Batteries

24 pages, 555 KiB

Open AccessArticle

Comparison of Kalman Filter and H-Infinity Filter for Battery State of Charge Estimation with a Detailed Validation Method

by Waleri Milde and Laurin Kerle

Batteries 2025, 11(4), 161; https://doi.org/10.3390/batteries11040161 (registering DOI) - 18 Apr 2025

Abstract

Accurate and reliable estimation of the state of charge (SOC) of lithium-ion batteries is essential for the performance and safety of battery management systems (BMS) in applications such as electric vehicles and energy storage systems. However, there is a lack of comprehensive comparative [...] Read more.

Accurate and reliable estimation of the state of charge (SOC) of lithium-ion batteries is essential for the performance and safety of battery management systems (BMS) in applications such as electric vehicles and energy storage systems. However, there is a lack of comprehensive comparative studies evaluating different SOC estimation methods under standardized conditions. In this paper, we address this gap by providing a comprehensive, objective comparison of various Kalman and H-Infinity filter variants for battery SOC estimation, utilizing a detailed validation method based on well-defined criteria. The main contributions of this work are: (1) Implementation of multiple filter variants using a consistent equivalent circuit battery model; (2) Development of a standardized validation method for objective performance evaluation; (3) Detailed mathematical formulations enhancing reproducibility; (4) Evaluation of computational efficiency on a digital signal processor (DSP) to provide practical insights for real-time applications. Our findings reveal that while neither filter type is universally superior, the Extended Kalman Filter (EKF) and H-Infinity Filter (HIF) offer a solid balance between estimation accuracy and computational load, making them reliable choices for general applications. This work advances the understanding of SOC estimation methods and aids practitioners in balancing accuracy and computational efficiency for real-world applications. Full article

(This article belongs to the Collection Advances in Battery Energy Storage and Applications)

19 pages, 3739 KiB

Open AccessArticle

Online Core Temperature Estimation for Lithium-Ion Batteries via an Aging-Integrated ECM-1D Coupled Model-Based Algorithm

by Yiqi Jia, Lorenzo Brancato, Marco Giglio and Francesco Cadini

Batteries 2025, 11(4), 160; https://doi.org/10.3390/batteries11040160 - 18 Apr 2025

Abstract

Thermal management is pivotal for ensuring the safe and efficient operation of LIBs under dynamic conditions. Accurate core temperature monitoring remains a key BTMS challenge for predicting thermal distributions and mitigating TR risks. This study proposes a real-time core temperature estimation framework integrating [...] Read more.

Thermal management is pivotal for ensuring the safe and efficient operation of LIBs under dynamic conditions. Accurate core temperature monitoring remains a key BTMS challenge for predicting thermal distributions and mitigating TR risks. This study proposes a real-time core temperature estimation framework integrating joint EKF with an electro-thermal-aging model (ECM-1D). Using only surface temperature and voltage measurements, it simultaneously estimates core temperature, SOC, and capacity with bidirectional electro-thermal coupling. The hybrid approach pre-calibrates temperature/SOC/SOH-dependent parameters offline while updating capacity online. Validation under extreme conditions (high-rate cycling, aging, and ISCs) demonstrates 60% lower core temperature RMSE during high-rate cycling, a maximum estimation error below 0.9 K, and 58.9% reduction in SOC estimation error under aging conditions versus existing methods. The framework reliably tracks core temperature trends despite parasitic heat and signal noise, enabling earlier critical temperature warnings. This provides a foundation for TR prevention, advancing battery safety for EV and grid storage applications. Future extensions could integrate physical aging mechanisms and enhance fault detection capabilities. Full article

(This article belongs to the Special Issue Thermal Management in Lithium-Ion Batteries: Latest Advances and Prospects)

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20 pages, 15674 KiB

Open AccessArticle

Binder-Free Fe-N-C-O Bifunctional Electrocatalyst in Nickel Foam for Aqueous Zinc–Air Batteries

by Jorge González-Morales, Jadra Mosa and Mario Aparicio

Batteries 2025, 11(4), 159; https://doi.org/10.3390/batteries11040159 - 17 Apr 2025

Abstract

The development of efficient, sustainable, and cost-effective catalysts is crucial for energy storage technologies, such as zinc–air batteries (ZABs). These batteries require bifunctional catalysts capable of efficiently and selectively catalyzing oxygen redox reactions. However, the high cost and low selectivity of conventional catalysts [...] Read more.

The development of efficient, sustainable, and cost-effective catalysts is crucial for energy storage technologies, such as zinc–air batteries (ZABs). These batteries require bifunctional catalysts capable of efficiently and selectively catalyzing oxygen redox reactions. However, the high cost and low selectivity of conventional catalysts hinder the large-scale integration of ZABs into the electric grid. This study presents binder-free Fe-based bifunctional electrocatalysts synthesized via a sol–gel method, followed by thermal treatment under ammonia flow. Supported on nickel foam, the catalyst exhibits enhanced activity for both the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), essential for ZAB operation. This work addresses two critical challenges in the development of ZABs: first, the replacement of costly cobalt or platinum-group-metal (PGM)-based catalysts with an efficient alternative; second, the achievement of prolonged battery performance under real conditions without passivation. Structural analysis confirms the integration of iron nitrides, oxides, and carbon, resulting in high conductivity and catalytic stability without relying on precious or cobalt-based metals. Electrochemical tests reveal that the catalyst calcined at 800 °C delivers superior performance, achieving a four-electron ORR mechanism and prolonged operational life compared to its 900 °C counterpart. Both catalysts outperform conventional Pt/C-RuO₂ systems in stability and selective bifunctionality, offering a more sustainable and cost-effective alternative. The innovative combination of nitrogen, carbon, and iron compounds overcomes limitations associated with traditional materials, paving the way for scalable, high-performance applications in renewable energy storage. This work underscores the potential of transition metal-based catalysts in advancing the commercial viability of ZABs. Full article

(This article belongs to the Special Issue Emerging Materials and Technologies for Post-Lithium-Ion Batteries—2nd Edition)

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15 pages, 2332 KiB

Open AccessArticle

Preparation of Mesoporous Boron-Doped Porous Carbon Derived from Coffee Grounds via Hybrid Activation for Carbon Capture and Storage

by Hyeon Hye Kim, Kay-Hyeok An and Byung-Joo Kim

Batteries 2025, 11(4), 158; https://doi.org/10.3390/batteries11040158 - 17 Apr 2025

Viewed by 22

Abstract

The increasing concentration of carbon dioxide (CO₂) in the atmosphere necessitates the development of efficient carbon capture and storage (CCS) technologies. Among these, adsorption-based methods using porous carbon (PC) have attracted considerable attention due to their low energy requirements and cost-effectiveness. [...] Read more.

