Aging mechanisms and thermal stability of aged commercial 18650 lithium ion battery induced by slight overcharging cycling
Aging mechanisms and thermal stability of aged commercial 18650 lithium ion battery induced by slight overcharging cycling
复制标题
轻微过充循环引起老化商用18650锂离子电池的老化机制和热稳定性
DOI：
10.1016/j.jpowsour.2019.227263
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发表时间：
2020-01-01
影响因子：
9.2
通讯作者：
Wang, Qingsong
中科院分区：
文献类型：
--
作者：
Liu, Jialong;Duan, Qiangling;Wang, Qingsong
由于电池组的不一致性和充电装置的故障，锂离子电池会出现轻微的过充电，甚至会导致热失控。基于增量容量分析和电化学阻抗谱，对锂离子电池在微过充循环下的老化行为和机理进行了定性和定量的研究。结果表明，由于活性物质的损失，轻微的过充电加速了电池的老化。而导电损耗对容量衰减的影响较小。锂密度损失的影响处于中等水平。因此，建议采用增量容量分析和阻抗估计的方法来在线检测过充循环。此外，利用扩展体积加速量热仪研究了老化电池的热稳定性。结果表明，老化电池的稳定性变差。在过充电条件下镀锂引起的热稳定性变化中，负极起着关键作用。在70%SOH后，由于阴极的结构损伤，阴极对稳定性起主导作用。
Because of the inconsistency in battery pack and failure of charging device, slight overcharging of lithium ion batteries appears and even causes to thermal runaway. The aging behavior and mechanisms of lithium ion battery under slight overcharging cycling are studied qualitatively and quantitatively based on incremental capacity analysis and electrochemical impedance spectroscopy in this work. The results show that slight overcharging accelerates battery aging because of the loss of active material. While, conductive loss influences capacity fading less. The effect of lithium density loss is in the middle level. So it is suggested that incremental capacity analysis and impedance estimation are used to detect overcharging cycling on-line. Furthermore, the thermal stability of aged batteries are studied using Extended Volume Accelerating Rate Calorimeter. The results show that the stability of aged batteries become worse. The anode plays a key role in the thermal stability changes because of lithium plating under overcharging. The cathode dominates the stability after 70% SOH because of structure damage of cathode.