Previous Issue

Table of Contents

Batteries, Volume 5, Issue 2 (June 2019)

  • Issues are regarded as officially published after their release is announced to the table of contents alert mailing list.
  • You may sign up for e-mail alerts to receive table of contents of newly released issues.
  • PDF is the official format for papers published in both, html and pdf forms. To view the papers in pdf format, click on the "PDF Full-text" link, and use the free Adobe Readerexternal link to open them.
Cover Story (view full-size image) While the concept of circular economy has recently gained major attention, it is necessary to [...] Read more.
View options order results:
result details:
Displaying articles 1-13
Export citation of selected articles as:
Open AccessArticle
Model-Based Investigation of Porosity Profiles in Graphite Anodes Regarding Sudden-Death and Second-Life of Lithium Ion Cells
Received: 5 April 2019 / Revised: 16 May 2019 / Accepted: 21 May 2019 / Published: 1 June 2019
Viewed by 495 | PDF Full-text (1036 KB) | HTML Full-text | XML Full-text
Abstract
The second-life concept helps to reduce the cost for electric vehicles by adding monetary value to disused automotive batteries. However, the sudden-death effect, a change in ageing behaviour limits the total lifetime and might reduce the second-life timespan. In this paper, we utilize [...] Read more.
The second-life concept helps to reduce the cost for electric vehicles by adding monetary value to disused automotive batteries. However, the sudden-death effect, a change in ageing behaviour limits the total lifetime and might reduce the second-life timespan. In this paper, we utilize a common pseudo two-dimensional (P2D) cell model to investigate the influence of different porosity profiles in the graphite electrode on the battery’s ageing. Ageing is modeled by two irreversible side reactions at the anode, the formation of solid electrolyte interface (SEI) and lithium plating. We use parameters of a high-energy cell with thick electrodes. A constant initial anode porosity as a reference is compared with two optimized porosity profiles. Simulation results show that by using a layered anode, a two-stage porosity profile with higher porosity at the separator side, the cycle count until sudden-death and especially the cycles for second-life applications can both almost be doubled. Full article
Figures

Figure 1

Open AccessArticle
Life Cycle Analysis of Lithium-Ion Batteries for Automotive Applications
Received: 28 March 2019 / Revised: 30 April 2019 / Accepted: 8 May 2019 / Published: 1 June 2019
Viewed by 446 | PDF Full-text (2060 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
In light of the increasing penetration of electric vehicles (EVs) in the global vehicle market, understanding the environmental impacts of lithium-ion batteries (LIBs) that characterize the EVs is key to sustainable EV deployment. This study analyzes the cradle-to-gate total energy use, greenhouse gas [...] Read more.
In light of the increasing penetration of electric vehicles (EVs) in the global vehicle market, understanding the environmental impacts of lithium-ion batteries (LIBs) that characterize the EVs is key to sustainable EV deployment. This study analyzes the cradle-to-gate total energy use, greenhouse gas emissions, SOx, NOx, PM10 emissions, and water consumption associated with current industrial production of lithium nickel manganese cobalt oxide (NMC) batteries, with the battery life cycle analysis (LCA) module in the Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation (GREET) model, which was recently updated with primary data collected from large-scale commercial battery material producers and automotive LIB manufacturers. The results show that active cathode material, aluminum, and energy use for cell production are the major contributors to the energy and environmental impacts of NMC batteries. However, this study also notes that the impacts could change significantly, depending on where in the world the battery is produced, and where the materials are sourced. In an effort to harmonize existing LCAs of automotive LIBs and guide future research, this study also lays out differences in life cycle inventories (LCIs) for key battery materials among existing LIB LCA studies, and identifies knowledge gaps. Full article
(This article belongs to the Special Issue Sustainable Lithium Ion Batteries: From Production to Recycling)
Figures

