Huang Lang, Xu Gaojie, Du Xiaofan, Li Jiedong, Xie Bin, Liu Haisheng, Han Pengxian, Dong Shanmu, Cui Guanglei, Chen Liquan
Qingdao Industrial Energy Storage Research Institute, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 189 Songling Road, Qingdao, 266101, China.
Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing, 100049, China.
Adv Sci (Weinh). 2021 Jul;8(14):e2100676. doi: 10.1002/advs.202100676. Epub 2021 May 24.
The continuous energy density increase of lithium ion batteries (LIBs) inevitably accompanies with the rising of safety concerns. Here, the thermal runaway characteristics of a high-energy 5 Ah LiNi Co Mn O /graphite pouch cell using a thermally stable dual-salt electrolyte are analyzed. The existence of LiH in the graphite anode side is innovatively identified in this study, and the LiH/electrolyte exothermic reactions and H migration from anode to cathode side are proved to contribute on triggering the thermal runaway of the pouch cell, while the phase transformation of lithiated graphite anode and the O -releasing from cathode are just accelerating factors for thermal runaway. In addition, heat determination during cycling at two boundary scenarios of adiabatic and isothermal environment clearly states the necessity of designing an efficient and smart battery thermal management system for avoiding heat accumulation. These findings will shed promising lights on thermal runaway route map depiction and thermal runaway prevention, as well as formulation of electrolyte for high energy safer LIBs.
锂离子电池（LIBs）能量密度的持续增加不可避免地伴随着安全问题的增多。在此，对采用热稳定双盐电解质的5 Ah高能量锂镍钴锰氧化物/石墨软包电池的热失控特性进行了分析。本研究创新性地确定了石墨阳极侧存在LiH，并证明LiH/电解质放热反应以及H从阳极向阴极侧的迁移是引发软包电池热失控的原因，而锂化石墨阳极的相变和阴极的O释放只是热失控的加速因素。此外，在绝热和等温环境这两种边界情况下循环过程中的热测定清楚地表明，设计高效智能的电池热管理系统以避免热量积累是必要的。这些发现将为热失控路径图描绘和热失控预防以及高能量更安全锂离子电池电解质的配方提供有前景的思路。
