Batteries MDPI

Highly Cited Papers in 2025

“Comprehensive Study of the Gas Volume and Composition Generated by 5 Ah Nickel Manganese Cobalt Oxide (NMC) Li-Ion Pouch Cells Through Different Failure Mechanisms at Varying States of Charge”

by Gemma E. Howard, Katie C. Abbott, Jonathan E. H. Buston, Jason Gill, Steven L. Goddard and Daniel Howard

Batteries 2025, 11(5), 197; https://doi.org/10.3390/batteries11050197

Lithium-ion batteries risk failing when subjected to different abuse tests, resulting in gas and flames. In this study, 5 Ah nickel manganese cobalt oxide (NMC) pouch cells were subjected to external heating; overcharge at rates of 2.5, 5 and 10 A; and nail pe*******on. Tests were conducted in air and N2 atmospheres. Additional external heat tests were performed on cells at 5, 25, 50, and 75% SoC and on two, three, and four cell blocks. Gas volumes were calculated, and the gas composition was given for H2, CO, CO2, C2H4, C2H6, CH4, C3H6, and C3H8. For tests under an air atmosphere at 100% SoC, the volume of gas varied between abuse methods: 3.9 L (external heat), 6.4 L (overcharge), and 8.9 L (nail pe*******on). The gas composition was found to predominantly contain H2, CO2, and CO for all abuse methods; however, higher concentrations of H2 and CO were present in tests performed under N2. External heat tests at different SoCs showed that the gas volume decreased with SoC. Overall, the type of abuse method can have a large effect on the gas volume and composition produced by cell failure.

Keywords:
Li-ion; pouch cell; nickel manganese cobalt oxide; external heat; overcharge; nail pe*******on; gas volume; gas composition

Batteries | Highly Cited Papers in 2025
https://www.mdpi.com/about/announcements/14579

Comprehensive Study of the Gas Volume and Composition Generated by 5 Ah Nickel Manganese Cobalt Oxide (NMC) Li-Ion Pouch Cells Through Different Failure Mechanisms at Varying States of Charge Lithium-ion batteries risk failing when subjected to different abuse tests, resulting in gas and flames. In this study, 5 Ah nickel manganese cobalt oxide (NMC) pouch cells were subjected to external heating; overcharge at rates of 2.5, 5 and 10 A; and nail pe*******on. Tests were conducted in air a...

Highly Cited Papers in 2025

“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
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.

Keywords:
gas generation; lithium-ion batteries; thermal runaway; electrochemical cycling; interfacial reactions

Batteries | Highly Cited Papers in 2025
https://www.mdpi.com/about/announcements/14579

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

Highly Cited Papers in 2025

“Exploiting Artificial Neural Networks for the State of Charge Estimation in EV/HV Battery Systems: A Review”

by Pierpaolo Dini and Davide Paolini

Batteries 2025, 11(3), 107; https://doi.org/10.3390/batteries11030107
Artificial Neural Networks (ANNs) improve battery management in electric vehicles (EVs) by enhancing the safety, durability, and reliability of electrochemical batteries, particularly through improvements in the State of Charge (SOC) estimation. EV batteries operate under demanding conditions, which can affect performance and, in extreme cases, lead to critical failures such as thermal runaway—an exothermic chain reaction that may result in overheating, fires, and even explosions. Addressing these risks requires advanced diagnostic and management strategies, and machine learning presents a powerful solution due to its ability to adapt across multiple facets of battery management. The versatility of ML enables its application to material discovery, model development, quality control, real-time monitoring, charge optimization, and fault detection, positioning it as an essential technology for modern battery management systems. Specifically, ANN models excel at detecting subtle, complex patterns that reflect battery health and performance, crucial for accurate SOC estimation. The effectiveness of ML applications in this domain, however, is highly dependent on the selection of quality datasets, relevant features, and suitable algorithms. Advanced techniques such as active learning are being explored to enhance ANN model performance by improving the models’ responsiveness to diverse and nuanced battery behavior. This compact survey consolidates recent advances in machine learning for SOC estimation, analyzing the current state of the field and highlighting the challenges and opportunities that remain. By structuring insights from the extensive literature, this paper aims to establish ANNs as a foundational tool in next-generation battery management systems, ultimately supporting safer and more efficient EVs through real-time fault detection, accurate SOC estimation, and robust safety protocols. Future research directions include refining dataset quality, optimizing algorithm selection, and enhancing diagnostic precision, thereby broadening ANNs’ role in ensuring reliable battery management in electric vehicles.

Keywords:
battery system; data-driven strategy; Smart Industry 5.0; electric vehicles; Artifical Neural Networks (ANNs); SOC monitoring

Batteries | Highly Cited Papers in 2025
https://www.mdpi.com/about/announcements/14579

Exploiting Artificial Neural Networks for the State of Charge Estimation in EV/HV Battery Systems: A Review Artificial Neural Networks (ANNs) improve battery management in electric vehicles (EVs) by enhancing the safety, durability, and reliability of electrochemical batteries, particularly through improvements in the State of Charge (SOC) estimation. EV batteries operate under demanding conditions, which...

Highly Cited Papers in 2025

“Heteroatom Doping Strategy of Advanced Carbon for Alkali Metal-Ion Capacitors”

by Ti Yin, Yaqin Guo, Xing Huang, Xinya Yang, Leixin Qin, Tianxiang Ning, Lei Tan, Lingjun Li and Kangyu Zou

Batteries 2025, 11(2), 69; https://doi.org/10.3390/batteries11020069

Alkali metal-ion capacitors (AMICs) combine the advantages of the high specific energy of alkali metal-ion batteries (AMIBs) and the high power output of supercapacitors (SCs), which are considered highly promising and efficient energy storage devices. It is found that carbon has been the most widely used electrode material of AMICs due to its advantages of low cost, a large specific surface area, and excellent electrical conductivity. However, the application of carbon is limited by its low specific capacity, finite kinetic performance, and few active sites. Doping heteroatoms in carbon materials is an effective strategy to adjust their microstructures and improve their electrochemical storage performance, which effectively helps to increase the pseudo-capacitance, enhance the wettability, and increase the ionic migration rate. Moreover, an appropriate heteroatom doping strategy can purposefully guide the design of advanced AMICs. Herein, a systematic review of advanced heteroatom (N, S, P, and B)-doped carbon, which has acted as a positrode and negatrode in AMICs (M = Li, Na, and K) in recent years, has been summarized. Moreover, emphasis is placed on the mechanism of single-element doping versus two-element doping for the enhancement in the performance of carbon positrodes and negatrodes, and an introduction to the use of doped carbon in dual-carbon alkali metal-ion capacitors (DC-AMICs) is discussed. Finally, an outlook is given to solve the problems arising when using doped carbon materials in practical applications and future development directions are presented.

Keywords:

alkali metal-ion capacitor; carbon material; heteroatom doping; electrochemical performance

Batteries | Highly Cited Papers in 2025
https://www.mdpi.com/about/announcements/14579

Heteroatom Doping Strategy of Advanced Carbon for Alkali Metal-Ion Capacitors Alkali metal-ion capacitors (AMICs) combine the advantages of the high specific energy of alkali metal-ion batteries (AMIBs) and the high power output of supercapacitors (SCs), which are considered highly promising and efficient energy storage devices. It is found that carbon has been the most widel...