Modeling analysis of the effect of battery design on internal short circuit hazard in LiNi0.8Co0.1Mn0.1O2/SiOx-graphite lithium ion batteries

• Published in: International journal of heat and mass transfer 2020-06, Vol.153, p.119590, Article 119590
• Main Authors: Liu, Chaoyue, Li, Hang, Kong, Xiangbang, Zhao, Jinbao
• Format: Article
• Language: English
• Subjects: Chemical reactions; Circuit design; Electrodes; Graphite; Heat measurement; Heat sources; Internal short circuit; Laminated battery; Large format; Lithium; Lithium ion battery; Lithium-ion batteries; Multiphysics model; Numerical methods; Product safety; Rechargeable batteries; Short circuits; Thermal analysis; Thermal runaway
• ISSN: 0017-9310; 1879-2189
• DOI: 10.1016/j.ijheatmasstransfer.2020.119590

•Reaction kinetics of NCM811/SiOx-Graphite LIB components acquired through DSC and ARC tests.•Inner processes analysis of LIB thermal runaway through modeling method.•Empirical simplification of complex reactions kinetics for model coupling.•Electrochemical-thermal coupled model is used to investigate internal short circuit.•Relationship between laminated battery design and internal short circuit hazard pattern is analyzed. The internal short circuit is one of the most severe safety hazards to large format lithium ion batteries. This study aims to reproduce the internal short circuit hazard through experimental and numerical methods to give a better understanding of the effect of laminated battery design on thermal abuse tolerance. A thermal abuse reaction model based on LiNi0.8Co0.1Mn0.1O2/SiOx-graphite system is constructed with the assist of differential scanning calorimetry, and accelerating rate calorimetry experiments. The thermal runaway of the sample battery shows a five-stage process, and 11 chemical reactions and other heat sources are sorted out through modeling. Then the model is further simplified and coupled with the electrochemical-thermal model. The whole process of initiation of thermal runaway and heat progression afterward are reproduced. The model is extended to compare batteries with different laminated numbers and electrode sizes on the internal short circuit issue. Results show that different laminate design schemes will result in different hazard patterns. Larger layer number will delay the thermal runaway of the battery, but increase the seriousness of thermal hazard. Thermal tolerance ability can be adjusted without changing battery capacity. This work provides an applicable methodology for tuning layer number and electrode size for battery manufacture for safety concerns.