An Efficient Electrochemical–Thermal Model for a Lithium-Ion Cell by Using the Proper Orthogonal Decomposition Method

The proper orthogonal decomposition method was applied to develop an efficient, reduced order electrochemical–thermal model for a lithium-ion cell. This model was validated for discharge simulations over a wide range of C rates and various cooling conditions of the cell. The reduced order model agrees well with the COMSOL model, a commercial finite element method solver, and requires times less computation time than the COMSOL model. The model predictions indicate that the discharge time or percent of capacity removed from the cell at an end of discharge voltage of 3.0 V depends on the rate of the discharge and heat transfer rate away from the cell. Also, the heat transfer rate determines whether the capacity removed is limited by mass transfer in the solid phase or mass transfer in the electrolyte.