Figure 1

Open AccessArticle
Estimation Accuracy and Computational Cost Analysis of Artificial Neural Networks for State of Charge Estimation in Lithium Batteries
Received: 1 April 2019 / Revised: 2 May 2019 / Accepted: 7 May 2019 / Published: 1 June 2019
Viewed by 468 | PDF Full-text (5092 KB) | HTML Full-text | XML Full-text
Abstract
This paper presents a tradeoff analysis in terms of accuracy and computational cost between different architectures of artificial neural networks for the State of Charge (SOC) estimation of lithium batteries in hybrid and electric vehicles. The considered layouts are partly selected from the [...] Read more.
This paper presents a tradeoff analysis in terms of accuracy and computational cost between different architectures of artificial neural networks for the State of Charge (SOC) estimation of lithium batteries in hybrid and electric vehicles. The considered layouts are partly selected from the literature on SOC estimation, and partly are novel proposals that have been demonstrated to be effective in executing estimation tasks in other engineering fields. One of the architectures, the Nonlinear Autoregressive Neural Network with Exogenous Input (NARX), is presented with an unconventional layout that exploits a preliminary routine, which allows setting of the feedback initial value to avoid estimation divergence. The presented solutions are compared in terms of estimation accuracy, duration of the training process, robustness to the noise in the current measurement, and to the inaccuracy on the initial estimation. Moreover, the algorithms are implemented on an electronic control unit in serial communication with a computer, which emulates a real vehicle, so as to compare their computational costs. The proposed unconventional NARX architecture outperforms the other solutions. The battery pack that is used to design and test the networks is a 20 kW pack for a mild hybrid electric vehicle, whilst the adopted training, validation and test datasets are obtained from the driving cycles of a real car and from standard profiles. Full article
Figures

Figure 1

Open AccessArticle
Synthesis and Electrochemical Performance of Ni-Doped VO2(B) as a Cathode Material for Lithium Ion Batteries
Received: 16 March 2019 / Revised: 14 May 2019 / Accepted: 20 May 2019 / Published: 1 June 2019
Viewed by 324 | PDF Full-text (1751 KB) | HTML Full-text | XML Full-text
Abstract
Ni-doped VO2(B) samples (NixVO2(B)) were fabricated by a facile one-step hydrothermal method. When evaluated as a cathode material for lithium ion batteries (LIBs), these Ni-doped VO2(B) exhibited improved lithium storage performance as compared to the [...] Read more.
Ni-doped VO2(B) samples (NixVO2(B)) were fabricated by a facile one-step hydrothermal method. When evaluated as a cathode material for lithium ion batteries (LIBs), these Ni-doped VO2(B) exhibited improved lithium storage performance as compared to the pure VO2(B). In particular, when the doping amount is 3%, NixVO2(B) showed the highest lithium storage capacity, best cycling stability, smallest electrochemical reaction resistance, and largest lithium diffusion coefficient. For example, after 100 cycles at a current density of 32.4 mA/g, NixVO2(B) delivered a high specific discharge capacity of 163.0 mAh/g, much higher than that of the pure VO2(B) sample (95.5 mAh/g). Therefore, Ni doping is an effective strategy for enhancing the lithium storage performance of VO2(B). Full article
(This article belongs to the Special Issue Cathode Materials for Lithium-Ion Batteries)
Figures

Graphical abstract

Open AccessArticle
A Post-Mortem Study of Stacked 16 Ah Graphite//LiFePO4 Pouch Cells Cycled at 5 °C
Received: 22 March 2019 / Revised: 19 April 2019 / Accepted: 24 April 2019 / Published: 7 May 2019
Viewed by 615 | PDF Full-text (5033 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Herein, the post-mortem study on 16 Ah graphite//LiFePO4 pouch cells is reported. Aiming to understand their failure mechanism, taking place when cycling at low temperature, the analysis of the cell components taken from different portions of the stacks and from different positions [...] Read more.
Herein, the post-mortem study on 16 Ah graphite//LiFePO4 pouch cells is reported. Aiming to understand their failure mechanism, taking place when cycling at low temperature, the analysis of the cell components taken from different portions of the stacks and from different positions in the electrodes, is performed by scanning electron microscopy (SEM), X-ray diffraction (XRD) and X-ray photoemission spectroscopy (XPS). Also, the recovered electrodes are used to reassemble half-cells for further cycle tests. The combination of the several techniques detects an inhomogeneous ageing of the electrodes along the stack and from the center to the edge of the electrode, most probably due to differences in the pressure experienced by the electrodes. Interestingly, XPS reveals that more electrolyte decomposition took place at the edge of the electrodes and at the outer part of the cell stack independently of the ageing conditions. Finally, the use of high cycling currents buffers the low temperature detrimental effects, resulting in longer cycle life and less inhomogeneities. Full article
(This article belongs to the Special Issue Batteries and Supercapacitors Aging)
Figures

