Wang Huaibin, Du Zhiming, Rui Xinyu, Wang Shuyu, Jin Changyong, He Long, Zhang Fangshu, Wang Qinzheng, Feng Xuning
Laboratory of Explosion Science and Technology, Beijing Institute of Technology, Beijing 100084, China; State Key Laboratory of Automotive Safety and Energy, Tsinghua University, Beijing 100084, China; China People's Police University, LangFang 065000, China.
Laboratory of Explosion Science and Technology, Beijing Institute of Technology, Beijing 100084, China.
J Hazard Mater. 2020 Jul 5;393:122361. doi: 10.1016/j.jhazmat.2020.122361. Epub 2020 Feb 21.
The problem of thermal runaway (TR) propagation challenges the safety design of battery packs, because it aggravates the thermal hazards to accidents. There are many unsolved scientific questions in understanding the mechanisms of TR and its propagation behavior for large format lithium-ion batteries (LIBs). LiNiCoMnO(NCM) is considered as one of the most promising cathode materials for lithium-ion batteries LIBs, given its higher energy design and lower cost. However, higher Nickel (Ni) content of cathode material worsens the thermal stability of LIBs. This paper provides a comparative analysis on the TR propagation behavior of NCM battery with different Ni ratios. Results have shown that when the characteristic temperatures of TR {T, T, T}and the specific electrochemical energy of the cell are similar, TR propagation behavior will be similar, no matter what kinds of chemistry the cell has. Observation suggests that the average propagation time within a large format cell is 7-10 s in module tests. Besides, the internal temperature of the cell has an order of NCM622 ≥ NCM523 ≥ NCM111,whereas the mass is ordered by NCM622 > NCM523 > NCM111.This work firstly reports the TR feature in large format LIBs with different Ni ratios, both at cell and module level, providing the guidelines for engineering practice and further theoretical researches.
热失控（TR）传播问题对电池组的安全设计构成挑战，因为它会加剧事故的热危害。在理解大型锂离子电池（LIB）的热失控及其传播行为的机制方面，存在许多尚未解决的科学问题。鉴于其更高的能量设计和更低的成本，锂镍钴锰氧化物（NCM）被认为是锂离子电池最有前途的正极材料之一。然而，正极材料中较高的镍（Ni）含量会降低锂离子电池的热稳定性。本文对不同镍比例的NCM电池的热失控传播行为进行了对比分析。结果表明，当热失控的特征温度{T、T、T}和电池的比电化学能量相似时，无论电池采用何种化学组成，热失控传播行为都会相似。观察表明，在模块测试中，大型电池内的平均传播时间为7 - 10秒。此外，电池的内部温度顺序为NCM622≥NCM523≥NCM111，而质量顺序为NCM622＞NCM523＞NCM111。这项工作首次报告了不同镍比例的大型锂离子电池在电芯和模块层面的热失控特征，为工程实践和进一步的理论研究提供了指导。
