In this paper,the safety comparison between the beginning of life(BOL)and the ending of life(EOL)of 125Ah square aluminum shell is selected as three typical research objects:short circuit test,overcharge test and thermal runaway.The results show that the heat released in the thermal stage is equivalent to the heat released at the beginning of the life cycle after about 8000 cycles at room temperature,and the time required to reach the highest temperature point of thermal runaway is longer,and the temperature curve consistency is better.At the end of life,the short-circuit voltage and current waveform changes are consistent.There are sub-high points,which are mainly caused by the decrease of concentration polarization after temperature increase.At the end of life,the overcharge takes less time to reach the target voltage,and there is a chance that the cell will run out of control.This study is helpful to promote the safety research of energy storage batteries in the whole life cycle,which not only provides theoretical and experimental basis for the design and development of long-cycle lithium iron phosphate batteries,but also lays a foundation for the application of high safety,high reliability and high quality products.
关键词
磷酸铁锂电池/储能电芯/方型铝壳/热失控/短路/过充
Key words
Lithium iron phosphate battery/Energy storage cell/Prismatic aluminum-shell/Thermal runaway/Short circuit/Overcharge
维普
万方数据