锂离子电池安全状态评估研究进展

Research progress on the safety-state assessment of lithium-ion batteries

锂离子电池安全状态评估综合了影响电池安全的因素,定量获取内外部条件对电池安全的持续影响程度,在全寿命周期内监测和跟踪电池的安全状态,可为故障超前预警和智能运维提供判定依据,对提升系统的安全性和可靠性具有重要意义。然而,锂离子电池失效模式多、影响机制复杂、安全状态定义模糊,目前专家学者对于电池管理系统和大数据平台中的电池安全状态评估结果的可用性和准确性还存在诸多疑问。本文通过对近期相关文献的探讨,综述了当前主流的电池安全状态定义与分级策略,介绍了定性和定量两种电池安全状态评估方法,分析了影响电池安全状态的多种因素及其安全边界。对于电池安全状态影响因素多而复杂的问题,着重总结了电压、环境温度、电流、机械变形、极限外部条件、荷电状态、健康状态、内阻、析锂状态这9种因素对锂离子电池安全的影响机制。最后提出了当前锂离子电池安全状态评估研究在多因素耦合关联机制、安全阈值迁移模型和定量评估方法三方面还存在不足,为接下来的研究指明了发展方向。

The assessment of the state of safety(SOS)of Li-ion batteries(LiB)is required to determine the sustained impact of the internal and external conditions on battery safety,as well as the monitoring of the safety status of batteries throughout their lifecycle.SOS assessment can provide a judgment basis for advance fault warning and intelligent operation and maintenance;this is crucial for improving the security and reliability of the energy storage system.However,several questions still remain to be answered about the usability and accuracy of SOS assessment results in battery management systems or big data platforms.A LiB has many failure modes,a complex influence mechanism,and fuzzy definition of SOS.This paper summarizes the definition and classification,evaluation method,influencing factors,and safety boundary of battery SOS.In addition,the paper summarizes the influence mechanism of nine factors,namely voltage,ambient temperature,current,mechanical deformation,limiting external conditions,state of charge,state of health,internal resistance,and state of Li plating on the safety of LiBs.The shortcomings of the current SOS evaluation of LIBs are discussed based on three aspects,namely the coupling mechanism of multiple factors,security threshold migration model,and quantitative evaluation method.Finally,the paper points out future research direction.