviews [33]. During the research process, we used CiteSpace (6.2.R3), VOSviewer (1.6.20), and Tableau (2024.1.0) software to conduct a visual analysis of the literature [34,35,36,37,38,39], as these tools complement each other in bibliometric analysis. Specifically, CiteSpace is used for publication trends analysis, dual-map overlay analysis of disciplinary citation paths, author and institutional collaboration analysis, keyword co-occurrence analysis, keyword clustering analysis, and timeline evolution trends, thereby effectively identifying frontier areas and emerging trends regarding the research topics. Meanwhile, VOSviewer is employed to analyze the co-citation patterns in the literature and journals, as well as to study the collaboration relationships among publishing countries or regions. Additionally, we leveraged Tableau to perform a geographic distribution analysis of the international collaborations in the literature and to generate visual maps of the publication volumes and geographic distributions at the country level. The research process of the paper is shown in Figure 1.

3. Publication Trend, Country Cooperation, and Geographical Distribution

3.1. The Number and Trend of Publications

The number of annual publications is an important indicator for analyzing the development process and predicting the future development trends of the research field, which can directly reflect the dynamic changes in the input of the research strength in the field. Via the analysis of the annual publications trend, it can also help researchers to identify the development stage and the future development trend of the field.

The annual number of publications and the publication trend in the research field in the CNKI and WOS are shown in Figure 2 and Figure 3, respectively.

After completing the “Remove Duplicates” step in CiteSpace, statistical analysis of the number of annual publications in the CNKI literature was conducted. In the CNKI, the keyword “electric vehicle” first appeared in 1980. The number of annual publications was less than 10 from 1980 to 1996, and increased year by year in 1997–2007, with approximately 20 examples appearing in 2007. From 2008 to 2011, the number of annual publications in the field of electric vehicle in China increased rapidly from 19 to 230, while in 2012–2014, the number decreased year by year, with only 126 in 2014. Then, from 2015 to 2018, the annual number of publications again increased year by year, with 163 in 2018. Currently, from 2019 to 2024, the number appears to be in a fluctuating state, in which it decreased to 95 in 2020, increased to 102 in 2024 (January to August), and then the annual number of publications in 2019, 2021, 2022, and 2023 stabilized at about 150.

In the WOS, literature in the research field of this paper first appeared in 1996, and the annual publication number was below 10 from 1996 to 2009. In 2010–2018, the annual number of publications increased year by year, with 110 in 2018. Since 2019, the number has increased sharply, reaching 500 in 2023, and in 2024 (January to August), the number was 419.

From the data above, it can be seen that the number of publications in the research field of this paper increased rapidly around 2010, both in the CNKI and WOS, indicating that “electric vehicle” has increasingly become the hot spot for building green, low-carbon cities and developing green, low-carbon transportation. Therefore, this paper chooses 2010 as the starting time, focusing on analyzing literature from 2010 to 2024. This choice is based on the considerations that since 2010, the Chinese government has significantly increased its support for the electric vehicle industry and introduced a series of encouraging policies [40]. Notably, the “Ten Cities, Thousands of Vehicles” program (launched in 2009) entered its large-scale promotion phase in 2010. These initiatives marked the government’s systematic strategic layout, injecting strong momentum into the research and application of electric vehicles [41]. Additionally, from the perspective of data availability and completeness, literature published after 2010 is more abundant and comprehensive in the relevant databases, enabling a more accurate reflection of research trends and developments in this field.

3.2. Dual-Map Overlay Analysis of Disciplinary Citation Paths

In this article, the dual-map overlay function reveals the distribution of main journals in the Web of Science database regarding “research on electric vehicles supporting urban green transportation”, as well as the journals that cite this research, thereby illustrating the flow of knowledge among relevant journals and disciplines in the database. The dual-map overlay consists of two parts: the citing region on the left and the cited region on the right, with curves representing citation connections. The dual-map overlay is shown in Figure 4, and the details of the citation pathways are presented in

Table 1. Domain-level citation patterns in this paper.

No.	Citing Region	Cited Region	Z-Score
1	physics, materials, chemistry	chemistry, materials, physics	6.058974
2	physics, materials, chemistry	environmental, toxicology, nutrition	2.334004
3	veterinary, animal, science	chemistry, materials, physics	2.0093758
4	veterinary, animal, science	environmental, toxicology, nutrition	2.493567
5	veterinary, animal, science	economics, economic, political	1.8910793
6	mathematics, systems, mathematical	chemistry, materials, physics	2.1854453
7	mathematics, systems, mathematical	systems, computing, computer	1.9405988
8	mathematics, systems, mathematical	environmental, toxicology, nutrition	3.233609
9	mathematics, systems, mathematical	economics, economic, political	2.4495487

.

According to Figure 4 and Table 1, research on “electric vehicles supporting urban green transportation” in the WOS database primarily focuses on three disciplinary clusters: “physics, materials, chemistry”, “veterinary, animal, science”, and “mathematics, systems, mathematical”. There are nine outward citation paths, among which the pathway from “physics, materials, chemistry” to “chemistry, materials, physics” has the highest citation count and the highest z-score (z-score = 6.058974). This indicates that research in the field of “electric vehicles supporting urban green transportation” is predominantly concentrated in disciplines such as “physics, materials, chemistry”.

Furthermore, by analyzing the knowledge flow between these disciplinary clusters, we can identify key research areas and potential research gaps. For instance, although the “veterinary, animal, science” cluster has fewer citation pathways compared to those in the “physics, materials, chemistry”, cluster, it may offer unique research perspectives and innovations within specific subfields. Meanwhile, the “mathematics, systems, mathematical” cluster could provide theoretical foundations and methodological support for the optimization and system integration of electric vehicle technologies. By delving into the intersections and collaborations among these disciplines, researchers can gain a better understanding of the multidisciplinary integration trends in the development of electric vehicle technology, thus providing a scientific basis for future research directions and policy formulation in the field of urban green transportation.

3.3. Co-Citation Analysis of References and Journals

In this section, VOSviewer software was used to analyze the co-citation networks of references and journals. Figure 5 displays the co-citation network map of the literature. Using VOSviewer, we analyzed a total of 120,226 cited references and set the minimum citation threshold of 20, resulting in 107 references meeting this threshold for co-citation analysis, as shown in Figure 5a. Subsequently, we plotted the citation density map, where the higher the citation frequency of the literature, the brighter the map appears, as demonstrated in Figure 5b.

The aforementioned literature is mainly divided into three clusters, each represented by a distinct color: red represents Cluster 1, which includes 39 publications that primarily analyze and summarize the barriers and driving factors for the promotion of electric vehicles from the consumer perspective; green represents Cluster 2, which consists of 33 publications that focus on the latest technologies in electric vehicles and their impacts and prospects; blue represents Cluster 3, which also includes 33 publications that primarily investigate the battery technology for electric vehicles and their environmental impacts.

Using VOSviewer software, we filtered out journals with more than 200 citations, totaling 100. Subsequently, we constructed a high-citation journal map and a high-citation density map that each include three clusters. These maps illustrate the research directions and focuses of “electric vehicles” in the fields of “building green and low-carbon cities” and “developing green and low-carbon transportation,” as shown in Figure 6.

As shown in Figure 6a, Applied Energy and the Journal of Cleaner Production have the highest citation counts, reaching 4202 and 4201 citations, respectively. They are followed by journals such as Energy Policy, Energy, and Renewable and Sustainable Energy Reviews. Figure 6b comprises the journal co-citation density visualization map, where the greater the number of citations for a journal, the higher its density. The top 15 journals with the highest citations related to “electric vehicles” in the fields of “building green low-carbon cities” and “developing green low-carbon transportation” are detailed in

Table 2. Citation counts of journals (top 15).

No.	Source	Citations	Total Link Strength
1	Applied Energy	4202	187,096
2	Journal of Cleaner Production	4201	180,334
3	Energy Policy	3852	141,272
4	Energy	3475	165,398
5	Renewable and Sustainable Energy Reviews	3466	186,540
6	Journal of Power Sources	2660	160,651
7	Transportation Research Part D: Transport and Environment	2090	75,219
8	Energies	1932	88,780
9	Sustainability	1592	60,449
10	International Journal of Hydrogen Energy	1409	61,645
11	Transportation Research Part A: Policy and Practice	1325	49,658
12	Energy Conversion and Management	1275	78,757
13	IEEE Transactions on Smart Grid	1213	43,028
14	Environmental Science & Technology	1026	36,463
15	Journal of Energy Storage	1023	67,205

.

3.4. Country Cooperation and Geographical Distribution

In today’s wave of research regarding electric vehicles in urban green transportation, the scientific research strength and contributions of every country can be vividly demonstrated according to the countries cooperation view of the WOS literature. It not only reveals the number of publications of every country in this field, but also reflects their scientific research influence and international cooperation situation. An analysis of national collaborations is conducted using VOSviewer software, and the collaboration map of the countries and regions is shown in Figure 7.

In Figure 7a, the size of the nodes represents the number of publications from each country, with larger nodes indicating a higher volume of publications. According to VOSviewer, 61 countries and regions have published more than five papers, divided into six clusters, indicating collaborative relationships among them. Figure 7b illustrates the cooperation density among countries, showing that countries such as China, the United States, and the United Kingdom display high densities, which indicates a substantial number of publications.