Figure 1

Open AccessArticle
Recovery of Cobalt from Spent Lithium-Ion Mobile Phone Batteries Using Liquid–Liquid Extraction
Received: 25 March 2019 / Revised: 13 April 2019 / Accepted: 18 April 2019 / Published: 6 May 2019
Viewed by 616 | PDF Full-text (4998 KB) | HTML Full-text | XML Full-text
Abstract
The aim of this paper was to propose and test a continuous cobalt recovery process from waste mobile phone batteries. The procedure started with dismantling, crushing, and classifying the materials. A study on leaching with sulfuric acid and hydrogen peroxide was carried out [...] Read more.
The aim of this paper was to propose and test a continuous cobalt recovery process from waste mobile phone batteries. The procedure started with dismantling, crushing, and classifying the materials. A study on leaching with sulfuric acid and hydrogen peroxide was carried out with subsequent selective separation of cobalt by means of liquid–liquid extraction. The best extraction conditions were determined based on a sequence of experiments that consisted of selecting the best extractant for cobalt, then assessing the impact of extractant concentration, pH, and contact time on the extraction yield. With these conditions, an extraction isotherm was obtained and correlated with a mathematical model to define the number of extraction stages for a countercurrent process using the McCabe–Thiele method. Then, a similar study was done for stripping conditions and, as a last step, cobalt electroplating was performed. The proposed process offers a solution for the treatment of these batteries, avoiding potential problems of contamination and risk for living beings, as well as offering an opportunity to recover valuable metal. Full article
(This article belongs to the Special Issue Circular Economy of Batteries Production and Recycling)
Figures

Graphical abstract

Open AccessArticle
Optimized Process Parameters for a Reproducible Distribution of Relaxation Times Analysis of Electrochemical Systems
Received: 15 February 2019 / Revised: 4 April 2019 / Accepted: 11 April 2019 / Published: 5 May 2019
Viewed by 618 | PDF Full-text (1170 KB) | HTML Full-text | XML Full-text
Abstract
The distribution of relaxation times (DRT) analysis offers a model-free approach for a detailed investigation of electrochemical impedance spectra. Typically, the calculation of the distribution function is an ill-posed problem requiring regularization methods which are strongly parameter-dependent. Before statements on measurement data can [...] Read more.
The distribution of relaxation times (DRT) analysis offers a model-free approach for a detailed investigation of electrochemical impedance spectra. Typically, the calculation of the distribution function is an ill-posed problem requiring regularization methods which are strongly parameter-dependent. Before statements on measurement data can be made, a process parameter study is crucial for analyzing the impact of the individual parameters on the distribution function. The optimal regularization parameter is determined together with the number of discrete time constants. Furthermore, the regularization term is investigated with respect to its mathematical background. It is revealed that the algorithm and its handling of constraints and the optimization function significantly determine the result of the DRT calculation. With optimized parameters, detailed information on the investigated system can be obtained. As an example of a complex impedance spectrum, a commercial Nickel–Manganese–Cobalt–Oxide (NMC) lithium-ion pouch cell is investigated. The DRT allows the investigation of the SOC dependency of the charge transfer reactions, solid electrolyte interphase (SEI) and the solid state diffusion of both anode and cathode. For the quantification of the single polarization contributions, a peak analysis algorithm based on Gaussian distribution curves is presented and applied. Full article
Figures

Figure 1

Open AccessArticle
Synthetic vs. Real Driving Cycles: A Comparison of Electric Vehicle Battery Degradation
Received: 4 April 2019 / Revised: 17 April 2019 / Accepted: 19 April 2019 / Published: 1 May 2019
Cited by 1 | Viewed by 645 | PDF Full-text (4500 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Automobile dependency and the inexorable proliferation of electric vehicles (EVs) compels accurate predictions of cycle life across multiple usage conditions and for multiple lithium-ion battery systems. Synthetic driving cycles have been essential in accumulating data on EV battery lifetimes. However, since battery deterioration [...] Read more.
Automobile dependency and the inexorable proliferation of electric vehicles (EVs) compels accurate predictions of cycle life across multiple usage conditions and for multiple lithium-ion battery systems. Synthetic driving cycles have been essential in accumulating data on EV battery lifetimes. However, since battery deterioration is path-dependent, the representability of synthetic cycles must be questioned. Hence, this work compared three different synthetic driving cycles to real driving data in terms of mimicking actual EV battery degradation. It was found that the average current and charge capacity during discharge were important parameters in determining the appropriate synthetic profile, and traffic conditions have a significant impact on cell lifetimes. In addition, a stage of accelerated capacity fade was observed and shown to be induced by an increased loss of lithium inventory (LLI) resulting from irreversible Li plating. New metrics, the ratio of the loss of active material at the negative electrode (LAMNE) to the LLI and the plating threshold, were proposed as possible predictors for a stage of accelerated degradation. The results presented here demonstrated tracking properties, such as capacity loss and resistance increase, were insufficient in predicting cell lifetimes, supporting the adoption of metrics based on the analysis of degradation modes. Full article
(This article belongs to the Special Issue Batteries and Supercapacitors Aging)
Figures

