The magnitude and rate of heat release that leads to thermal runaway of lithium-ion batteries is highly dependent on the composition and material properties of the cathode material. This work considers the thermodynamic heat release with respect to calorimetry measurements for commercialized metal-oxide cathode materials in electrolytes consisting of LiPF₆ in carbonate solvents. Kinetic forms are also developed for prediction of thermal runaway in single cells and cascading failure in groups of cells. This work builds on the examples of legacy models while drawing on more recent data to develop physics-based models with proper dependence on material properties. These models of cathode decomposition in electrolyte complement a recently published study on the thermal decomposition of lithiated graphite in electrolytes.

Sandia National Laboratories is a multi-mission laboratory managed and operated by National Technology and Engineering Solutions of Sandia, LLC., a wholly owned subsidiary of Honeywell International, Inc., for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-NA0003525. SAND2019-4391 A