Method and device for estimating battery state of charge based on electrochemical model

Abstract

The invention provides method and device for battery state-of-charge (SOC) estimation. The method comprises establishing an electrochemical model for a battery; setting an initial value of the current SOC of the battery, and determining an initial distribution of solid-phase lithium ion concentrations in the electrochemical model according to the initial value of the SOC; performing a charge/discharge test on the battery, collecting measured voltage and current of the battery after a first time interval; calculating an output voltage and a distribution of the solid-phase lithium ion concentrations at a current acquisition time based on the measured current and the initial distribution of the solid-phase lithium ion concentrations; and when a voltage difference between the output voltage and the measured voltage is within a preset range, estimating the current SOC value of the battery based on the distribution of the solid-phase lithium ion concentration at the current acquisition time.