Figure 1

Open AccessArticle
On the Use of Statistical Entropy Analysis as Assessment Parameter for the Comparison of Lithium-Ion Battery Recycling Processes
Received: 31 January 2019 / Revised: 2 April 2019 / Accepted: 3 April 2019 / Published: 23 April 2019
Viewed by 700 | PDF Full-text (3926 KB) | HTML Full-text | XML Full-text
Abstract
The principle of the circular economy is to reintroduce end-of-life materials back into the economic cycle. While reintroduction processes, for example, recycling or refurbishing, undoubtedly support this objective, they inevitably present material losses or generation of undesired by-products. Balancing losses and recoveries into [...] Read more.
The principle of the circular economy is to reintroduce end-of-life materials back into the economic cycle. While reintroduction processes, for example, recycling or refurbishing, undoubtedly support this objective, they inevitably present material losses or generation of undesired by-products. Balancing losses and recoveries into a single and logical assessment has now become a major concern. The present work broadens the use of relative statistical entropy and material flow analysis to assess the recycling processes of two lithium-ion batteries previously published in the literature. Process simulation software, that is, HSC Sim®, was employed to evaluate with a high level of accuracy the performance of such recycling processes. Hereby, this methodology introduces an entropic association between the quality of final recoveries and the pre-processing stages, that is, shredding, grinding, and separation, by a parameter based on information theory. The results demonstrate that the pre-processing stages have a significant impact on the entropy value obtained at the final stages, reflecting the losses of materials into waste and side streams. In this manner, it is demonstrated how a pre-processing system capable of separating a wider number of components is advantageous, even when the final quality of refined products in two different processes is comparable. Additionally, it is possible to observe where the process becomes redundant, that is, where processing of material does not result in a significant concentration in order to take corrective actions on the process. The present work demonstrates how material flow analysis combined with statistical entropy can be used as a parameter upon which the performance of multiple recycling processes can be objectively compared from a material-centric perspective. Full article
(This article belongs to the Special Issue Circular Economy of Batteries Production and Recycling)
Figures

Figure 1

Open AccessArticle
Considerations when Modelling EV Battery Circularity Systems
Received: 1 February 2019 / Revised: 8 April 2019 / Accepted: 8 April 2019 / Published: 15 April 2019
Viewed by 750 | PDF Full-text (1703 KB) | HTML Full-text | XML Full-text
Abstract
The electric vehicle market is expected to grow substantially in the coming years, which puts new requirements on the end-of-life phase and on the recycling systems. To a larger extent, the environmental footprint from these vehicles is related to raw material extraction and [...] Read more.
The electric vehicle market is expected to grow substantially in the coming years, which puts new requirements on the end-of-life phase and on the recycling systems. To a larger extent, the environmental footprint from these vehicles is related to raw material extraction and production, and, consequently, a material- and energy-efficient 3R system (reuse, remanufacturing, recycling) is urgently needed. The ability to understand and model the design and development of such a system therefore becomes important. This study contributes to this by identifying factors that affect 3R system design and performance, relating these factors to the various actors and processes of the system and categorising them according to time from implementation to impact. The above is achieved by applying a PEST analysis (political, economic, social and technological factors), differentiating between political, economic, social and technological factors. Data were gathered from literature, by interviews and by a number of workshops in the automotive industry and the 3R system and observations at meetings, etc. The study confirms some previous results on how vehicle battery 3R systems work and adds knowledge about the influencing factors, especially the timeframes and dynamics of the system, necessary for modelling the system and the influencing factors. For practitioners, the results indicate how to use appropriate models and which factors are most relevant to them. Full article
(This article belongs to the Special Issue Circular Economy of Batteries Production and Recycling)
Figures