An analysis of the publication volume and geographical distribution of the countries, based on WOS literature, is conducted by using CiteSpace and Tableau software. It is noteworthy that China stands out, with an impressive publication volume of 1100 papers, far surpassing that of other countries. Specifically, the United States follows with 313 publications, showing its strong strength and continuous investment in scientific and technological innovation. The United Kingdom ranks third, with 250 of publications, and its profound academic background and scientific research environment provides strong support for the research of electric vehicles in green transportation. India and Canada rank among the top five, with 170 and 103 publications, respectively, showing their positive efforts and remarkable results in promoting the green transformation of transportation. It is worth noting that there are 5 countries with more than 100 of publications, and the number of countries with more than 50 reaches 15, which shows that the research on electric vehicles in urban green transportation is widely employed and highly valued around the world. The geographic distribution of the number of published papers is shown in Figure 8. The number of publications and citation status by country are shown in

Table 3. The number of publications in and citation status of the WOS literature.

No.	Countries	Count	Centrality	First Published Year	Times Cited (Average per Item)	H-Index	Citation Curve (Figure 9)
1	Peoples R China	1100	0.03	1999	29.08	84	Figure 9a
2	USA	313	0.24	1999	41.45	60	Figure 9b
3	UK	250	0.25	1999	47.49	60	Figure 9c
4	India	170	0.07	1999	18.74	30	Figure 9d
5	Canada	103	0.34	1999	46.92	35	Figure 9e
6	Germany	98	0.43	2006	46.89	35	Figure 9f
7	Italy	89	0.13	1996	31.06	31	Figure 9g
8	Australia	85	0.18	2008	50.72	34	Figure 9h
9	Spain	66	0.22	2013	35.76	26	Figure 9i
10	Saudi Arabia	66	0.1	2014	25.93	18	Figure 9j
11	Japan	66	0.05	1996	33.28	26	Figure 9k
12	South Korea	63	0.04	1997	37.98	25	Figure 9l
13	Denmark	61	0	2011	55.26	30	Figure 9m
14	France	51	0.64	1996	31.47	22	Figure 9n
15	Netherlands	50	0	2008	41.44	27	Figure 9o

.

According to the data provided in Table 3, China accounts for 44.7% of the global literature volume (h-index = 84), but the average citation frequency per paper (29.08) is lower than that of the USA (41.45), the United Kingdom (47.49), Canada (46.92), and Germany (46.89). This indicates that although China has a substantial volume of research output in this field, the citation frequency of these publications is relatively low, reflecting insufficient recognition and influence in the international academic community. The citation curve of the literature from various countries is illustrated in Figure 9. Among the top 50 highly cited studies in China, technical literature constitutes the majority (about 70%), while there are relatively few studies on basic theoretical research, policy research, typical case analysis, and international perspectives, which may also lead to its low citation frequency. In addition, although China has garnered significant achievements in terms of publication volume, its centrality score is only 0.03, far lower than that of countries such as the USA (centrality = 0.24), the UK (centrality = 0.25), Canada (centrality = 0.34), Spain (centrality = 0.22), France (centrality = 0.64), etc. These data reflect that China’s influence and international cooperation in the field of green transportation in regards to electric vehicle cities need to be improved, and efforts are still needed to improve research quality and enhance international cooperation and influence. This is not only a motivation for Chinese researchers, but also an inspiration for future development directions.

4. Analysis of Author Cooperation and Institution Cooperation

4.1. Author Cooperation View Analysis

The author co-occurrence analysis can identify the core authors in a certain field and the cooperation intensity between authors. The number of publications is presented in the form of the size of nodes, the thickness of connecting lines shows the cooperation intensity between authors, and the order of publication time is presented in the form of color shades. The author cooperation views of the CNKI literature and the WOS literature are shown in Figure 10.

In the author cooperation view of the CNKI literature, the number of authors is 702 (N = 702), the number of connecting lines is 220 (E = 220), and the density of the cooperation network is only 0.0009 (density = 0.0009), indicating that there is little cooperation between authors. According to Price’s law, the formula for calculating the number of core authors is $\mathrm{M}\approx 0.749\ast \sqrt{{\mathrm{N}}_{\mathrm{m}\mathrm{a}\mathrm{x}}}$, where M refers to the number of studies, and N_max refers to the number of publications by the author with the most literature published in the corresponding years. If the number of studies published by the author is greater than M, he is the core author. In this paper, the author with the most publications is “Chen, L.Q.”, with a total of 21 papers published, and M is about 3.4. Thus, the minimum number of publications of the core author in this study is 4. The number of publications of the core authors of the CNKI literature is shown in

Table 4. Number of publications of the core authors of the CNKI literature (top 10).

No.	Count	Centrality	First Published Year	Authors
1	21	0	2010	Chen, L.Q.
2	9	0	2004	Wu, Q.T.
3	9	0	1996	Guo, T.J.
4	9	0	2011	Cao, X.A.
5	8	0	2012	Zhen, W.Y.
6	6	0	2007	Feng, F.
7	5	0	2010	Cheng, Z.B.
8	5	0	2011	Wang, P.X.
9	5	0	2015	Du, Y.S.
10	4	0	2012	Liu, Z.W.

.

Through the author cooperation view of the CNKI literature, it can be found that the publication time of “Chen, L.Q.”, the author with the largest number of publications, was focused on the years 2010–2012. He mainly reviewed and analyzed the development and policy support of China’s new energy vehicle industry. He pointed out that the development of the new energy vehicle industry can optimize the consumption structure of transportation energy, reduce urban air pollution, and provide huge economic and social benefits [71,72,73].

Yan, L.G., Ouyang, M.G., Liu, Z.Y., Zhou, F.Q., Kuang, T.Y., Mao, Z.Q., Wu, C.K., and He, Z.X. formed an author group. Their publication time was mainly concentrated on the years 2004–2014, mainly reviewing and analyzing the industrialization process of energy conservation and new energy vehicles in China [74].

Scholars Zhang, Y.M., Yan, Z., and Yu, J.S. have formed a small research team. Their publication time was mainly focused on the years 2022–2023, and they primarily studied the key technologies and applications of a green microgrid for the goals of achieving peak carbon dioxide emissions by 2030 and carbon neutrality by 2060 [75]. The number of publications of the core authors in the WOS literature is shown in

Table 5. Number of publications by the core authors in the WOS Literature (top 10).

No.	Count	Centrality	First Published Year	Authors
1	23	0	2018	Sovacool, Benjamin K.
2	9	0	2021	Wang, Yi
3	9	0	2013	Axsen, Jonn
4	9	0	2020	Strbac, Goran
5	7	0	2020	Li, Yang
6	7	0	2018	Noel, Lance
7	6	0	2018	Kester, Johannes
8	6	0	2019	Hook, Andrew
9	6	0	2023	Sinha, Chittaranjan
10	6	0	2019	Martiskainen, Mari

.

Through the author cooperation view, it can be observed that the author with the largest number of publications is “Sovacool, Benjamin K.”. From 2018 to 2024, he has published more than 20 relevant papers. His main research fields include the analysis of factors influencing people’s preferences for electric vehicles [76,77,78,79], as well as low-carbon transition [80,81,82].

Zhang, N., Zhang, X., Liu, X., Wang, Y., Strbac, G., Zhou, J., Liu, J. and Qiu, D.W. formed an author group, with an important position in the authors’ cooperation network. They mainly studied vehicle-to-grid (V2G), electric vehicle route planning and scheduling, etc. [83,84]. In order to study the interaction mechanism in the system between V2G and energy storage charging piles, a collaborative optimization model considering the complementarity of energy storage and charging in the vehicle was proposed [85].

There are also some small-scale cooperation teams, such as Sun, B., Zhang, Q.J., and Mao, H.J., who formed a small research team. They developed a novel statistical–dynamic energy consumption prediction framework, called the vehicle energy conservation equation (VECE) [86].

4.2. Institution Cooperation View Analysis

The quality and quantity of academic papers are important indicators for evaluating and comparing research institutions, directly affecting their academic influence. The research institution cooperation views of the CNKI and WOS literature are shown in Figure 11.

It can be seen from the research institution cooperation view of the literature in the CNKI that the main research institutions include the China Automotive Technology and Research Center, the Institute of Urban Economics of Tianjin Academy of Social Sciences, the School of Electrical Engineering of Southeast University, Tongji University, etc. The publication numbers for these core research institutions are shown in

Table 6. Number of publications for the core research institutions of the CNKI literature (top 10).

No.	Count	Centrality	First Published Year	Institution
1	19	0	1999	China Automotive Technology and Research Center, Tianjin, China
2	15	0	2019	China Automotive Technology and Research Center Co., Ltd., (CATARC), Tianjin, China
3	10	0	2010	Institute of Urban Economics of Tianjin Academy of Social Sciences, Tianjin, China
4	8	0	2015	Automotive Observer, Beijing, China
5	8	0	2012	School of Electrical Engineering of Southeast University, Nanjing, China
6	8	0	2009	China Electric Power Research Institute (CEPRI), Beijing, China
7	8	0	2011	Tongji University, Shanghai, China
8	8	0	2011	State Grid Energy Research Institute, Beijing, China
9	8	0	2010	China Association of Automobile Manufacturers, Beijing, China
10	8	0	2014	China Automotive Engineering Research Institute Co., Ltd., Chongqing, China

.

