不同放电功率下的储能用磷酸铁锂电池热失控特性实验研究  

Experimental study of the thermal runaway characteristics of lithium iron phosphate batteries for energy storage under various discharge powers

作　　者：何春汕 王子阳 姚斌[1] HE Chunshan;WANG Ziyang;YAO Bin(State Key Laboratory of Fire Science,University of Science and Technology of China,Hefei 230026,Anhui,China)

机构地区：[1]中国科学技术大学火灾科学国家重点实验室,安徽合肥230026

出　　处：《储能科学与技术》2024年第3期981-989,共9页Energy Storage Science and Technology

摘　　要：以某款52 Ah储能用方形磷酸铁锂电池单体为对象,采用400 W的外部热源、20.8~166.4 W(1~8 h)的恒功率放电以匹配电池工作状态下的热滥用条件,测量电池热失控过程中的表面温度和电压,记录热失控实验现象和关键时间点,对比研究不同放电功率对热滥用诱发热失控进程的影响。结果表明,放电操作会加速热失控的进程,且放电功率越大,热失控越早发生,从不放电到166.4 W恒功率放电,安全阀打开时间缩短了23.4%,热失控触发时间缩短了5.6%;与此同时,四组放电工况由于放出部分能量,最终热失控的严重程度有所降低,放电工况下的热失控最高温度和最大温升速率比不放电工况最高分别下降了9.0%和53.3%;另外,放电操作会造成热失控过程中电压更大的波动,后续电压下降的时间窗口前移至开阀时间附近,这将更有利于利用电压变化对热失控进行预警。总体而言,放电操作在加速热失控进程的同时,降低了热失控最终的严重程度。本工作可对电化学储能电站的日常安全运营和电池管理系统设计提供参考。We report the results of energy-storage experiments on a 52 Ah square Li-FePO_(4)battery.A 400 W external heat source and 20.8—166.4 W(1—8 h rated discharge)discharge power were used to simulate the thermal conditions of the battery under working conditions.The battery surface temperature and voltage were measured during thermal runaway,and the key time points of thermal runaway were recorded to study how discharge power affects thermal-abuse-induced thermal runaway.The results show that discharge accelerates thermal runaway:the higher the discharge power,the earlier the thermal runaway starts.From nondischarge to 166.4 W constant discharge,the opening time of the safety valve is shortened by 23.4%,and the thermal-runaway-triggering time is shortened by 5.6%.At the same time,the release of energy in the four stages of discharge reduces the severity of the thermal runaway,and the three maximum thermal runaway temperatures and the maximum temperature increase during discharge are reduced by 9.0%and 53.3%,respectively,with respect to the nondischarge condition.In addition,discharge increases voltage fluctuations during thermal runaway.The time window for subsequent voltage drop shifts forward to the vicinity of the valve-opening time,which favors using voltage change as an early warning of thermal runaway.Overall,the discharge operation accelerates thermal runaway while reducing its severity.This paper thus provides a reference for the safe daily operation,and the design of a battery-management system for electrochemical energy-storage power plants.

关 键 词：磷酸铁锂电池 热失控 热滥用 放电功率 

分 类 号：TM912[电气工程—电力电子与电力传动]