The increasing concentration of carbon dioxide (CO₂) in the atmosphere necessitates the development of efficient carbon capture and storage (CCS) technologies. Among these, adsorption-based methods using porous carbon (PC) have attracted considerable attention due to their low energy requirements and cost-effectiveness. Biomass waste-derived porous carbon is particularly attractive as a sustainable alternative, offering environmental benefits and high-value applications with low costs. In this study, coffee grounds (CGs) were selected as a precursor due to their abundance and cost-effectiveness compared with other biomass wastes. To improve the pore characteristics of CG-derived carbon (CCG), boric acid treatment was applied during carbonization followed by steam activation to prepare boron-doped CG-derived porous carbon (B-PCG). The N₂/77K adsorption–desorption isotherms revealed a significant increase in the specific surface area and total pore volume of B-PCG from 1590 m²/g and 0.71 cm³/g to 2060 m²/g and 1.01 cm³/g, respectively, compared with PCG. Furthermore, high pressure CO₂ adsorption analysis at 298 K up to 50 bar showed an approximately 50% improvement in CO₂ adsorption capacity for B-PCG compared with PCG. These results suggest that boron doping is an effective strategy to optimize the pore structure and adsorption performance of biomass-derived porous carbon materials for CCS application. Full article

(This article belongs to the Special Issue Advanced Carbon-Based Materials for Next-Generation Batteries and Supercapacitors)

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19 pages, 257 KiB

Open AccessReview

Advances in Standardised Battery Testing for Enhanced Safety and Innovation in Electric Vehicles: A Comprehensive Review

by Márton Pepó, Soma Fullér, Tibor Cseke and Zoltán Weltsch

Batteries 2025, 11(4), 157; https://doi.org/10.3390/batteries11040157 - 16 Apr 2025

Viewed by 120

Abstract

Standardised battery tests are essential for evaluating the safety, reliability, and performance of modern battery technologies, especially with the rapid emergence of innovations such as solid-state and lithium–sulphur batteries. This review reveals critical shortcomings in current international standards (e.g., IEC, IEEE, SAE), which [...] Read more.

Standardised battery tests are essential for evaluating the safety, reliability, and performance of modern battery technologies, especially with the rapid emergence of innovations such as solid-state and lithium–sulphur batteries. This review reveals critical shortcomings in current international standards (e.g., IEC, IEEE, SAE), which often do not keep pace with technological developments and are not harmonised across regions, limiting their effectiveness in real-world applications. The paper stresses the need for the continuous review of test protocols through collaboration between researchers, manufacturers, and regulators. A detailed case study of the BYD Dolphin battery demonstrates the practical importance of comprehensive testing in real-world conditions, spanning electrical, thermal, and mechanical ranges. The review concludes that up-to-date, harmonised, and scenario-specific test methods are needed to ensure accurate battery assessment, support global comparability, and enable the safe introduction of next-generation batteries for electric mobility and energy storage. Future work should prioritise operational monitoring, open access data sharing, and the development of sustainability-focused practices such as recycling and reclamation. Full article

(This article belongs to the Section Battery Performance, Ageing, Reliability and Safety)

15 pages, 5960 KiB

Open AccessArticle

The Use of Cognate Cosolvent to Mediate Localized High-Concentration Electrolytes for High-Voltage and Long-Cycling Lithium-Metal Batteries

by Ying Hu, Dandan Wang, Qijie Yu, Ziyi He, Fengrui Deng, Hao Yan, Tinglu Song, Jin-Cheng Zheng and Yang Dai

Batteries 2025, 11(4), 156; https://doi.org/10.3390/batteries11040156 - 15 Apr 2025

Viewed by 76

Abstract

Localized high-concentration electrolytes (LHCEs) are promising systems for improving the high-voltage performance and interfacial stability of lithium-metal batteries (LMBs). Unfortunately, they are always challenged by liquid–liquid phase separation during solution preparation. Further investigation is always required when the prepared electrolyte has encountered liquid–liquid [...] Read more.

Localized high-concentration electrolytes (LHCEs) are promising systems for improving the high-voltage performance and interfacial stability of lithium-metal batteries (LMBs). Unfortunately, they are always challenged by liquid–liquid phase separation during solution preparation. Further investigation is always required when the prepared electrolyte has encountered liquid–liquid phase separation previously. Here, we propose a “cognate cosolvent” strategy to mediate phase-separated LiBF₄/fluoroethylene carbonate (FEC)|ethyl trifluoroacetate (TFAE) mixtures with ethyl acetate (EA), forming effective LiBF₄/FEC/EA/TFAE-based LHCEs (B-LHCEs). Because of their unique solvation structure, the B-LHCEs exhibit high oxidative stability, facilitating Li⁺ transport. The optimized B-LHCEs help single-crystal LiMn_0.8Mn_0.1Co_0.1O₂/Li batteries form robust interphases, improving interfacial stability. As a result, distinct performance can be obtained (4.5 V, 500 cycles, ~90%, 1400, ~70%; 25 C, 128 mAh g⁻¹, 4.7 V, 500, 82.5%). This work turns the “impossible” into an “effective” high-voltage electrolyte design, transcending the previous paradigms of electrolyte investigation and enriching LHCE preparation research. Full article

(This article belongs to the Special Issue Emerging Materials and Technologies for Post-Lithium-Ion Batteries—2nd Edition)

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17 pages, 3734 KiB

Open AccessArticle

Tailoring Two-Dimensional NiFeCo-Layered Double Hydroxide onto One-Dimensional N-Doped CNTs for High-Performance Bifunctional Air Electrodes in Flexible Zinc–Air Batteries

by Yeon-Woo Kim, Ayeon Lee and Sung Hoon Ahn

Batteries 2025, 11(4), 155; https://doi.org/10.3390/batteries11040155 - 15 Apr 2025

Viewed by 90

Abstract

The development of bifunctional air electrodes with high activity and durability is essential for advancing flexible zinc–air batteries. Herein, a hierarchical electrode structure is designed by growing N-doped carbon nanotubes (CNTs) on copper foam, where CNTs serve as highly active oxygen reduction reaction [...] Read more.

The development of bifunctional air electrodes with high activity and durability is essential for advancing flexible zinc–air batteries. Herein, a hierarchical electrode structure is designed by growing N-doped carbon nanotubes (CNTs) on copper foam, where CNTs serve as highly active oxygen reduction reaction (ORR) sites. The controlled deposition of NiFeCo-layered double hydroxide (LDH) nanosheets, optimized to maintain ORR activity while enhancing oxygen evolution reaction (OER) performance, enables a finely tuned bifunctional catalyst. This architecture achieves outstanding electrochemical properties, requiring only 0.897 V vs. RHE and 1.446 V vs. RHE to reach 10 mA cm⁻² in 1 M KOH, thereby minimizing overpotentials. When implemented as an air electrode in a quasi-solid-state zinc–air battery, the system demonstrates remarkable cycling stability, sustaining performance for over 300 h. Furthermore, a 16 cm² pouch-type zinc–air battery delivers a high discharge capacity of 0.62 Ah, highlighting the scalability of this design. This work presents a robust and scalable strategy for developing high-performance bifunctional air electrodes, offering a promising route for next-generation flexible energy storage systems. Full article

(This article belongs to the Special Issue Two-Dimensional Materials for Battery Applications)

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14 pages, 4189 KiB

Open AccessArticle

Big Data Study of the Impact of Residential Usage and Inhomogeneities on the Diagnosability of PV-Connected Batteries

by Fahim Yasir, Saeed Sepasi and Matthieu Dubarry

Batteries 2025, 11(4), 154; https://doi.org/10.3390/batteries11040154 - 15 Apr 2025

Viewed by 119

Abstract

Grid-connected battery energy storage systems are usually used 24/7, which could prevent the utilization of typical diagnosis and prognosis techniques that require controlled conditions. While some new approaches have been proposed at the laboratory level, the impact of real-world conditions could still be [...] Read more.