According to the research institution cooperation view of the literature in the CNKI, it can be found that the top research institution is the China Automotive Technology and Research Center. The publication time is focused on the years 1999–2019. This institution mainly studied the fiscal and taxation support policies for energy conservation and new energy vehicles, the research and development progress and key deployment of China’s new energy vehicle and battery technology, and the interpretation of the recycling of the traction batteries used in electric vehicle-dismantling specifications [87,88,89].

The second-ranked research institution is the CATARC, with a total of 15 papers published from 2019 to 2024. It has a cooperative relationship with North China Electric Power University, CEPRI, Nanjing Power Supply Company, and other research institutions, forming a cooperative network of research institutions.

The third-ranked research institution is the Institute of Urban Economics of Tianjin Academy of Social Sciences, which focuses on the development and policy of the new energy vehicle industry [71]. The fourth-ranked research institution is the Automotive Observer, which mainly reviews and analyzes the countermeasures and suggestions of industry experts regarding the energy conservation and emission reduction of automobile enterprises, studying the path to achieving carbon peak and carbon neutrality goals for the automobile industry [90,91,92]. The goals of carbon peaking and carbon neutrality have brought new challenges to the automobile industry and provided new opportunities for the development of the new energy vehicle industry.

Through the research institution cooperation view of the literature in the WOS, it can be seen that Tsinghua University, the Chinese Academy of Sciences, the Beijing Institute of Technology, the United States Department of Energy (DOE), Shanghai Jiao Tong University, North China Electric Power University, the University of California System, Imperial College London, Southeast University—China, and the University of Sussex are the top 10 research institutions with the largest number of publications. Among them, there are six Chinese research institutions, two American research institutions, and two British research institutions, as shown in

Table 7. Number of publications for the core research institutions in the WOS literature (top 10).

No.	Count	Centrality	First Published Year	Institution
1	84	0.19	2010	Tsinghua University
2	48	0.09	2004	Chinese Academy of Sciences
3	47	0.13	2013	Beijing Institute of Technology
4	43	0.13	2003	United States Department of Energy (DOE)
5	38	0.06	2008	Shanghai Jiao Tong University
6	36	0.02	2016	North China Electric Power University
7	31	0.07	1999	University of California System
8	30	0.03	2011	Imperial College London
9	28	0.02	2013	Southeast University—China
10	28	0.07	2005	University of Sussex

.

The top research institution is the Tsinghua University of China, which published 84 papers from 2010 to 2024. Especially during 2021–2024, the number of publications increased rapidly, with 20 in 2023. There are 45 domestic and foreign research institutions cooperating with Tsinghua University, and in recent years, their main research direction has been focused on the battery technology of electric vehicles [93,94,95].

The second-ranked research institution is the Chinese Academy of Sciences, which cooperates with 37 institutions, and it published 48 papers in totally. The publication time was mainly focused on the years 2021–2024, with a total of 33 papers. The main research focus was battery recycling for electric vehicles [96,97,98].

The third-ranked research institution is the Beijing Institute of Technology, which published 47 papers in 2013–2024. The publication time was mainly 2021–2024. It cooperates with 23 research institutions, and the main research focuses in the past few years have been energy management and the sharing mode of electric vehicles [99,100,101].

5. Keywords Analysis

5.1. Keyword Co-Occurrence Analysis

In the keyword co-occurrence view, the node size represents the counts of keyword co-occurrence. Keywords with high centrality and counts are the common concern of researchers for a period of time, i.e., the research hot spots. The keyword co-occurrence knowledge mappings for the CNKI and WOS literature are shown in Figure 12.

From the keyword co-occurrence knowledge mapping of the CNKI literature, it can be seen that the count for “electric vehicle” is the highest, and its node is the largest; since “electric vehicle” was used as the subject when retrieving the literature, this keyword is not discussed below.

According to the count of keywords, the top 10 keywords are selected for ranking. Among them, keywords with high counts, such as “energy conservation and emission reduction”, “new energy”, “energy conservation”, “automobile”, “low-carbon economy”, “environmental protection”, and “low carbon” rank high. Keywords such as “energy conservation and emission reduction” (centrality = 0.18), “new energy” (centrality = 0.14), and “low-carbon economy” (centrality = 0.14) exhibit high centrality (centrality ≥ 0.1), which reflects the research focus in this field, to a certain extent, as shown in

Table 8. Keywords with high counts in the CNKI literature (count ≥ 15).

No.	Count	Centrality	First Published Year	Keyword
1	138	0.18	2009	energy conservation and emission reduction
2	98	0.14	2009	new energy
3	87	0.09	1996	energy conservation
4	75	0.12	1993	automobile
5	67	0.14	2009	low-carbon economy
6	55	0.10	1995	environmental protection
7	38	0.04	2010	low carbon
8	33	0.03	2010	energy conservation and environmental protection
9	32	0.07	1999	development
10	32	0.05	2009	smart power grids
11	30	0.02	2021	carbon neutrality
12	28	0.02	2013	energy saving technology
13	25	0.04	2013	carbon emission
14	19	0.04	2010	power battery
15	18	0.03	2009	automobile industry
16	17	0.01	2009	policy
17	16	0.01	2009	low carbon transportation
18	15	0.01	2010	developmental trend

.

The term “energy conservation and emission reduction” refers to the commitment to reduce the energy consumption and pollutant emissions of electric vehicles during their production and use through technological innovation and optimized management. This is closely aligned with China’s “dual carbon” goals and represents a critical direction for promoting the green development of electric vehicles [102]. New energy focuses on the exploration and utilization of cleaner and more sustainable energy sources to power electric vehicles, such as advancements in lithium battery technology and the development of hydrogen fuel cells. This focus aims to explore diversified energy solutions and reduce reliance on traditional fossil fuels [103,104]. The concept of “low-carbon economy” highlights the integration of electric vehicles into the framework of macroeconomic development. By developing the electric vehicle industry, it drives the upstream and downstream industrial chains to transition towards low-carbon development, achieving coordinated economic and environmental development [105,106]. These keywords collectively point to the core research direction of the use of electric vehicles in the field of green transportation, namely how to achieve energy conservation and emission reduction, advocate energy transformation, and promote low-carbon economic development, ultimately achieving the green and sustainable development goals of urban transportation.

It can be seen from the WOS keyword co-occurrence knowledge mapping that “model”, “energy”, “impact”, “system”, “optimization”, “renewable energy”, “performance”, “emissions”, and “sustainable development” are high-frequency keywords. Among them, the keyword, “energy” (centrality = 0.23 > 0.1) reflects the research focus in this field, to a certain extent, as shown in

Table 9. Keywords with high counts in the WOS literature (count ≥ 100).

No.	Count	Centrality	First Published Year	Keyword
1	208	0.07	2005	model
2	179	0.23	2003	energy
3	161	0.05	2013	impact
4	160	0.03	2013	system
5	155	0.01	2013	optimization
6	153	0.03	2013	renewable energy
7	152	0.09	2008	performance
8	140	0.07	1996	emissions
9	139	0.02	2013	sustainable development
10	135	0.02	2015	life cycle assessment
11	130	0.02	2013	management
12	128	0.03	2010	technology
13	110	0.03	2014	policy
14	109	0.05	2014	systems
15	108	0.05	2003	design
16	104	0.02	2017	strategy
17	102	0.01	2013	hybrid
18	102	0.02	2014	China
19	102	0.03	2013	demand

.

5.2. Keyword Timezone Analysis

Through the steps including “pathfinder”, “pruning slice networks” and “pruning the merged network”, the keyword time zone analysis of the literature at this stage was carried out. The keyword time zone view of the literature provides strong support for an understanding of the development progress and hot spot changes regarding electric vehicle use in urban green transportation. Through in-depth analysis of the keywords and hot spots in the time zone view, we can more clearly grasp the development direction and trend of this field. We also can identify the year when the keyword first appeared. The size of the node is the most intuitive reflection of the importance and counts of keywords. The keyword time zone analysis of the literature is shown in Figure 13.

(1)

Keyword time zone analysis of the CNKI literature.

Since the number of relevant studies in the CNKI from 1980 to 1992 is small, the literature of the CNKI used to analyze the keyword time zone in this paper was published from 1993 to 2024. Through the keyword time zone analysis of the CNKI literature, it can be seen that the nodes of keywords like “electric vehicle”, “energy conservation and emission reduction”, “new energy”, “energy conservation”, “automobile”, “low-carbon economy”, and “environment protection” are large, showing that they appear more frequently, which reflects the research hot spots at the stage. Via CiteSpace’s “Show/Hide Citation/Frequency Burst” feature, we can identify keywords such as “energy conservation and emission reduction”, “smart grid”, “low-carbon economy”, “automobile industry”, “policy”, “energy conservation and environmental protection”, “energy saving technology”, “carbon emission”, “energy transition”, “carbon neutrality”, “carbon peak” with a strong citation or burst rate. These keywords not only represent the latest dynamic regarding China’s electric vehicle use in urban green transportation, but also reflect China’s profound thinking and positive actions regarding energy, the environment, and economic development.

