Modeling of the overcharge behavior of lithium-ion battery cells protected by a voltage-switchable resistive polymer layer

Abstract Recently, a novel approach to overcharge protection of Li-ion batteries by voltage-switchable resistive polymer layer, placed between the cathode active mass and the current collector, was reported. The unique feature of the layer under consideration is the ability to increase the electrode resistance when the cathode potential exceeds operating limits, preventing cell overcharge and degradation. Here we extend the full-order Newman model of a lithium-ion battery cell by adding a description of the novel type of overcharge protection layer. The model was used to simulate Constant Current, Constant Voltage, and Constant Power charging modes as well as thermal effects and was implemented in Multiphysics (MP) software (COMSOL Inc., Palo Alto, CA). Comparison of electrochemical responses in the simulated modes demonstrated that the cell protected via the protective layer has advantages when operating at any mode. Therefore, the computational study proves the effectiveness of the usage of the protective layer with switchable resistance. Moreover, this model is a powerful tool for material design and engineering tasks in LIB development as it allows fast and simple estimation of resistance and other parameters’ values that meet a given safety standard.