Long Chen , Shaohong Zeng , Jiahua Li , Kuijie Li , Ruixin Ma , Jizhen Liu , Weixiong Wu
{"title":"Safety assessment of overcharged batteries and a novel passive warning method based on relaxation expansion force","authors":"Long Chen , Shaohong Zeng , Jiahua Li , Kuijie Li , Ruixin Ma , Jizhen Liu , Weixiong Wu","doi":"10.1016/j.jechem.2025.02.016","DOIUrl":null,"url":null,"abstract":"<div><div>Due to batteries inconsistencies and potential faults in battery management systems, slight overcharging remains a common yet insufficiently understood safety risk, lacking effective warning methods. To illuminate the degradation behavior and failure mechanism of various overcharged states (100% SOC, 105% SOC, 110% SOC, and 115% SOC), multiple advanced in-situ characterization techniques (accelerating rate calorimeter, electrochemical impedance spectroscopy, ultrasonic scanning, and expansion instrument) were utilized. Additionally, re-overcharge-induced thermal runaway (TR) tests were conducted, with a specific emphasis on the evolution of the expansion force signal. Results indicated significant degradation at 110% SOC, including conductivity loss, loss of lithium inventory, and loss of active material accompanied by internal gas generation. These failure behaviors slow down the expansion force rate during re-overcharging, reducing the efficacy of active warnings that depend on rate thresholds of expansion force. Specifically, the warning time for 115% SOC battery is only 144 s, which is 740 s shorter than that for fresh battery, and the time to TR is advanced by 9 min. Moreover, the initial self-heating temperature (<em>T</em><sub>1</sub>) is reduced by 62.4 °C compared to that of fresh battery, reaching only 70.8 °C. To address the low safety of overcharged batteries, a passive overcharge warning method utilizing relaxation expansion force was proposed, based on the continued gas generation after stopping charging, leading to a sustained increase in force. Compared to active methods that rely on thresholds of expansion force rate, the passive method can issue warnings 115 s earlier. By combining the passive and active warning methods, guaranteed effective overcharge warning can be issued 863–884 s before TR. This study introduces a novel perspective for enhancing the safety of batteries.</div></div>","PeriodicalId":15728,"journal":{"name":"Journal of Energy Chemistry","volume":"105 ","pages":"Pages 595-607"},"PeriodicalIF":13.1000,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Energy Chemistry","FirstCategoryId":"92","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S2095495625001640","RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"Energy","Score":null,"Total":0}
引用次数: 0
Abstract
Due to batteries inconsistencies and potential faults in battery management systems, slight overcharging remains a common yet insufficiently understood safety risk, lacking effective warning methods. To illuminate the degradation behavior and failure mechanism of various overcharged states (100% SOC, 105% SOC, 110% SOC, and 115% SOC), multiple advanced in-situ characterization techniques (accelerating rate calorimeter, electrochemical impedance spectroscopy, ultrasonic scanning, and expansion instrument) were utilized. Additionally, re-overcharge-induced thermal runaway (TR) tests were conducted, with a specific emphasis on the evolution of the expansion force signal. Results indicated significant degradation at 110% SOC, including conductivity loss, loss of lithium inventory, and loss of active material accompanied by internal gas generation. These failure behaviors slow down the expansion force rate during re-overcharging, reducing the efficacy of active warnings that depend on rate thresholds of expansion force. Specifically, the warning time for 115% SOC battery is only 144 s, which is 740 s shorter than that for fresh battery, and the time to TR is advanced by 9 min. Moreover, the initial self-heating temperature (T1) is reduced by 62.4 °C compared to that of fresh battery, reaching only 70.8 °C. To address the low safety of overcharged batteries, a passive overcharge warning method utilizing relaxation expansion force was proposed, based on the continued gas generation after stopping charging, leading to a sustained increase in force. Compared to active methods that rely on thresholds of expansion force rate, the passive method can issue warnings 115 s earlier. By combining the passive and active warning methods, guaranteed effective overcharge warning can be issued 863–884 s before TR. This study introduces a novel perspective for enhancing the safety of batteries.
期刊介绍:
The Journal of Energy Chemistry, the official publication of Science Press and the Dalian Institute of Chemical Physics, Chinese Academy of Sciences, serves as a platform for reporting creative research and innovative applications in energy chemistry. It mainly reports on creative researches and innovative applications of chemical conversions of fossil energy, carbon dioxide, electrochemical energy and hydrogen energy, as well as the conversions of biomass and solar energy related with chemical issues to promote academic exchanges in the field of energy chemistry and to accelerate the exploration, research and development of energy science and technologies.
This journal focuses on original research papers covering various topics within energy chemistry worldwide, including:
Optimized utilization of fossil energy
Hydrogen energy
Conversion and storage of electrochemical energy
Capture, storage, and chemical conversion of carbon dioxide
Materials and nanotechnologies for energy conversion and storage
Chemistry in biomass conversion
Chemistry in the utilization of solar energy