Since 2021, keywords such as “carbon neutrality”, “carbon peak”, “green and low-carbon”, “path planning”, “low-carbon optimization”, and “indicator system” have appeared for the first time. It can be seen that Chinese scholars have been focusing on the green low-carbon path planning and the construction of a carbon emission index system for electric vehicles, with the goals of carbon peaking and carbon neutrality. For example, Zhou, C., et al. (2024) constructed a scientific and comprehensive regional carbon emission index system for electric vehicles, covering four dimensions, i.e., regional development, low-carbon transportation, vehicle operation, and power production. They measured 12 key indexes of carbon emissions from electric vehicles and selected six representative provinces in China for case verification [107]. The regional carbon emission index of electric vehicles can effectively quantify the comprehensive carbon emission level of electric vehicles and identify the advantages and disadvantages of the low-carbon development of the electric vehicle industry in different regions, as well as provide a reference for seeking the optimization path to achieve the low-carbon transition of electric vehicles at the regional level.

(2)

Keyword time zone analysis of the WOS literature.

It can be seen from the keyword time zone view of the WOS literature that the keyword “electric vehicles” first appeared in 1996, and keywords like “emissions” and “air pollution” appeared for the first time this year as well, indicating that the scholars were beginning to pay attention to greenhouse gas emissions and air pollution. Since 2021, the global academic community has set off a wave for electric vehicle research in regards to urban green transportation. A series of keywords such as “lithium-ion battery”, “decision making”, “carbon neutrality”, “battery recycling”, “techno-economic analysis”, and “emission reduction” appeared frequently in the WOS literature. This trend not only highlights the close attention paid by international scholars regarding environmental protection and the sustainable development of electric vehicles, but also heralds profound changes in energy structure and technological innovation for the global automobile industry.

In addition, through the keywords time zone view of the WOS literature, it can also be seen that “valuable metals” in 2021 and “lithium-ion batteries” in 2022 were the keywords showing strong citation or burst rates. As the core power source of electric vehicles, the lithium-ion battery is related to the performance, safety and cost of electric vehicles, so its importance is self-evident [108]. How to improve the energy density, prolong the cycle life, and reduce the manufacturing cost of lithium-ion batteries have become hot topics in the current research [109]. With the rapid development of electric vehicles, the demand for lithium-ion batteries has increased dramatically, which has also produced a series of problems, such as resource shortages and environmental pollution. Therefore, how to efficiently and sustainably produce, use, and recycle lithium-ion batteries is also one of the current research hot spots [110,111].

5.3. Keyword Cluster Analysis

The keywords in the literature of the CNKI and WOS are clustered by CiteSpace. The keyword cluster analysis views and peak views of the literature in the CNKI and WOS are shown in Figure 14, Figure 15 and Figure 16, respectively.

In the CNKI keyword cluster view, N = 586, E = 982, density = 0.0057, modularity Q = 0.6281 > 0.3, and mean silhouette = 0.8706 > 0.5. In the WOS keyword cluster view, N = 785, E = 2772, density = 0.009, modularity Q = 0.5829 > 0.3, and mean silhouette = 0.7769 > 0.5. It can be seen that the keyword cluster effects of the literature in both the CNKI and WOS are all superior, and the credibility is high.

According to the keyword cluster peak view, it can be seen that the time when each cluster starts, continues, and ends, as well as the heights of the peaks, indicate the activity of the clusters. Through the CNKI literature keyword cluster peak view, it can be seen that the keyword #1, “energy conservation and emission reduction” cluster started around 2005, and the peak gradually rose in 2009–2012, indicating that the studies related to the “energy conservation and emission reduction” cluster increased at that time. The peak of the keyword #2, “carbon neutrality” cluster has risen rapidly since 2021, indicating that the studies related to the cluster have increased rapidly from then on. In recent years, the Chinese government has attached great importance to climate change and has included the “twin goals”—carbon peaking and carbon neutrality—into the country’s overall development strategy. In September 2020, President Xi Jinping proposed China’s carbon peak and carbon neutrality goals at the 75th session of the United Nations General Assembly. In October 2021, the Chinese government issued the document titled, “Working Guidance for Carbon Dioxide Peaking and Carbon Neutrality in Full and Faithful Implementation of the New Development Philosophy”. With the promotion of national policies, carbon peaking and carbon neutrality have gradually become hot topics in scientific research.

Through observing the WOS keyword cluster peak view, it can be seen that the keyword #0, “transportation system” cluster started in 2008–2009, developed rapidly after 2014, and reached its peak in 2018–2020, indicating that research on this cluster was active in this period. The research on the keyword #1, “lithium-ion batteries” cluster started in 2010–2011. And since 2020, the number of studies relevant to this cluster has increased greatly and the peak has also risen rapidly, indicating that this cluster has become a hot spot.

Via keywords cluster analysis, it can be seen that the CNKI keyword cluster includes: “energy conservation and emission reduction”, “carbon neutrality”, “low-carbon economy”, “new energy”, “energy conservation”, “environmental protection”, “charging station”, “green low carbon”, “green transportation”, and 13 other clusters. The number of WOS keyword clusters is 11, including “transportation system”, “lithium-ion batteries”, “carbon emission”, “systematic literature review”, etc.

Through the keywords cluster analysis of the literature in the CNKI and WOS, it can be divided into three main hot research directions.

(1)

Research on the infrastructure of electric vehicles.

This research field includes four CNKI keyword clusters and three WOS keyword clusters.

CNKI cluster: #0 electric vehicle, #4 automobile, #8 charging station, and #10 automobile industry. Labels related to the infrastructure research of electric vehicles also included “environmental conservation vehicle”, “charging facilities”, “power batteries”, etc.

WOS cluster: #1 lithium-ion batteries, #6 hybrid electric vehicle, and #10 charging station.

Xue, B., et al. (2021) studied the sustainable development of small vehicle power batteries for carbon neutrality [112]. It has become an urgent task to promote the sustainable development of human society, realizing the efficient and environmentally friendly recycling and reuse of waste lithium-ion batteries (LIBs) [113]. He, H., Wei, J., and Wang, Z. (2024) analyzed the problems existing regarding the efficiency and degree of environmental protection for the charging systems of electric vehicles in China, putting forward an optimization strategy for electric vehicle charging systems [114]. Chen, H., Luo, X., and Zhang, J. (2024) predicted the demand for a charging infrastructure for electric vehicles and proposed suggestions for formulating the development plan for the charging infrastructure of electric vehicles [115].

(2)

Research on electric vehicles to aid in energy conservation and emission reduction, low carbon output, and environmental protection.

This research field contains three CNKI keyword clusters and two WOS keyword clusters.

CNKI cluster: #1 energy conservation and emission reduction, #6 energy conservation, and #7 environmental protection.

WOS cluster: #2 carbon emission and #8 priority pollutant list.

Electric vehicles offer the advantages of environmental protection, energy conservation, and emission reduction, which can reduce energy consumption and emissions and play a positive role in building a green and low-carbon society. Energy conservation and environmental protection have become the main trends in automobile technology development, and studying new energy and energy conservation technology for automobiles is an effective way to solve energy shortages and reduce the environmental pollution caused by automobiles [116]. Wu, X. (2022) studied the energy conservation planning of electric vehicles based on big data technology [117]. Gong, H., et al. (2023) introduced the development status of China’s new energy electric vehicles, analyzed the energy conservation and emission reduction effects of new energy electric vehicles with the help of energy consumption calculation methods and carbon emission calculation methods, and proposed the development path for new energy electric vehicles in China [118]. Yu, B., et al. (2024) proposed a carbon emission calculation method and a carbon emission flow calculation model for electric vehicles, which can track the carbon flow during the charging and discharging of electric vehicles in real time, accurately quantifying the carbon emission reductions [119].

(3)

Research on electric vehicles and their contributions to the green, low carbon, and sustainable development of urban transportation.

This research field contains six CNKI keyword clusters and two WOS keyword clusters.

CNKI cluster: #2 carbon neutrality, #3 low-carbon economy, #5 new energy resources, #9 control strategy, #11 green and low-carbon, and #12 green transport.

WOS cluster: #0 transportation system and #7 sustainable transport system development.

Cities are the basic unit of human production and living, as well as the basic unit for measuring carbon emissions and environmental pollution. They are also an important part of carbon emission reduction and sustainable development [120]. In order to protect the ecological environment, all localities should integrate the concept of ecological progress and green, circular, and low-carbon development into urban transportation development planning and vigorously build a green transportation system [121]. Xuan, Y. (2024) designed a method to optimize the allocation of electric vehicle charging stations, considering low-carbon transportation, and quantitatively analyzed the impact of charging station planning schemes on transportation carbon emissions by establishing a low-carbon transportation indicator system that comprehensively took four factors, i.e., carbon emissions, transportation energy structure, transportation electric energy cleanliness, and charging station usage rate, into account [122]. Ding, L. (2023) analyzed the situation of domestic and foreign policies related to automobile carbon emissions, studied the carbon emissions of the whole life cycle of the automobile, and put forward suggestions for the low-carbon development of the automobile industry [123].