Grid-connected battery energy storage systems are usually used 24/7, which could prevent the utilization of typical diagnosis and prognosis techniques that require controlled conditions. While some new approaches have been proposed at the laboratory level, the impact of real-world conditions could still be problematic. This work investigates both the impact of additional residential usage on the cells while charging and of inhomogeneities on the diagnosability of batteries charged from photovoltaic systems. Using Big-Data synthetic datasets covering more than ten thousand possible degradations, we will show that these impacts can be accommodated to retain good diagnosability under auspicious conditions to reach average RMSEs around 2.75%. Full article

(This article belongs to the Special Issue Artificial Intelligence-Based State-of-Health Estimation of Lithium-Ion Batteries—2nd Edition)

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34 pages, 8194 KiB

Open AccessArticle

Optimisation of Solid-State Batteries: A Modelling Approach to Battery Design

by Jan Felix Plumeyer, Friedrich Moesle, Sebastian Wolf, Henrik Born, Heiner Hans Heimes and Achim Kampker

Batteries 2025, 11(4), 153; https://doi.org/10.3390/batteries11040153 - 14 Apr 2025

Viewed by 68

Abstract

Solid-state batteries (SSBs) present a promising advancement in energy storage technology, with the potential to achieve higher energy densities and enhanced safety compared to conventional lithium-ion batteries. However, their commercialisation is hindered by technical limitations and fragmented research efforts that predominantly focus on [...] Read more.

Solid-state batteries (SSBs) present a promising advancement in energy storage technology, with the potential to achieve higher energy densities and enhanced safety compared to conventional lithium-ion batteries. However, their commercialisation is hindered by technical limitations and fragmented research efforts that predominantly focus on materials or individual performance parameters. This narrow scope limits SSB design and optimisation, potentially delaying the transition to commercial cells. Addressing these challenges requires a systematic framework that integrates key design and performance considerations. This study introduces a modelling framework that addresses these challenges by offering a systematic approach to SSB design. The model streamlines the design process by enabling users to define material selections and cell configurations while calculating key performance indicators (KPIs), such as energy density, power density, and resistance, as well as the specifications required for cell manufacturing. A material compatibility validation feature ensures appropriate selection of anode, cathode, and electrolyte materials, while an integrated sensitivity analysis (SA) function identifies critical design parameters for performance optimisation. The model’s accuracy and applicability were validated through comparisons with experimental data, established design frameworks, and the reverse-engineering of commercial SSB prototypes. Results show that the model predicts energy densities within a ±4% deviation in most cases. Additionally, the application of SA highlights its effectiveness in refining design parameters and optimising cell configurations. Despite certain limitations, the model remains a valuable tool in the early stages of battery concept development. It offers researchers and industry professionals a practical means to assess the feasibility of SSB designs and support future scale-up and industrialisation efforts. Full article

(This article belongs to the Section Battery Modelling, Simulation, Management and Application)

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34 pages, 38166 KiB

Open AccessReview

Gas Generation in Lithium-Ion Batteries: Mechanisms, Failure Pathways, and Thermal Safety Implications

by Tianyu Gong, Xuzhi Duan, Yan Shan and Lang Huang

Batteries 2025, 11(4), 152; https://doi.org/10.3390/batteries11040152 - 13 Apr 2025

Viewed by 175

Abstract

Gas evolution in lithium-ion batteries represents a pivotal yet underaddressed concern, significantly compromising long-term cyclability and safety through complex interfacial dynamics and material degradation across both normal operation and extreme thermal scenarios. While extensive research has focused on isolated gas generation mechanisms in [...] Read more.

Gas evolution in lithium-ion batteries represents a pivotal yet underaddressed concern, significantly compromising long-term cyclability and safety through complex interfacial dynamics and material degradation across both normal operation and extreme thermal scenarios. While extensive research has focused on isolated gas generation mechanisms in specific components, critical knowledge gaps persist in understanding cross-component interactions and the cascading failure pathways it induced. This review systematically decouples gas generation mechanisms at cathodes (e.g., lattice oxygen-driven CO₂/CO in high-nickel layered oxides), anodes (e.g., stress-triggered solvent reduction in silicon composites), electrolytes (solvent decomposition), and auxiliary materials (binder/separator degradation), while uniquely establishing their synergistic impacts on battery stability. Distinct from prior modular analyses, we emphasize that: (1) emerging systems exhibit fundamentally different gas evolution thermodynamics compared to conventional materials, exemplified by sulfide solid electrolytes releasing H₂S/SO₂ via unique anionic redox pathways; (2) gas crosstalk between components creates compounding risks—retained gases induce electrolyte dry-out and ion transport barriers during cycling, while combustible gas–O₂ mixtures accelerate thermal runaway through chain reactions. This review proposes three key strategies to suppress gas generation: (1) oxygen lattice stabilization via dopant engineering, (2) solvent decomposition mitigation through tailored interphases engineering, and (3) gas-selective adaptive separator development. Furthermore, it establishes a multiscale design framework spanning atomic defect control to pack-level thermal management, providing actionable guidelines for battery engineering. By correlating early gas detection metrics with degradation patterns, the work enables predictive safety systems and standardized protocols, directly guiding the development of reliable high-energy batteries for electric vehicles and grid storage. Full article

(This article belongs to the Special Issue High-Safety Lithium-Ion Batteries: Basics, Progress and Challenges)

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21 pages, 18354 KiB

Open AccessArticle

On the Morphological Evolution with Cycling of a Ball-Milled Si Slag-Based Electrode for Li-Ion Batteries

by Alexandre Heitz, Victor Vanpeene, Samuel Quéméré, Natalie Herkendaal, Thierry Douillard, Isaac Martens, Marta Mirolo and Lionel Roué

Batteries 2025, 11(4), 151; https://doi.org/10.3390/batteries11040151 - 11 Apr 2025

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Abstract

A Si/SiC/SiO₂ (53/44/3 wt.%) composite is evaluated as an anode material for Li-ion batteries. This material, a result of the high-energy ball-milling of a by-product of the carbothermal reduction of silica (Si slag), is predominantly made up of micrometric particles of amorphous [...] Read more.

