Reduced order of electrochemical model for a pouch type high power Li-polymer battery

Abstract

A two dimensional model for a single cell is developed by connecting one dimensional electrochemical micro cell models by current collectors. The model is capable of representing terminal behavior along with internal physical variables that include temperature, potentials and ion flows. However, the model is very computational intensive and needs to be reduced for implementation into real time applications. The order reductions are carried out applying polynomial and state space approach for estimation of concentrations in electrolyte and electrodes. The potentials in the components are solved by iterative method and combined with the reduced order to substantially reduce the computational time. The two models are compared with respect to static and dynamic behavior at terminal voltage at different current rates as a function of state-of-charge (SOC) as well as concentrations of ions in electrodes and electrolyte in the cell. In addition, voltage responses of step current at charging and discharging processes are also compared.