6. Analysis of the Evolution Trend in Timeline Form

The “Burst Terms” analysis feature of CiteSpace can analyze the latest research trends and the frontier of “electric vehicles”. The burst terms of this study are shown in Figure 17.

Through the analysis of the burst terms and timeline, we can see that keywords such as “energy conservation and emission reduction”, “energy transition”, “energy conservation technology”, “carbon neutrality”, “carbon peak”, and “carbon emissions”, in the CNKI literature, and keywords like “emissions”, “power system”, “renewable energy”, “storage”, “fuel consumption”, “recovery”, “lithium-ion batteries”, in literature of the WOS, have comprised the research hot spots and frontiers in recent years. Research using the keyword “emissions” in WOS literature extends through the whole cycle (1996–2024), with an especially a large number studies appeared in 2009–2016, and it became the research hot spot at that time. From 2021 to 2024, scholars have focused on keywords such as “recovery”, “lithium-ion batteries”, and “valuable metals”. It can be seen that the recycling of automobile batteries and the effective reuse of valuable metals in batteries have become the research hot spots over the past three years.

CiteSpace is used to draw the timeline views of for the CNKI literature and the WOS literature, as shown in Figure 18 and Figure 19, respectively.

From the timeline view, we can analyze the changes of the research hot spots for electric vehicles in urban green transportation, as well as the hot spots regarding development trends in the timeline. The location of each node represents the time that the keyword first appeared, and the more occurrences, the larger the node becomes.

7. Discussion

7.1. Publication Trends and Country Cooperation in the Literature

Through literature analysis, it can be observed that the research focus on electric vehicles in the field of green low-carbon transportation has gradually increased since 2010. This trend reflects a broad global consensus regarding the key role of electric vehicles in alleviating traffic pollution and solving the energy crisis. Especially since 2019, the annual publication volume of WOS literature in this research field has shown a significant growth trend. By 2023, the number of publications had reached 500, and in 2024, it had reached 419 in the period from January to August alone, a phenomenon that has been attributed to the growing global focus on sustainable transportation, the active promotion of government policies in various countries, and the rapid advancements in electric vehicle technology. In the analysis of publication volume at the national level, China is far ahead of other countries, with 1100 WOS publications. This remarkable achievement is closely related to the high attention paid by the Chinese government to the electric vehicle industry, the strong policy support, and the rapid growth of market demand. Despite China’s leading position in terms of the number of studies focusing on electric vehicles, the centrality score is far lower than that of France, Canada, the UK, the USA, and other countries, which means that China’s relevant studies need to be further strengthened in terms of international academic influence and international cooperation.

7.2. Author Cooperation and Institutional Cooperation

In terms of author cooperation, it can be seen that in the CNKI, Chen Liuqin, the author with the highest number of publications, published 21 papers, showing his importance in the field. His studies mainly focus on the development and policy support of the new energy vehicle industry, emphasizing the key role of new energy vehicles in optimizing the transportation energy consumption structure and reducing urban air pollution. In the WOS, the author group led by Sovacool, Benjamin K., whose studies involve the preference for electric vehicles and low-carbon transition, reflects the global attention on electric vehicle research, from multiple perspectives. Through the cooperation network of these core authors, it can be seen that international research cooperation is gradually increasing.

As for institutional cooperation, institutions such as the China Automotive Technology and Research Center occupy the leading positions in the ranking of publication volume in the CNKI, indicating their importance in the field. They have provided important theoretical support and policy recommendations for the development of new energy vehicles in China. In the WOS, Tsinghua University performs particularly well, ranking first in terms of the number of publications, showing its leading position in regards to electric vehicle research. Its cooperation with 45 research institutions, at home and abroad, further demonstrate its extensive influence in the international academic community. Tsinghua University’s research on electric vehicle battery technology is one of the major current technical bottlenecks regarding new energy vehicles, showing its foresight and practicality. In addition, institutions such as the Chinese Academy of Sciences and the Beijing Institute of Technology have also played an important role in the field of electric vehicles, focusing on battery recycling and energy management, respectively. These studies not only provide an important theoretical basis for the sustainable development of new energy vehicles, but also provide a scientific reference for the formulation of relevant policies.

In general, through the analysis of the author cooperation view and the institutional cooperation view, it can be seen that the cooperation among Chinese scholars and institutions needs to be further strengthened. It is suggested that relevant research institutions and scholars should actively seek interdisciplinary and inter-agency cooperation and promote international exchanges and collaboration, which will help to further enhance the global influence of electric vehicle research.

7.3. The Evolution of Keyword Research via Timeline

By analyzing the literature, the research and development of China’s electric vehicles in the field of urban green transportation and low-carbon transportation can be clearly divided into three stages. This phased division not only reflects the evolution of technology and policy, but also reveals the changes in China’s strategic direction and academic focus on electric vehicles.

(1)

1993–2008: initial exploration stage.

At this stage, the electric vehicle industry had just started in China, and hot keywords such as “environmental protection”, “environmentally friendly vehicles”, “development”, “environmental protection”, “automobile”, and “alternative fuels” appeared frequently. These keywords reflect the initial attention to and exploration of electric vehicles by scholars at that time. The government’s supportive policies provided a good environment for the development of electric vehicles.

Research Focus: The research in this period mainly focuses on the basic concept, the technical route of electric vehicles, and a preliminary evaluation of market demand. At this stage, scholars began to pay attention to how to promote the development of green cars through policy support and regulation formulation.

Policy Support: The active involvement of the government provided the impetus for the budding of the electric vehicle industry. Although the technology and market were still in the initial stage, this period laid the foundation for subsequent development.

(2)

2009–2020: rapid development period.

This stage comprises the rapid development period of China’s electric vehicle research and industrialization. Hot keywords such as “low-carbon economy”, “smart grid”, “policy”, “automobile industry”, “energy conservation and environmental protection”, “low-carbon transportation”, and “charging pile” appeared frequently. The “Ten Cities, Thousands of Vehicles” initiative, launched in 2009, marked the official start of the industrialization of new energy vehicles [124].

Market Environment: With the development of the economy and the improvement in living standards, the public’s attention on energy issues and environmental pollution increased. With the advantages of low-carbon emissions, environmental protection, and high efficiency, electric vehicles became an important low-carbon transportation carrier [125]. The research at this stage focused not only on technological progress, but also on changes in policy, market, and social needs.

Industrialization Process: The electric vehicle industry achieved rapid development with the support of national policies and scientific research strength, and the relevant industrial chains were gradually improving, laying the foundation for subsequent technological innovation and market expansion.

(3)

2021–2024: high-speed development and “twin goals”.

At this stage, hot keywords such as “carbon neutrality”, “carbon peak”, “carbon emissions”, “recovery”, and “lithium-ion batteries” show the close integration of China’s electric vehicle research with current policies. The “twin goals” proposed in 2020 point out the direction for the development of the electric vehicle industry.

Strategic Objectives: The goals of carbon peaking and carbon neutrality make electric vehicles an important path to achieve green and low-carbon transportation [126]. Relevant research has begun to pay attention to the carbon emissions of the product life cycle, emphasizing the importance of electric vehicles in the future green development of transportation [127].

Technological innovation: At this stage, China’s electric vehicle industry has made remarkable progress in regards to technological innovation. The application of new charging technology, efficient driving systems, and automatic driving technology is being rapidly promoted, enhancing the international competitiveness of Chinese brand electric vehicles.

Market Expansion: Electric vehicles not only occupy an important position in the domestic market, but are also gradually moving towards the global market, showing China’s technical strength and market potential in the field.

Through the stage-by-stage analysis of China’s electric vehicle research and development in the field of “urban green transportation and low-carbon transportation”, it can be seen that the development of the electric vehicle industry is closely related to national policies, market demand, and technological innovation. From the initial exploration stage, to the rapid development period, and then to the current high-speed development stage, China’s electric vehicle industry has formed a relatively complete ecosystem. In the future, with the deepening of the “twin goals”, the electric vehicle industry will continue to usher in new opportunities and challenges in regards to technological innovation and market expansion. The academic community should continue to pay attention to the research in this field and provide a scientific basis for policy formulation and industrial development.

7.4. Research Hot Spots and Frontier Trends

Through the analysis of burst terms and timeline evolution, the research hot spots and frontier trends for electric vehicles and related fields in the WOS and CNKI literature can be clearly recognized.

In the CNKI literature, the frequency and burst rate of keywords such as “energy conservation and emission reduction”, “energy transformation”, “carbon neutrality”, “carbon peak”, and “carbon emissions” reveal the importance of this field in recent years. These keywords not only reflect China’s strategic goals in addressing climate change and promoting sustainable development, but also show the in-depth study of relevant technologies and policies in academia.

Energy Conservation and Emission Reduction: The frequent occurrence of this keyword indicates that researchers are actively exploring ways to reduce energy consumption and greenhouse gas emissions through technological innovation and policy measures. This point is highly consistent with China’s “twin goals”, reflecting the country’s emphasis on sustainable development.