A Si/SiC/SiO₂ (53/44/3 wt.%) composite is evaluated as an anode material for Li-ion batteries. This material, a result of the high-energy ball-milling of a by-product of the carbothermal reduction of silica (Si slag), is predominantly made up of micrometric particles of amorphous or short-range order Si in which submicrometric SiC inclusions are dispersed. Its capacity is 860 mAh g⁻¹ (1.7 mAh cm⁻²) after 200 cycles in half-cell configuration and 1.6 mAh cm⁻² after 70 cycles in full-cell. The SiC component is not electroactive for lithiation but plays a key role in the electrode stability by preventing the formation of the c-Li₁₅S_i4 phase, known to accelerate electrode degradation. It is shown that capacity decay with cycling mainly originates from solid electrolyte interphase (SEI) growth rather than particle disconnections. Complementary wide angle X-ray scattering (WAXS) analyses confirm the SEI grows alongside cycling and allows for the highlighting of its major components, namely, Li₂CO₃ and LiF. The morphological evolution of the electrode upon cycling is studied by electrochemical dilatometry, operando optical microscopy, and focused ion beam (FIB) and broad ion beam (BIB) scanning electron microscopy (SEM). No particle cracking is observed. However, reconstructed 3D imaging of the electrodes before and after 10 and 200 cycles clearly shows that the particles progressively evolve a dendritic structure. The SEI grows on and within the particles and induces a significant decrease in the electrode’s porosity and an increase in its thickness. Full article

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19 pages, 19904 KiB

Open AccessArticle

Evaluation of Lithium Battery Cycle Aging Based on Temperature Increase During Charging

by Hanchi Hong, Yu Zhu, Luigi d’Apolito and Shuiwen Shen

Batteries 2025, 11(4), 150; https://doi.org/10.3390/batteries11040150 - 10 Apr 2025

Viewed by 104

Abstract

This study investigates the temperature increase characteristics of lithium-ion batteries under various states of health (SOHs) and proposes an aging assessment method based on temperature increase. The analysis of experimental data reveals that temperature increase behavior varies across different locations on the battery, [...] Read more.

This study investigates the temperature increase characteristics of lithium-ion batteries under various states of health (SOHs) and proposes an aging assessment method based on temperature increase. The analysis of experimental data reveals that temperature increase behavior varies across different locations on the battery, particularly at the center of its large surface area, as the battery ages. This study demonstrates that monitoring surface temperature increase can serve as an effective method for rapid SOH assessment and provides insights into performance degradation and electrode aging. Furthermore, this approach enables the preliminary diagnosis of battery health by tracking temperature changes, without requiring complex equipment, making it highly practical and suitable for widespread application. In addition, this study discusses the potential impact of lithium plating on temperature increase characteristics and its implications for battery safety. Full article

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21 pages, 1231 KiB

Open AccessArticle

Advanced Load Cycle Generation for Electrical Energy Storage Systems Using Gradient Random Pulse Method and Information Maximising-Recurrent Conditional Generative Adversarial Networks

by Steven Neupert, Jiaqi Yao and Julia Kowal

Batteries 2025, 11(4), 149; https://doi.org/10.3390/batteries11040149 - 9 Apr 2025

Viewed by 106

Abstract

The paper presents two approaches to generating load cycles for electrical energy storage systems. A load cycle is described as the operation of an energy storage system. The cycles can include different metrics depending on the storage application. Load cycle analysis using the [...] Read more.

The paper presents two approaches to generating load cycles for electrical energy storage systems. A load cycle is described as the operation of an energy storage system. The cycles can include different metrics depending on the storage application. Load cycle analysis using the rainflow counting method is employed to understand and validate the metrics of the load cycles generated. Current load cycle generation can involve clustering methods, random microtrip methods, and machine learning techniques. The study includes a random microtrip method that utilises the Random Pulse Method (RPM) and enhances it to develop an improved version called the Gradient Random Pulse Method (gradRPM), which includes the control of stress factors such as the gradient of the state of charge (SOC). This method is relatively simple but, in many cases, it fulfills its purpose. Another more sophisticated method to control stress factors has been proposed, namely the Information Maximising-Recurrent Conditional Generative Adversarial Network (Info-RCGAN). It uses a deep learning algorithm to follow a machine learning-based, data-driven load cycle generation approach. Both approaches use the measurement dataset of a BMW i3 over multiple years to generate new synthetic load cycles. After generating the load cycles using both approaches, they are applied in a laboratory environment to evaluate the stress factors and validate how similar the synthetic data are to a real measurement. The results provide insights into generating simulation or testing data for electrical energy storage applications. Full article

(This article belongs to the Special Issue Towards a Smarter Battery Management System: 2nd Edition)

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15 pages, 6710 KiB

Open AccessArticle

Development and Validation of an Electromagnetic Induction-Based Thermal Propagation Test Method for Large-Format Lithium-Ion Battery Systems

by Changyong Jin, Jiangna Gu, Chengshan Xu, Wanlin Wang, Lirong Liu and Xuning Feng

Batteries 2025, 11(4), 148; https://doi.org/10.3390/batteries11040148 - 9 Apr 2025

Viewed by 129

Abstract

This study establishes a standardized framework for thermal propagation test in nickel-7 lithium-ion battery systems through a high-frequency electromagnetic induction heating method. The non-intrusive triggering mechanism enables precise thermal runaway initiation within two seconds through localized eddy current heating (>1200 °C), validated through [...] Read more.

This study establishes a standardized framework for thermal propagation test in nickel-7 lithium-ion battery systems through a high-frequency electromagnetic induction heating method. The non-intrusive triggering mechanism enables precise thermal runaway initiation within two seconds through localized eddy current heating (>1200 °C), validated through cell-level tests with 100% success rate across diverse trigger positions. System-level thermal propagation tests were conducted on two identical battery boxes. The parallel experiments revealed distinct propagation patterns influenced by system sealing quality. In the inadequately sealed system (Box 01), flame formation led to accelerated thermal propagation through enhanced convective and radiative heat transfer. In contrast, the well-sealed system (Box 02) maintained an oxygen-deficient environment, resulting in a controlled sequential propagation pattern. The testing methodology incorporating dummy modules proved efficient for validating thermal protection strategies while optimizing costs. This study contributes to a deeper understanding of thermal runaway propagation mechanisms and the development of standardized testing protocols for large-format battery systems. Full article

(This article belongs to the Special Issue Battery Safety and Fire Prevention in Electric Vehicles)

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37 pages, 8167 KiB

Open AccessReview

Ionic Liquids and Ammoniates as Electrolytes for Advanced Sodium-Based Secondary Batteries

by Pablo Hiller-Vallina, Carmen Miralles, Andrés Parra-Puerto and Roberto Gómez

Batteries 2025, 11(4), 147; https://doi.org/10.3390/batteries11040147 - 9 Apr 2025

Viewed by 177

Abstract

This review aims to provide an up-to-date report on the state of the art of electrolytes based on (quasi-)ionic liquids for sodium batteries. Electrolytes based on conventional ionic liquids are classified into one-anion- and two-anion-type electrolytes according to the number of different anions [...] Read more.