Graphical abstract

Open AccessArticle
Effect of Mixed Li+/Na+-ion Electrolyte on Electrochemical Performance of Na4Fe3(PO4)2P2O7 in Hybrid Batteries
Received: 14 March 2019 / Revised: 2 April 2019 / Accepted: 4 April 2019 / Published: 11 April 2019
Viewed by 713 | PDF Full-text (1377 KB) | HTML Full-text | XML Full-text
Abstract
The mixed sodium-iron ortho-pyrophosphate Na4Fe3(PO4)2P2O7 (NFPP) is a promising Na-containing cathode material with the highest operating voltage among sodium framework structured materials. It operates both in Na and Li electrochemical cells. When [...] Read more.
The mixed sodium-iron ortho-pyrophosphate Na4Fe3(PO4)2P2O7 (NFPP) is a promising Na-containing cathode material with the highest operating voltage among sodium framework structured materials. It operates both in Na and Li electrochemical cells. When cycled in a hybrid Li/Na cell, a competitive co-intercalation of the Li+ and Na+ ions occurs at the cathode side. The present study shows that this process can be tuned by changing the concentration of the Na+ ions in the mixed Li+/Na+-ion electrolyte and current density. It is shown that if the Na concentration in the electrolyte increases, the specific capacity of NFPP also increases and its high-rate capability is significantly improved. Full article
(This article belongs to the Special Issue Advanced Hybrid-Ion Batteries)
Figures

Figure 1

Open AccessArticle
Segmented Printed Circuit Board Electrode for Locally-Resolved Current Density Measurements in All-Vanadium Redox Flow Batteries
Received: 6 March 2019 / Revised: 6 April 2019 / Accepted: 8 April 2019 / Published: 11 April 2019
Viewed by 845 | PDF Full-text (2957 KB) | HTML Full-text | XML Full-text
Abstract
One of the most important parameters for the design of redox flow batteries is a uniform distribution of the electrolyte solution over the complete electrode area. The performance of redox flow batteries is usually investigated by general measurements of the cell in systematic [...] Read more.
One of the most important parameters for the design of redox flow batteries is a uniform distribution of the electrolyte solution over the complete electrode area. The performance of redox flow batteries is usually investigated by general measurements of the cell in systematic experimental studies such as galvanostatic charge-discharge cycling. Local inhomogeneity within the electrode cannot be locally-resolved. In this study a printed circuit board (PCB) with a segmented current collector was integrated into a 40 cm2 all-vanadium redox flow battery to analyze the locally-resolved current density distribution of the graphite felt electrode. Current density distribution during charging and discharging of the redox flow battery indicated different limiting influences. The local current density in redox flow batteries mainly depends on the transport of the electrolyte solution. Due to this correlation, the electrolyte flow in the porous electrode can be visualized. A PCB electrode can easily be integrated into the flow battery and can be scaled to nearly any size of the electrode area. The carbon coating of the PCB enables direct contact to the corrosive electrolyte, whereby the sensitivity of the measurement method is increased compared to state-of-the-art methods. Full article
Figures

Figure 1

Open AccessArticle
Innovative Incremental Capacity Analysis Implementation for C/LiFePO4 Cell State-of-Health Estimation in Electrical Vehicles
Received: 27 January 2019 / Revised: 11 March 2019 / Accepted: 15 March 2019 / Published: 1 April 2019
Viewed by 823 | PDF Full-text (3771 KB) | HTML Full-text | XML Full-text
Abstract
This paper presents a fully embedded state of health (SoH) estimator for widely used C/LiFePO4 batteries. The SoH estimation study was intended for applications in electric vehicles (EV). C/LiFePO4 cells were aged using pure electric vehicle cycles and were monitored with [...] Read more.
This paper presents a fully embedded state of health (SoH) estimator for widely used C/LiFePO4 batteries. The SoH estimation study was intended for applications in electric vehicles (EV). C/LiFePO4 cells were aged using pure electric vehicle cycles and were monitored with an automotive battery management system (BMS). An online capacity estimator based on incremental capacity analysis (ICA) is developed. The proposed estimator is robust to depth of discharge (DoD), charging current and temperature variations to satisfy real vehicle requirements. Finally, the SoH estimator tuned on C/LiFePO4 cells from one manufacturer was tested on C/LiFePO4 cells from another LFP (lithium iron phosphate) manufacturer. Full article
(This article belongs to the Special Issue Batteries and Supercapacitors Aging)
Figures

Figure 1

Batteries EISSN 2313-0105 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top