Energy Transformation: With the rapid development of renewable energy, energy transformation has become the global focus. Researchers have begun to explore how to effectively promote the transformation of traditional energy to clean energy in order to achieve the dual benefits of economic development and environmental protection.

Carbon Neutrality and Carbon Peak: The emergence of these keywords marks China’s active participation in global climate governance. Scholars focus on how to achieve the peak of carbon emissions and the ultimate carbon neutrality. Their research directions include policy design, the technology path, and economic incentives.

In the WOS literature, keywords such as “emissions”, “power system”, “renewable energy”, “storage”, “fuel consumption”, “recovery” and “lithium-ion batteries” reveal research hot spots in the international academic community in regards to electric vehicles and related fields.

Emissions: This keyword runs through the entire research cycle from 1996 to 2024. Especially from 2009 to 2016, the number of relevant studies surged, showing that scholars paid close attention to greenhouse gas emissions during this period. This trend reflects the increasing global attention on climate change and the in-depth discussion of the potential of electric vehicles in regards to emission reduction.

Renewable Energy and Power System: The emergence of these keywords reflects the close relationship between electric vehicles and renewable energy systems. Researchers explore how to combine electric vehicles with smart grids and renewable energy to achieve more efficient energy use and a lower environmental impact.

Recovery and Lithium-Ion Batteries: From 2021 to 2024, scholarly research including keywords such as “recovery”, “lithium-ion batteries”, and “valuable metals” has increased significantly. This shows that with the popularity of electric vehicles, the recycling of batteries and the effective reuse of their internal valuable metals have become the research hot spots. The life cycle management of batteries, the innovation of recycling technology, and the sustainable utilization of resources are currently the focus of the academic world and the industrial community.

In summary, by analyzing the keywords and the evolution of timelines in the WOS and CNKI literature, it can be observed that the research hot spots in regards to electric vehicles and related fields are changing continually. Chinese scholarly research under the “twin goals” focuses on energy conservation, emission reduction, and carbon emission management, while the international academic community pays more attention to the technological frontiers, such as battery recycling and resource utilization. These studies not only provide theoretical support for the development of electric vehicles, but also offer a practical basis for policy formulation and technological innovation, promoting the sustainable development of the global automobile industry.

7.5. The Impact Analysis of Electric Vehicles on the Urban Transportation Network in China

This article utilizes CiteSpace and VOSviewer software to analyze the challenges faced by electric vehicles in supporting the construction of a green and low-carbon transportation network in Chinese cities.

(1)

Policy Dimension: The Contradiction between Policy Incentives and Implementation Gaps.

Current Status and Impact: Policy is the core driving force behind the development of the electric vehicle industry [128]. In recent years, the Chinese government has introduced a series of policies, such as “The New Energy Vehicle Industry Development Plan (2021–2035)” [129] and “The Implementation Opinions on Further Enhancing the Service Guarantee Capacity of Electric Vehicle Charging Infrastructure” [130], aimed at accelerating the popularization of electric vehicles and the transformation of urban transportation networks through policy guidance and support. Guan, X., et al. (2025) conducted an in-depth analysis of the carbon emission reduction effects of new energy vehicles in China on 27 provinces (excluding Taiwan, Xinjiang, Tibet, Ningxia, Qinghai, Hong Kong, and Macau) using time-series data between 2016 and 2022 [131]. The research findings indicate that the carbon emission reduction effects of new energy vehicles showed an overall upward trend, with a significant acceleration since 2021. This shift may be closely related to “The New Energy Vehicle Industry Development Plan (2021–2035)” and associated policies released by the Chinese government in November 2020, which provided substantial support for the development of new energy vehicles and carbon emission reduction efforts.

Existing Dilemmas: Despite substantial policy support, some issues regarding the actual implementation process remain. For example, there exist a lack of coordination and consistency among policies, discrepancies between local and national policies, and low levels of policy alignment among different local governments, resulting in the incomplete realization of policy effects [126]. Additionally, the long-term nature and stability of the current policies need to be further strengthened to avoid market fluctuations and investment risks for enterprises [132]. At the same time, the implementation of policies lacks effective supervision and evaluation mechanisms [133], which may lead to resource waste and inefficiency.

(2)

Technological Dimension: The Disconnect Between Technological Advancement and Practical Application.

Current Status and Impact: Technological advancement serves as the cornerstone of the development of the electric vehicle industry [134]. In recent years, significant breakthroughs have been made in electric vehicle technology, particularly concerning battery technology, charging technology, and intelligent management systems [135]. For instance, improvements in battery energy density and charging efficiency have led to substantial enhancements in the driving range and user convenience of electric vehicles [136]. Furthermore, the optimization of intelligent traffic management systems and route planning algorithms has provided technological support for the efficient operation of urban transportation networks [137,138].

Existing Dilemmas: Despite significant technological advancements, there are still some bottlenecks. For example, further breakthroughs in battery technology are limited by material science and manufacturing processes [139,140], while the lack of unified technical standards for the charging infrastructure has resulted in charging compatibility issues [141]. Additionally, the intelligent and connected technologies of electric vehicles still require refinement to meet the complex demands of urban transportation networks [142]. Specifically, the current mainstream lithium-ion batteries face limitations in regards to materials science for improving energy density. For example, positive and negative electrode materials should exhibit good reversibility, a high ion diffusion rate and electronic conductivity, a long cycle life, good ecological compatibility, and low cost [143]. In terms of manufacturing processes, consistency and stability issues during the production process affect battery quality and performance [144,145]. In terms of charging infrastructure, the lack of unified technical standards has led to differences in charging interfaces and protocols for different brands and models of electric vehicles, seriously affecting charging compatibility and causing great inconvenience to users [146,147].

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Infrastructure Dimension: The Contradiction of Challenges in the Construction and Popularization of Charging Networks.

Current Status and Impact: The improvement of infrastructure is a crucial support for the promotion of electric vehicles [148]. In recent years, China has accelerated the construction of charging stations, battery-swapping stations, and other infrastructure, forming an initial charging network that covers urban and intercity transportation [149]. For example, the construction of charging infrastructure and urban smart traffic management systems has not only improved traffic efficiency but also promoted the green transformation of urban transportation networks [150]. The continuous development of charging infrastructure provides a solid guarantee for the popularization of electric vehicles, thereby enhancing their market acceptance and user experience [151].

Existing Dilemmas: Although progress has been made in infrastructure construction, there are still some issues. Vinicius, B., et al. (2025) argue that in areas with low usage of electric vehicles, investors are reluctant to build charging stations due to insufficient charging demand. In contrast, in areas where electric vehicles are widely used, the speed for constructing charging infrastructure cannot keep up with the growth rate of vehicles, resulting in insufficient charging facilities in some areas, especially in remote areas and urban–rural areas [152]. For example, the distribution of charging stations is uneven, with insufficient charging facilities in certain areas, especially in remote regions and urban–rural fringe zones, where electric vehicle users often face inconveniences in charging [153,154]. Additionally, the maintenance and management of charging infrastructure also need to be further strengthened to improve the utilization rate and reliability of the facilities [155].

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Social Dimension: Challenges of Enhanced Awareness of Green Travel and the Lag in Usage Habits.

Current Status and Impact: The promotion of electric vehicles has had a profound effect on social lifestyles and travel habits [156]. With the widespread adoption of electric vehicles, public awareness and acceptance of green travel have gradually increased, leading more people to choose electric vehicles as their daily means of transportation [157,158]. Furthermore, the promotion of electric vehicles has also facilitated the development of shared mobility and smart travel, further optimizing urban transportation networks [159,160].

Existing Dilemmas: Despite the growing social acceptance, several obstacles persist. For instance, some consumers harbor concerns about the range capabilities and charging convenience of electric vehicles, which negatively impacts their purchasing decisions [161]. Additionally, the usage habits and cultural norms surrounding electric vehicles remain underdeveloped, creating an urgent need for enhanced public education and promotional efforts to facilitate societal acceptance and behavioral adaptation [162,163].

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Economic Dimension: Dual Challenges of Market Competitiveness and Industry Chain Improvement.

Current Status and Impact: The promotion of electric vehicles has exerted a profound impact on urban economic structures and industrial chains [16]. The continuously increasing sophistication of the electric vehicle industry chain has driven rapid development across related industries, including battery manufacturing, charging infrastructure production, and intelligent transportation management systems [164]. Additionally, the widespread adoption of electric vehicles has also catalyzed the green economy and sustainable development strategies of cities, injecting new momentum into the ecological transformation and technological upgrading of urban mobility systems [165].

Existing Dilemmas: Although electric vehicles significantly contribute to economic growth, they still face several challenges. For instance, the production and usage costs of electric vehicles remain relatively high, which somewhat limits their market competitiveness [166]. From the perspective of ownership costs, the purchase cost of an electric vehicle is generally higher than that of a traditionally fueled vehicle, mainly due to the high cost of batteries, which accounts for a large proportion of the total vehicle cost [167,168]. In terms of the economic efficiency of charging stations, the current charging station construction costs are relatively high [169], including site leasing, equipment procurement, installation, and commissioning costs. Additionally, the utilization rates of some charging stations are relatively low, particularly in remote areas and emerging regions, resulting in long investment payback periods [170]. Moreover, the overall improvement of the electric vehicle industry chain still requires further enhancement to boost overall efficiency and competitiveness, allowing it to better meet market demands [171].