This review aims to provide an up-to-date report on the state of the art of electrolytes based on (quasi-)ionic liquids for sodium batteries. Electrolytes based on conventional ionic liquids are classified into one-anion- and two-anion-type electrolytes according to the number of different anions present in the media. Their application for sodium-based batteries is revised, and the potential advantages of two-anion-type electrolytes are highlighted and rationalized based on the higher tunability of interactions among the different electrolyte components enabled by the presence of two different anionic species. Next, the synthesis and properties of liquid ammonia solvates (aka liquid ammoniates) are presented, with a focus on their use as alternative electrolytes. Attention is paid to some of the outstanding properties of ammoniates, notably, their high conductivity and sodium concentrations, together with their ability to sustain dendrite-free sodium deposition, not only on sodium but also on copper collectors. Finally, the prospects and limitations of these electrolytes for the development of new sodium-based batteries, including anode-less devices, are discussed. Full article

(This article belongs to the Special Issue High-Performance Secondary Batteries: Recent Processes and Future Challenges)

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12 pages, 4129 KiB

Open AccessArticle

Structural Design of Dry-Processed Lithium-Rich Mn-Based Materials with High Loading for Enhanced Energy Density

by Yujie Ma, Haojin Guo, Tai Yang and Zhifeng Wang

Batteries 2025, 11(4), 146; https://doi.org/10.3390/batteries11040146 - 7 Apr 2025

Viewed by 134

Abstract

With the growing demand for electric vehicles and consumer electronics, lithium-ion batteries with a high energy density are urgently needed. Lithium-rich manganese-based materials (LRMs) are known for their high theoretical specific capacity, rapid electron/ion transfer, and high output voltage. Constructing electrodes with a [...] Read more.

With the growing demand for electric vehicles and consumer electronics, lithium-ion batteries with a high energy density are urgently needed. Lithium-rich manganese-based materials (LRMs) are known for their high theoretical specific capacity, rapid electron/ion transfer, and high output voltage. Constructing electrodes with a substantial amount of active materials is a viable method for enhancing the energy density of batteries. In this study, we prepare thick LRM electrodes through a dry process method of binder fibrillation. A point-to-line-to-surface three-dimensional conductive network is designed by carbon agents with various morphologies. This structural design improves conductivity and facilitates efficient ion and electron transport due to close particle contact and tight packing. A high-loading cathode (35 mg cm⁻²) is fabricated, achieving an impressive areal capacity of up to 7.9 mAh cm⁻². Moreover, the pouch cell paired with a lithium metal anode exhibits a remarkable energy density of 949 Wh kg⁻¹. Compared with the cathodes prepared by the wet process, the dry process optimizes the pathways for e⁻/Li⁺ transport, leading to reduced resistance, superior coulombic efficiency, retention over cycling, and minimized side reaction. Therefore, the novel structural adoption of the dry process represents a promising avenue for driving innovation and pushing the boundaries for enhanced energy density for batteries. Full article

(This article belongs to the Special Issue Lithium-Ion Batteries: Design, Preparation, Reaction Mechanisms of Electrode Materials, and Battery Life Evaluation)

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19 pages, 2019 KiB

Open AccessArticle

Early Prediction of Battery Lifetime Using Centered Isotonic Regression with Quantile-Transformed Features

by Muhammad Arslan Khan, Yixing Wang and Benben Jiang

Batteries 2025, 11(4), 145; https://doi.org/10.3390/batteries11040145 - 7 Apr 2025

Viewed by 134

Abstract

The rapid development of lithium-ion (Li-ion) batteries has raised requirements for cycle life prediction to ensure safety and reliability. However, the intricate and nonlinear behavior of the battery degradation process poses significant challenges in accurately predicting its cycle life at an early stage. [...] Read more.

The rapid development of lithium-ion (Li-ion) batteries has raised requirements for cycle life prediction to ensure safety and reliability. However, the intricate and nonlinear behavior of the battery degradation process poses significant challenges in accurately predicting its cycle life at an early stage. This work addresses the battery lifetime prediction problem by leveraging machine learning (ML) methods. First, we apply quantile transformation (QT) to both features and battery cycle lives to improve their correlation. Next, we adopt a centered isotonic regression (CIR) method in our work, a variant of isotonic regression (IR) that centers the feature values and then reduces overfitting to improve model performance. Finally, we perform convex regression (CR) to capture specific patterns in the battery dataset where monotonicity is absent and achieve an overall prediction for battery cycle lives. To validate our proposed method, we have done a comprehensive comparison among several different benchmarks, including elastic net, gradient boosting regression tree, decision tree, support vector machine, random forest, and Gaussian process regression. In contrast to existing methods, our CIR model has shown the best performance, with an average percentage error of 9.8% and a root mean square error of 149 cycles. These experiment results demonstrate the capability and potential of our proposed CIR model in the problem of battery lifetime prediction. Full article

(This article belongs to the Special Issue Machine Learning for Advanced Battery Systems)

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45 pages, 19696 KiB

Open AccessReview

Carbon-Based Thermal Management Solutions and Innovations for Improved Battery Safety: A Review

by Benjamin Tawiah, Emmanuel A. Ofori, Daming Chen, Yang Ming, Yongdan Hou, Hao Jia and Bin Fei

Batteries 2025, 11(4), 144; https://doi.org/10.3390/batteries11040144 (registering DOI) - 7 Apr 2025

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Abstract

The extensive use of lithium-ion batteries and other energy storage systems (ESS) in recent years has resulted in a critical need for effective thermal management solutions that ensure safe and reliable operations. Carbon-based materials (C-bMs) are a promising candidate for addressing the thermal [...] Read more.

The extensive use of lithium-ion batteries and other energy storage systems (ESS) in recent years has resulted in a critical need for effective thermal management solutions that ensure safe and reliable operations. Carbon-based materials (C-bMs) are a promising candidate for addressing the thermal challenges in ESS due to their unique thermal, electrical, and structural properties. This article provides a concise overview of C-bM thermal management solutions for improved battery safety. The key thermal management requirements and failure modes associated with battery systems are highlighted, underscoring the importance of effective battery thermal management (BTM). Various forms of C-bMs, including graphite, graphene, carbon nanotubes, carbon foams, nanodiamonds, and graphdiyne, are examined for their potential applications in battery thermal management systems. The recent innovations and advancements in C-bM thermal management solutions, such as phase change composites, heat pipes, and thermal interface materials, are highlighted. Furthermore, the latest research trends focus mainly on the development of hybrid battery thermal management solutions, carbon-based aerogels, and complex C-bM structures with tailored thermal pathways for optimized thermal management. Most of the current innovations are still at the laboratory scale; hence, future research efforts will be focused on developing integrated multi-functional C-bMs, sustainable and scalable manufacturing techniques, self-healing C-bMs composites, intelligent C-bMs, and further explorations of uncommon C-bMs. These advancements are bound to enhance performance, sustainability, and application-specific adaptations for BTM. This article provides valuable insights for researchers, and stakeholders interested in leveraging C-bMs for BTM. Full article

(This article belongs to the Special Issue Battery Thermal Performance and Management: Advances and Challenges)

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15 pages, 1904 KiB

Open AccessArticle

Design of a High-Voltage Insulation Resistance Detection System for Commercial Vehicles

by Feng Guo, Danping She, Xinfeng Zhang and Yue Han

Batteries 2025, 11(4), 143; https://doi.org/10.3390/batteries11040143 - 7 Apr 2025

Viewed by 108

Abstract

Based on the safety monitoring requirements of power batteries for new energy commercial vehicles, this study proposes a battery insulation detection method utilizing the bridge method in combination with existing insulation detection techniques. Through optimization and improvement of this methodology, an insulation detection [...] Read more.

