Thermal explosion energy evaluated by thermokinetic analysis for series- and parallel-circuit NMC lithium battery modules

The self-heating effect and pressure-blasting potential of a C/LiNi(x)MnyCo(1-x-y)O(2) (NMC) lithium battery were evaluated using adiabatic calorimetry. Such batteries are widely used in electric vehicles. Various states of charge (SoCs) of NMC battery modules connected in series and parallel circuits were examined to investigate the exothermic characteristics and thermal explosion energy under an open-circuit voltage (OCV) state. The heat generation and thermal explosion in various NMC battery modules were compared. The runaway reaction inside the cell and pressure dissipating out of the battery casing were assessed. Thermal runaway and explosion occur in a chargeable battery at an OCV state when the battery module fails or heats to an elevated temperature. Various SoCs of NMC modules were tested to measure the variances in temperature and pressure under adiabatic conditions. Electrochemical and chemical reaction kinetics and calorimetric test data from thermal runaways of various NMC modules were evaluated to create a battery thermal explosion energy model including enthalpy change and work. (C) 2020 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.