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Environmental Dimension: The Dual Challenge of Insufficient Life Cycle Assessment and the Lack of Ecological Benefit Monitoring.

Status and Impact: The promotion of electric vehicles has generated a positive impact on environmental sustainability [172]. The widespread adoption of electric vehicles has reduced the carbon emissions from traditional fuel-powered vehicles, contributing to the achievement of carbon peak and carbon neutrality goals [173]. Furthermore, the promotion of electric vehicles has also encouraged the use of clean energy, further optimizing the energy structure in urban areas [174].

Existing Dilemmas: Despite the significant environmental benefits, several issues persist. For example, the lifecycle emissions assessment of electric vehicles has not been fully implemented, leading to a lack of systematic analysis of their environmental impacts at the production, usage, and disposal stages [175]. Although the positive effects of electric vehicles on urban ecological environments are recognized [176], there is an absence of systematic ecological benefit evaluation and research on their impact on residents’ health and quality of life, which constrain public awareness and undermine the effectiveness of promotion policies [177,178,179].

8. The Path of Electric Vehicles to Build an Urban Green Transportation Network

8.1. Exploring China’s Solutions for Building a Green Transportation Network

Based on scientometric methodologies, this paper systematically deconstructs the knowledge foundations, evolutionary trajectories, and multidimensional bottlenecks in the electric vehicle-driven development of green and low-carbon urban transportation networks in China and finally innovatively constructs a six-dimensional analytical framework of “policy-driven–technological innovation–infrastructure support–social response–economic reconstruction–ecological collaboration”. After in-depth research and comprehensive analysis of the relevant literature, at home and abroad, the authors propose the Chinese plan for how to build an urban green transportation network, specifically regarding the application of electric vehicles. The program will be discussed from several dimensions, such as policy support, technological innovation, infrastructure construction, social acceptance, economic benefits, and environmental protection, as shown in Figure 20.

8.1.1. Policy Support

Incentive Policy: Wang, S., et al. (2024) [180] selected panel data from 20 provinces and cities from 2010 to 2020 to examine the implementation effects of incentive policies on the promotion and application of new energy vehicles in China from multiple perspectives. The results indicate that incentive policies can effectively promote the adoption of new energy vehicles, but the impact of local subsidy policies varies across different regions. It is suggested that governments, at all levels, should issue a series of preferential policies, including providing car purchase subsidies, exemption from purchase tax, reduction in parking fees for electric vehicle buyers, etc. to reduce the cost of purchasing and using electric vehicles and stimulate market demand. Financial institutions are encouraged to provide low-interest loans, i.e., green funds to guide social capital to expand participation in the industrial development of electric vehicles.

Standards and Regulations: Standards and regulations related to electric vehicles should be established to ensure product quality and safety and facilitate the healthy development of the market, e.g., establishing technical standards and safety regulations to ensure the compliance of electric vehicles in the market.

Long-term Planning: A medium and long-term green transportation development plan should be formulated, clarifying the status and role of electric vehicles in the urban green transportation network.

8.1.2. Technological Innovation

Battery Technology Breakthroughs: In order to solve the bottleneck faced by current battery technology, government departments at all levels should increase research and development (R&D) investment, focusing on breakthroughs in key core technologies for electric vehicles and power batteries. Advancements in these technologies will help improve the energy density, charging speed, and lifespan of batteries, thereby reducing the overall cost of electric vehicles and lowering the threshold for users. Specifically, government agencies and research teams should ramp up R&D efforts in regards to new battery materials, actively exploring novel battery systems such as solid-state batteries, lithium–sulfur batteries, and lithium–silicon batteries. For instance, Shchurov, N.I., et al. (2021) point out that silicon-based anodes exhibit significant application potential due to their high theoretical capacity (approximately ten times that of graphite) [181]. However, to fully leverage the advantages of silicon materials, several critical issues need to be addressed, including enhancing the electrical conductivity of silicon, managing the volume expansion during charging and discharging, and overcoming the difficulties involved in the large-scale production of silicon nanowire materials. Once these issues are resolved, silicon nanowires hold broad application prospects in the field of power batteries.

Intelligent Driving and Internet of Vehicles: It is recommended that government at all levels and relevant enterprises increase their support to promote the rapid development of autonomous driving technology and Internet of vehicles technology to further enhance the safety and convenience of electric vehicles, which can improve the users’ travel experience. For example, the improvement of autonomous driving technology will enable vehicles to respond more intelligently to various complex road conditions and reduce human errors in operation, thereby enhancing overall driving safety. And the development of vehicle networking technology will enable vehicles to communicate efficiently with other vehicles and transportation infrastructure. This information sharing can effectively reduce traffic congestion and improve road use efficiency.

8.1.3. Infrastructure Construction

Charging Network Layout: It is suggested that government at all levels should further improve the construction and planning of charging infrastructure and facilitate the efficient interaction between electric vehicles and smart grids. For example, charging infrastructure should be built in parking lots, bus stations, and expressway service areas, especially in key areas such as residential areas, commercial areas, and office areas so as to ensure that electric vehicle users can charge their vehicles conveniently, anytime and anywhere.

Intelligent Charging System: Using the Internet of things technology and big data analysis, the intelligent charging management system should be constructed to realize the optimal allocation and scheduling of charging resources, improve the charging efficiency, and reduce the user wait time. Moreover, we should encourage the use of renewable energy sources such as solar energy and wind energy in charging facilities to enhance the green attributes of electric vehicles. Referring to the research ideas of Wang, K., et al. (2025) [182], we consider coordinating with the integrated power distribution system in the construction of intelligent charging systems. This includes optimizing the layout and operation strategy of charging facilities to improve the resilience and stability of the entire energy system. For example, in the face of emergencies or power supply fluctuations, the coordinated management of intelligent charging systems ensures the normal charging of electric vehicles, while minimizing the impact on the overall energy system.

8.1.4. Social Acceptance

Public Awareness: Government at all levels should strengthen their education and publicity activities to enhance citizens’ awareness and participation in green travel, forming form a green transportation and green travel culture with the participation of the whole population.

User Experience: There should be a focus on the optimization of the user experience, improving charging convenience, endurance, and vehicle performance to improve user satisfaction. The convenience of the charging facilities directly affects the public’s acceptance of electric vehicles, and a good user experience can further enhance users’ recognition of and trust in electric vehicles. Enterprises should be encouraged to participate in the promotion and application of electric vehicles, and enterprises’ innovation and practice regarding green travel should be supported, striving to form a joint force comprising government, enterprises, and the public.

8.1.5. Economic Benefits

Cost–Benefit Analysis: When evaluating the cost of using electric vehicles, it is recommended to comprehensively compare electric vehicles with traditional fuel vehicles, which includes many aspects such as purchase costs, maintenance costs, and fuel costs. Through detailed calculation and comparison, we can understand the advantages and disadvantages of electric vehicles in terms of economy so as to provide a strong basis for consumers and enterprises to make decisions.

Market Potential: Electric vehicles exhibit huge potential in different markets, but each market is different. It is suggested that the government and enterprises should deeply analyze the characteristics of each market, identify the target user groups, and understand needs and preferences of each one. On this basis, the corresponding market strategy is formulated to maximize the market share and brand influence of electric vehicles.

8.1.6. Environmental Protection

Emission Assessment: In order to fully understand the impact of electric vehicles on the environment during their life cycle, it is recommended that the government and related companies regularly conduct detailed emission assessments. This assessment process covers all stages of electric vehicles, from production, to use, to scrap, aiming to deeply analyze their comprehensive impact on the environment. Through this assessment, the public can better understand the impact of electric vehicles on the environment at all stages of their life cycle, thus providing a scientific reference for improving and optimizing the production and use of electric vehicles.

Ecological Benefits: Zhao, X., et al. (2024) [183] used the spatial econometric model to investigate the impact of promoting new energy vehicles on carbon emissions. The research findings indicate that a 1% increase in new energy vehicle sales in a city would reduce local carbon emissions by 0.096%. The positive impact of electric vehicles on the urban ecological environment is obvious, especially in terms of improving air quality, reducing noise pollution, and mitigating the urban heat island effect. In order to better understand and quantify these effects, it is recommended that the government and related enterprises regularly conduct a systematic analysis and evaluation of the urban ecological benefits. First of all, regular monitoring of air quality changes, especially in areas with a high popularization rate for electric vehicles, can help us understand the actual effect of electric vehicles on reducing harmful gas emissions. This not only helps to develop more effective environmental policies but also provides a scientific basis for the public to enhance their trust and support for electric vehicles. Secondly, the assessment of noise pollution is equally important. By comparing the noise levels of electric vehicles and traditional fuel vehicles in different areas of the city, relevant departments can recognize the contribution of electric vehicles to reducing urban noise so as to promote more urban planning and traffic management measures to further improve the living quality of residents. In addition, research on the urban heat island effect should also be included in the assessment. By analyzing the impact of the use of electric vehicles on urban temperature changes, the government can better formulate strategies to cope with climate change and promote sustainable urban development.