Based on the safety monitoring requirements of power batteries for new energy commercial vehicles, this study proposes a battery insulation detection method utilizing the bridge method in combination with existing insulation detection techniques. Through optimization and improvement of this methodology, an insulation detection system for new energy commercial vehicle power batteries was developed, along with a dynamic online calculation method for insulation resistance. Comprehensive experimental testing under multiple operational conditions demonstrates that the proposed system achieves a measurement accuracy with errors below 5% for insulation resistance. Furthermore, the system exhibits significant advantages in dynamic real-time monitoring capabilities and operational reliability. Full article

(This article belongs to the Topic Advanced Electric Vehicle Technology, 2nd Volume)

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15 pages, 4298 KiB

Open AccessArticle

Synthesis of Cathode Material Li₂FeTiO₄ for Lithium-Ion Batteries by Sol–Gel Method

by Pengqing Hou, Qi Sun, Shengxue Yan, Guanglong Li, Yingdong Qu and Shaohua Luo

Batteries 2025, 11(4), 142; https://doi.org/10.3390/batteries11040142 - 6 Apr 2025

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Abstract

The development of a simple and reliable strategy to synthesize cathode materials is crucial for achieving the overall high performance of rechargeable lithium batteries, which has proved to be quite challenging. Herein, we report a simple sol–gel method for the synthesis of Li [...] Read more.

The development of a simple and reliable strategy to synthesize cathode materials is crucial for achieving the overall high performance of rechargeable lithium batteries, which has proved to be quite challenging. Herein, we report a simple sol–gel method for the synthesis of Li₂FeTiO₄ cathode materials. The reaction mechanism of Li₂FeTiO₄ crystals can be divided into five stages: including the breakage of the coordination bond; the thermal decomposition of citric acid; the thermal decomposition of metal salts and the reduction of trivalent iron and the formation of Li₂FeTiO₄ crystals. Finally, the optimum calcination temperature for the preparation of Li₂FeTiO₄ cathode materials was explored. The Li₂FeTiO₄ cathode material prepared at 700 °C provides a discharge-specific capacity of 121.3 mAh/g in the first cycle and capacity retention of 89.2%. Our results provide new insights into the application of Li₂FeTiO₄ cathode materials. Full article

(This article belongs to the Special Issue Multifunctional Electrode Materials for Sustainable Energy Storage Devices)

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27 pages, 15381 KiB

Open AccessArticle

Design Optimization of Bionic Liquid Cooling Plate Based on PSO-BP Neural Network Surrogate Model and Multi-Objective Genetic Algorithm

by Jiaming Liu, Wenlin Yuan, Yapeng Zhou and Hengyun Zhang

Batteries 2025, 11(4), 141; https://doi.org/10.3390/batteries11040141 - 5 Apr 2025

Viewed by 86

Abstract

In this study, the particle swarm optimization (PSO) and back propagation neural network (BPNN) surrogate model in combination with a multi-objective genetic algorithm are developed for the design optimization of a bionic liquid cooling plate with a spider-web channel structure. The single-factor sensitivity [...] Read more.

In this study, the particle swarm optimization (PSO) and back propagation neural network (BPNN) surrogate model in combination with a multi-objective genetic algorithm are developed for the design optimization of a bionic liquid cooling plate with a spider-web channel structure. The single-factor sensitivity analysis is first conducted based on the numerical simulation approach, identifying three key factors as design variables for optimizing design objectives such as maximum temperature (T_max), maximum temperature difference (ΔT_max), and pressure drop (ΔP). Subsequently, the PSO algorithm is used to optimize the parameters of the BPNN structure, thereby constructing the PSO-BPNN surrogate model. Next, the non-dominated sorting genetic algorithm II (NSGA-II) is employed to obtain the Pareto optimal set, and the TOPSIS with the entropy weight method is used to determine the optimal solution, eliminating subjective preferences in decision-making. The results show that the PSO-BPNN model outperforms the traditional BPNN in prediction accuracy for all three objectives. Compared to the initial structure, the T_max and ΔT_max are reduced by 1.09 °C and 0.41 °C in the optimized structure, respectively, with an increase in ΔP by 21.24 Pa. Full article

(This article belongs to the Special Issue Thermal Management System for Lithium-Ion Batteries: 2nd Edition)

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37 pages, 23423 KiB

Open AccessReview

Thermally Stable Carbon Materials from Polybenzoxazines: Structure, Properties, and Supercapacitor Potential

by Thirukumaran Periyasamy, Shakila Parveen Asrafali and Jaewoong Lee

Batteries 2025, 11(4), 140; https://doi.org/10.3390/batteries11040140 - 4 Apr 2025

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Abstract

This review explores the structural and electrochemical characteristics of carbon materials derived from polybenzoxazines, emphasizing their potential in supercapacitors. A detailed analysis of thermal degradation by-products during carbonization reveals distinct competing mechanisms, underscoring the exceptional thermal stability of benzoxazines. These materials exhibit significant [...] Read more.

This review explores the structural and electrochemical characteristics of carbon materials derived from polybenzoxazines, emphasizing their potential in supercapacitors. A detailed analysis of thermal degradation by-products during carbonization reveals distinct competing mechanisms, underscoring the exceptional thermal stability of benzoxazines. These materials exhibit significant pseudocapacitive behavior and excellent charge retention, making them strong candidates for energy storage applications. The versatility of polybenzoxazine-based carbons enables the formation of diverse morphologies—nanospheres, foams, films, nanofibers, and aerogels—each tailored for specific functionalities. Advanced synthesis techniques allow for precise control over porosity at the nanoscale, optimizing performance for supercapacitors and beyond. Their exceptional thermal stability, electrical conductivity, and tunable porosity extend their utility to gas adsorption, catalysis, and electromagnetic shielding. Additionally, their intumescent properties (unique ability to expand when exposed to high heat) make them promising candidates for flame-retardant coatings. The combination of customizable architecture, superior electrochemical performance, and high thermal resistance highlights their transformative potential in sustainable energy solutions and advanced protective applications. Full article

(This article belongs to the Special Issue High-Performance Supercapacitors: Advancements & Challenges)

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18 pages, 3618 KiB

Open AccessReview

Strategies to Suppress Polysulfide Dissolution and Its Effects on Lithium–Sulfur Batteries

by Grace Cheung and Chun Huang

Batteries 2025, 11(4), 139; https://doi.org/10.3390/batteries11040139 - 3 Apr 2025

Viewed by 129

Abstract

Lithium–sulfur batteries (LSBs), with a high energy density (2600

W

h

kg⁻¹) and theoretical specific capacity (1672 mA h g⁻¹), are considered the most promising next-generation rechargeable energy storage devices. However, polysulfide dissolution and the shuttle effect cause severe [...] Read more.

