Overcharge-to-thermal-runaway behavior and safety assessment of commercial lithium-ion cells with different cathode materials:A comparison study  

作　　者：Zhenpo Wang Jing Yuan Xiaoqing Zhu Hsin Wang Lvwei Huang Yituo Wang Shiqi Xu 

机构地区：[1]National Engineering Laboratory for Electric Vehicles,Beijing Institute of Technology,Beijing 100081,China [2]Collaborative Innovation Center for Electric Vehicles in Beijing,Beijing 100081,China [3]Materials Science and Technology Division,Oak Ridge National Laboratory,Oak Ridge 37831,TN,USA [4]Shanghai Jieneng Automotive Technology Co.,Ltd.,Shanghai 201804,China [5]State-assigned Electric Vehicle Power Battery Testing Center,China North Vehicle Research Institute,Beijing 100072,China

出　　处：《Journal of Energy Chemistry》2021年第4期484-498,共15页能源化学（英文版）

基　　金：supported by the National Natural Science Foundation of China(Nos.U1564206,U1764258);the National Key R&D Program of China(No.2018YFB0105700);the support from China Scholarship Council(No.201806030115);supported by the Department of Energy(DOE),Office of Electricity(OE)at Oak Ridge National Laboratory managed by UL-Battelle LLC under contract DE-AC05-00OR22725。

摘　　要：In this paper,overcharge behaviors and thermal runaway(TR)features of large format lithium-ion(Liion)cells with different cathode materials(LiFePO4(LFP),Li[Ni_(1/3)Co_(1/3)Mn_(1/3)]O_(2)(NCM111),Li[Ni_(0.6)Co_(0.2)Mn_(0.2)]O_(2)(NCM622)and Li[Ni_(0.8)Co_(0.1)Mn_(0.1)]O_(2)(NCM811))were investigated.The results showed that,under the same overcharge condition,the TR of LFP Li-ion cell occurred earlier compared with the NCM Li-ion cells,indicating its poor overcharge tolerance and high TR risk.However,when TR occurred,LFP Li-ion cell exhibited lower maximum temperature and mild TR response.All NCM Liion cells caught fire or exploded during TR,while the LFP Li-ion cell only released a large amount of smoke without fire.According to the overcharge behaviors and TR features,a safety assessment score system was proposed to evaluate the safety of the cells.In short,NCM Li-ion cells have better performance in energy density and overcharge tolerance(or low TR risk),while LFP Li-ion cell showed less severe response to overcharging(or less TR hazards).For NCM Li-ion cells,as the ratio of nickel in cathode material increases,the thermal stability of the cathode materials becomes poorer,and the TR hazards increase.Such a comparison study on large format Li-ion cells with different cathode materials can provide deeper insights into the overcharge behaviors and TR features,and provide guidance for engineers to reasonably choose battery materials in automotive applications.

关 键 词：Lithium-ion battery Cathode materials OVERCHARGE Thermal runaway Overcharge tolerance Safety assessment 

分 类 号：TM912[电气工程—电力电子与电力传动]