Social Benefits: It is recommended that the government and relevant enterprises regularly analyze and evaluate the positive impact of electric vehicle promotion on residents’ health, quality of life, and socioeconomic development. First, the impact of electric vehicle promotion on residents’ health can be quantified by monitoring air quality, residents’ health data, and the incidence of related diseases. Second, electric vehicles produce less noise and can improve urban residents’ living quality. Thus, it is recommended to obtain an understanding of the impact of electric vehicles on people’s daily lives through resident surveys and satisfaction assessments. Third, the development of the electric vehicle industry can create employment opportunities and promote the innovation and progress of related technologies. Therefore, governments and enterprises can regularly analyze the economic contribution of the electric vehicle industry chain, including manufacturing, sales, charging facilities construction, and maintenance and evaluate its role in promoting the local economy.

8.2. Analysis of Implementation Difficulty and Potential Impact in Cities of Different Sizes

Large cities: Taking Beijing as an example, as a megacity, it benefits from strong financial resources in terms of policy support. However, the complexity of urban planning and the difficulty of interdepartmental coordination poses significant challenges. Nevertheless, in large cities, the ownership of electric vehicles is generally high, and the demand is very robust. For example, the number of new energy vehicles in Beijing has exceeded 1 million [184]. Once the charging infrastructure is completed, the high utilization rate of these facilities will have a significant impact on reducing carbon emissions and alleviating traffic congestion.

Medium-sized cities: Taking Shijiazhuang as an example, policy support is relatively flexible, but financial resources are limited. This results in subsidies and R&D investments that cannot compared to those of large cities. In order to promote development, Shijiazhuang City plans to optimize and improve the layout of charging piles before 2025 and to initiate the Bulinke New Energy Charging Pile and Energy Storage Project in the Economic and Technological Development Zone in order to consolidate the pilot achievements of the comprehensive electrification of vehicles in the public sector [185].

Small cities: Taking Tang County in Hebei Province as an example, policy formulation is simple, but fiscal revenue is low, restricting the sustainability and strength of policy support. Meanwhile, due to the small population and industrial scale, there is insufficient support for the electric vehicle industry, making it difficult to promote. To address this issue, Tang County plans to accelerate the construction of charging infrastructure in 2025 and implement consumption policies to comprehensively promote the trade-in of old cars for new ones [186].

8.3. Differentiated Implementation Pathways for Green Transportation Networks

Large, medium-sized, and small cities each possess unique advantages and face distinct challenges regarding the development of the electric vehicle industry. Cities should formulate corresponding policies and strategies based on their specific characteristics to promote the healthy and sustainable growth of the electric vehicle sector.

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Implementation path for large cities.

Policy Support: The government should enhance interdepartmental coordination, establish long-term and stable policies, and integrate resources from various stakeholders.

Technological Innovation: Governments and R&D institutions should increase investment in the research and development of core technologies related to electric vehicles, particularly in regards to battery technology and autonomous driving. Additionally, enterprises and research organizations should be encouraged to strengthen international collaboration to attract top global talents and advanced technologies, thereby promoting the high-end development of the industry.

Infrastructure Construction: The government should accelerate the construction of high-speed and efficient charging networks and promote intelligent charging and battery swapping technologies to enhance the user experience.

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Implementation path for medium-sized cities.

Policy Support: Local governments should actively seek funding from higher authorities and formulate targeted policies for electric vehicles that align with local industrial characteristics. For example, Shijiazhuang City can leverage its strengths in the steel industry to formulate supporting policies.

Technological Innovation: Local governments should actively collaborate with research institutions in large cities to facilitate technology transfer, introduce advanced technologies, and cultivate local talent.

Infrastructure Construction: Local governments should rationally lay out the charging networks based on urban development plans. Priority should be given to constructing charging facilities in core areas, public service zones, and transportation hubs of cities to meet the growing demand for electric vehicle charging.

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Implementation Path for Small Cities.

Policy Support: The government should actively seek support and funding from the national and provincial levels and guide local enterprises to participate in supporting services related to the electric vehicle industry.

Technological Innovation: The government should encourage local enterprises to strengthen technical exchanges and cooperation with developed regions and actively send professional personnel to study advanced technologies in developed regions.

Infrastructure Construction: The government should rationally plan the layout of charging facilities based on actual needs. It is recommended to adopt a gradual development strategy, focusing on distributed and small-scale charging facilities to reduce construction costs and improve resource utilization efficiency.

9. Conclusions, Research Limitations, and Research Prospects

9.1. Conclusions

This paper uses analysis tools, specifically, CiteSpace, to review and perform a visual analysis of 2650 studies in the China National Knowledge Infrastructure (CNKI) database and 2460 studies in the Web of Science Core Collection (WOS) database. The results show the following: (1) In the CNKI, the number of publications regarding electric vehicles in urban green transportation increased rapidly from 2008 to 2011, and the annual number of publications over the past three years fluctuated around 150. In the WOS, the number of annual publications in this research field has shown a rapid growth trend. Since 2019, it has increased sharply, reaching 500 in 2023. (2) In terms of the literature in the CNKI, the number of cooperative studies between authors and the number of research teams are small, and the degree of cooperation between authors is low, with a dispersed research state. The literature in the WOS also displays this problem. (3) In recent years, the research hot spots in this field in the CNKI have mainly focused on “energy conservation and environmental protection”, “energy conservation and emission reduction”, “carbon neutrality”, “carbon peak”, “carbon emissions”, and other fields. In the WOS, the research hot spots include “recovery”, “lithium-ion batteries”, “valuable metals”, etc. (4) With the rapid development of science and technology and the general improvement in environmental awareness, people are paying more attention to low-carbon and green transportation. (5) This paper explores the impact of electric vehicles on urban traffic networks in China and systematically analyzes their innovative role. We have innovatively constructed a six-dimensional analytical framework of “policy-driven–technological innovation–infrastructure support–social response–economic reconstruction–ecological collaboration” and proposed strategies and pathways for electric vehicles to facilitate the construction of green transportation networks in cities.

The development of green transportation is an important part of building a low-carbon city. As a representative of green transportation, electric vehicles have great development prospects and advantages. The government, enterprises, and all social circles should work together to promote the transformation of urban transportation into a low-carbon and environmentally friendly entity. Therefore, the government should continue to increase the support for the electric vehicle industry and accelerate the popularization of electric vehicles in cities through policy guidance and technological innovation, jointly building a greener, healthier, and more harmonious low-carbon city.

9.2. Research Limitations

Although this study employs scientometric methods to systematically analyze the application of electric vehicles in urban green transportation, it still displays certain limitations. The data, sourced primarily from the CNKI and Web of Science Core Collection databases, may lead to incompleteness. Industry reports, internal corporate research, and other materials which might contain crucial information on market dynamics, technological innovation practices, and other aspects of electric vehicles, were not included in the analysis. The absence of such data could affect the comprehensive analysis of certain research directions. For instance, when analyzing the development of the electric vehicle industry chain, the lack of industry report data might hinder an accurate understanding of the actual progress in some niche areas. Therefore, the findings of this study may not fully encompass all aspects of the field. Future research should consider expanding data collection channels to obtain more comprehensive and accurate conclusions.

9.3. Prospects for Future Research

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Research on vehicle intelligence.

Under the major trend of green transportation, the development of intelligent electric vehicles will become a new trend. With the rapid development of mobile communication, Internet of things, and other technologies, the vehicle information system is advancing to be more intelligent and Internet-based. In the future, the intelligent vehicle network technology will be further improved, and it is believed that the deep interaction between the vehicle system and the cloud will create a better intelligent green transportation experience [187].

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Research on lightweight materials for vehicles.

In order to cope with increasingly stringent emission regulations, the lightweight design of automobiles has become one of the future trends. The use of advanced materials such as carbon fiber and aluminum alloy can significantly reduce vehicle weight and improve energy efficiency so as to increase the mileage of electric vehicles [188].

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Research on autonomous driving technology.

Autonomous driving technology is the hot spot in the research of electric vehicle technology. Through the integration of advanced sensors, artificial intelligence algorithms, and big data analysis technology, the autonomous navigation and decision making of vehicles will be realized. In the future, with the continuous optimization of algorithms and breakthroughs in sensor technology, autonomous vehicles will be able to more accurately identify and perceive the surrounding environment, thereby achieving a higher level of autonomous driving [189].

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Research on power battery technology innovation.

Researchers are working to develop higher energy density, longer lifespan, and safer battery technologies to meet the growing demand for electric vehicle endurance [190]. In addition, the charging technology is also continually advancing, aiming to shorten the charging time and improve the charging efficiency to improve the user experience.

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Research on urban transportation planning.

Urban transportation planning is very important for promoting the development of green transportation. Future research should focus on how to rationally plan green transportation networks through intelligent transportation systems to improve urban transportation efficiency and reduce traffic congestion and carbon emissions [191]. At the same time, it is also necessary to consider how intelligent transportation systems can be combined with urban planning, land use, and environmental protection policies to achieve a more comprehensive green transportation network.

These research hot spots jointly promote the continuous progress of electric vehicle technology and provide solid technical support for future urban green transportation.