Lithium–sulfur batteries (LSBs), with a high energy density (2600

W

h

kg⁻¹) and theoretical specific capacity (1672 mA h g⁻¹), are considered the most promising next-generation rechargeable energy storage devices. However, polysulfide dissolution and the shuttle effect cause severe capacity fading and the rapid loss of the active material; hence, these must be addressed first. This review provides an overview of various strategies employed to immobilise polysulfides via polysulfide trapping and physical and chemical adsorption using porous cathode designs, heterostructures, functionalised separators, and polymer binders. The working mechanism of each strategy is reviewed and discussed, highlighting their advantages and disadvantages, and they are analysed through comparisons of the battery performance and limitations in terms of practical applications. Finally, the future prospects for the design and synthesis of LSBs to limit polysulfide dissolution are discussed. Full article

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10 pages, 2095 KiB

Open AccessArticle

One-Step Synthesis of Zirconium Sulfide Nanoparticles on Flexible Carbon Cloth for Supercapacitor Application

by Yu-Xuan Wang, Dung-Sheng Tsai, Chu-Jung Huang, Zi-Yu Chen and Chuan-Pei Lee

Batteries 2025, 11(4), 138; https://doi.org/10.3390/batteries11040138 - 31 Mar 2025

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Abstract

Zirconium sulfide nanoparticles (Zr_xS_y) are prepared on a flexible substrate of carbon cloth (CC) via a one-step synthesis approach using the low-pressure chemical vapor deposition (LPCVD) technique. The scanning electron microscopy (SEM) image reveals that the particle sizes are [...] Read more.

Zirconium sulfide nanoparticles (Zr_xS_y) are prepared on a flexible substrate of carbon cloth (CC) via a one-step synthesis approach using the low-pressure chemical vapor deposition (LPCVD) technique. The scanning electron microscopy (SEM) image reveals that the particle sizes are in the range of ca. 3~23 nm with an average value of ~13.02 nm. The synthesized Zr_xS_y nanoparticles are composed of ZrS₃ and Zr₉S₂ phases, which is verified by X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HR-TEM). By using the Zr_xS_y/CC as a supercapacitor flexible electrode, the capacitance extracted from the cyclic voltammetry measurement is 406 C g⁻¹ at a scan rate of 5 mV s⁻¹; the capacitance values obtained from GCD curves at a current density of 0.5 A g⁻¹ and 1 A g⁻¹ are 151 and 134 C g⁻¹, respectively. These results highlight the promising potential of Zr_xS_y as a supercapacitor material for future energy-storage technology. Full article

(This article belongs to the Special Issue High Energy Density Supercapacitors: Acquisition, Characterization, and Application)

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25 pages, 7892 KiB

Open AccessArticle

Study of the Operation of Lead–Acid Battery Electrodes Under Hybrid Battery–Electrolyzer Cycling Profiles

by Elisabeth Lemaire, Lionel Serra, Catherine Arnal, Florence Ardiaca, Daniel Monchal, Nicolas Guillet and Angel Kirchev

Batteries 2025, 11(4), 137; https://doi.org/10.3390/batteries11040137 - 31 Mar 2025

Viewed by 66

Abstract

Flooded lead–acid batteries start producing oxygen and hydrogen during the final stages of charge and subsequent overcharge. The collection of the hydrogen produced allows for an increase in overall energy efficiency and transforms the system into a hybrid device typically referred to as [...] Read more.

Flooded lead–acid batteries start producing oxygen and hydrogen during the final stages of charge and subsequent overcharge. The collection of the hydrogen produced allows for an increase in overall energy efficiency and transforms the system into a hybrid device typically referred to as a “Battolyzer” (battery electrolyzer). The present work explores the feasibility of the above approach through a detailed study of the long-term ageing process of flooded tubular lead–acid cells subjected to various rates of discharge and overcharge, emulating four different scenarios of Battolyzer use, starting from 70% depth of discharge cycling to nearly continuous water electrolysis. The combined results from the electrochemical and corrosion studies showed that the Battolyzer cells’ degradation was driven by the corrosion of the positive current collectors. The progress of the corrosion process was strongly correlated with the amount of hydrogen produced. The increase in the depth of discharge resulted in minor decreases in the corrosion current, indicating that the battery functionality of the Battolyzer was more advantageous than the continuous water electrolysis. Full article

(This article belongs to the Special Issue Electrochemistry of Lead-Acid Batteries)

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25 pages, 1563 KiB

Open AccessReview

Lithium Iron Phosphate Battery Regeneration and Recycling: Techniques and Efficiency

by Alexandra Kosenko, Antonina Bolotova, Konstantin Pushnitsa, Pavel Novikov and Anatoliy A. Popovich

Batteries 2025, 11(4), 136; https://doi.org/10.3390/batteries11040136 - 31 Mar 2025

Viewed by 182

Abstract

This study investigates advanced strategies for r regenerating and recycling lithium iron phosphate (LiFePO₄, LFP) materials from spent lithium-ion batteries. Recovery techniques are categorized into direct regeneration, which restores positive electrode materials with high electrochemical performance, and recycling, which produces intermediate [...] Read more.

This study investigates advanced strategies for r regenerating and recycling lithium iron phosphate (LiFePO₄, LFP) materials from spent lithium-ion batteries. Recovery techniques are categorized into direct regeneration, which restores positive electrode materials with high electrochemical performance, and recycling, which produces intermediate compounds such as lithium carbonate and iron phosphate. Additionally, resynthesis methods are explored to convert recovered precursors into high-quality LFP materials, ensuring their reuse in battery production. Innovative approaches, including carbothermic reduction, doping, and hydrothermal resynthesis, are highlighted for their ability to enhance material properties, improve energy efficiency, and maintain the olivine structure of LFP. Key advancements include the use of eco-friendly reagents, automation, and optimization strategies to reduce environmental impacts and costs. Regenerated and resynthesized positive electrodes demonstrated performance metrics comparable to or exceeding commercial LFP, showcasing their potential for widespread application. This work underscores the importance of closed-loop recycling systems and identifies pathways for scaling, improving economic feasibility, and minimizing the ecological footprint of the lithium-ion battery lifecycle. Full article

(This article belongs to the Special Issue Second Life and Recycling: Perspectives for High-Performance Batteries)

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16 pages, 4022 KiB

Open AccessArticle

Super-Fast Sodium Storage Properties of Nitrogen-Doped Graphene-Based Material Synthesized via Arc-Discharge Method

by Injun Jeon, Chunghun Kim, Minseung Kang, Hyun Woo Kim, Hong Chen, Hye Seon Youn, Myung Jong Kim and Chae-Ryong Cho

Batteries 2025, 11(4), 135; https://doi.org/10.3390/batteries11040135 - 29 Mar 2025

Viewed by 164

Abstract

We investigated the electrochemical performance of undoped artificial graphene-based material (UAG) and N-doped graphene-based material (NAG, ~3.5% nitrogen doping), synthesized by the arc-discharge method, for sodium-ion battery anodes. The NAG demonstrated slightly superior fast-charging capability compared to UAG, achieving a specific capacity of [...] Read more.

We investigated the electrochemical performance of undoped artificial graphene-based material (UAG) and N-doped graphene-based material (NAG, ~3.5% nitrogen doping), synthesized by the arc-discharge method, for sodium-ion battery anodes. The NAG demonstrated slightly superior fast-charging capability compared to UAG, achieving a specific capacity of 46.8 mAh g⁻¹ at 30 A g⁻¹, compared to UAG’s capacity of 36.7 mAh g⁻¹, representing an enhancement of approximately 28%. It also showed high cycle stability, retaining a capacity of 100 mAh g⁻¹ (retention ratio ~99.9%) after 2500 cycles at 5 A g⁻¹, compared to UAG’s retention of 90 mAh g⁻¹ (retention ratio ~95%). The diffusion behavior of the UAG and NAG samples was significantly higher than that of graphite. The improvement in electrochemical properties is attributed to the successful doping of nitrogen in NAG, which results in enhanced electrical conductivity and structural disordering. Full article

(This article belongs to the Section Battery Materials and Interfaces: Anode, Cathode, Separators and Electrolytes or Others)

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27 pages, 3909 KiB

Open AccessReview

Styrene and Its Derivatives Used in Proton Exchange Membranes and Anion Exchange Membranes for Fuel Cell Applications: A Review

by Muhammad Rehman Asghar, Ayesha Zahid, Huaneng Su, Kumar Divya, Muhammad Tuoqeer Anwar and Qian Xu

Batteries 2025, 11(4), 134; https://doi.org/10.3390/batteries11040134 - 29 Mar 2025

Viewed by 222

Abstract

The proton exchange membrane (PEM) is a critical component of fuel cells, responsible for controlling the flow of protons while minimizing fuel crossover through its channels. The commercial membrane commonly used in fuel cells is made of Nafion, which is expensive and prone [...] Read more.

The proton exchange membrane (PEM) is a critical component of fuel cells, responsible for controlling the flow of protons while minimizing fuel crossover through its channels. The commercial membrane commonly used in fuel cells is made of Nafion, which is expensive and prone to swelling when in contact with water. To address these limitations, various polymers have been explored as alternatives to replace the costly Nafion membrane. Styrene, a versatile and cost-effective material, has emerged as a promising candidate. It can be modified into different forms to meet the requirements of a fuel cell membrane. The aromatic rings in styrene can copolymerize with hydrophilic functional groups, enhancing water (H₂O) uptake, proton conductivity, and ion exchange capacity (IEC) of the membrane. Additionally, the hydrophobic nature of styrene helps maintain the structural integrity of the membrane’s channels, reducing excessive swelling and minimizing fuel crossover. The flexible aromatic chains in styrene facilitate the attachment of hydrophilic functional groups, such as sulfonic groups, further improving the membrane’s ion conductivity, IEC, thermal stability, mechanical strength, and oxidative stability. This review article explores the application of styrene and its derivatives in fuel cell membranes, with a focus on proton exchange membrane fuel cells (PEMFCs), direct methanol fuel cells (DMFCs), and anion exchange membrane fuel cells (AEMFCs). Full article

(This article belongs to the Special Issue New Polymer Electrolyte Membranes for Fuel Cells)

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17 pages, 3586 KiB

Open AccessArticle

State of Health Estimation for Lithium-Ion Batteries Based on Transition Frequency’s Impedance and Other Impedance Features with Correlation Analysis

by Mohammad K. Al-Smadi and Jaber A. Abu Qahouq

Batteries 2025, 11(4), 133; https://doi.org/10.3390/batteries11040133 - 29 Mar 2025

Viewed by 164

Abstract

This paper presents data-driven impedance-based state of health (SOH) estimation for commercial lithium-ion batteries across an SOH range of ~96% to ~60%. Battery health indicators at the transition frequency of the battery impedance Nyquist plot are utilized to develop an SOH estimator based [...] Read more.

This paper presents data-driven impedance-based state of health (SOH) estimation for commercial lithium-ion batteries across an SOH range of ~96% to ~60%. Battery health indicators at the transition frequency of the battery impedance Nyquist plot are utilized to develop an SOH estimator based on an artificial neural network (ANN). In addition, two more ANN-based SOH estimators utilizing some impedance magnitude and phase values are developed. Spearman correlation analysis is utilized to identify the frequency points at which the impedance magnitude and phase values show strong correlations with SOH values and are thus utilized as SOH indicators. The performance evaluation of the developed SOH estimators shows that the maximum root mean square error (RMSE) is equal to 1.39%, the maximum mean absolute error (MAE) is equal to 1.25%, the maximum mean absolute percentage error (MAPE) is equal to 1.55%, and the minimum coefficient of determination (R²) is equal to 0.983. Full article

(This article belongs to the Special Issue Artificial Intelligence-Based State-of-Health Estimation of Lithium-Ion Batteries—2nd Edition)

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14 pages, 6555 KiB

Open AccessArticle

Analysis and Investigation of Diffusion-Induced Stress in Lithium-Ion Particle Through Elastic-Viscoplastic Model of Binder

by Juanhua Cao and Yafang Zhang

Batteries 2025, 11(4), 132; https://doi.org/10.3390/batteries11040132 - 29 Mar 2025

Viewed by 138

Abstract

During the charging and discharging process of lithium-ion batteries, lithium-ions are embedded and removed from the active particles, leading to volume expansion and contraction of the active particles, and hence diffusion-induced stress (DIS) is generated. DIS leads to fatigue damage of the active [...] Read more.

During the charging and discharging process of lithium-ion batteries, lithium-ions are embedded and removed from the active particles, leading to volume expansion and contraction of the active particles, and hence diffusion-induced stress (DIS) is generated. DIS leads to fatigue damage of the active particles during periodic cycling, causing battery aging and capacity degradation. This article establishes a two-dimensional particle-binder system model in which a linear elastic model is used for the active particle, and an elastic-viscoplastic model is used for the binder. The state of charge, stress, and strain of the particle-binder system under different charge rates are investigated. The simulation results show that the location of particle crack excitation is related to two factors: the concentration gradient of lithium-ion and the binder confinement effect. Under a lower charge rate, the crack excitation position of the particle located at the edge of the particle-binder interfacial (PBI) is mainly attributed to the binder confinement effect, while under a higher charge rate, the crack excitation position occurs at the center of the particle due to the dominance of concentration gradient effect. Furthermore, analysis reveals that the binder undergoes plastic deformation due to the traction force caused by particle expansion, which weakens the constraint on the particle and prevents PBI debonding. Finally, a binder with lower stiffness and higher yield strength behavior is recommended for rapid stress release of particles and could reduce plastic deformation of the binder. Full article

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