ESTIMATING METHOD FOR STATE-OF-CHARGE OF LITHIUM ION BATTERY

摘要

An estimating method for state-of-charge of a lithium ion battery is provided. The method comprises charging the lithium ion battery and recording the multiple groups ampere-hour integral values, the states-of-charge and the voltage values based on the integral values in the process of charging; choosing the maximum of the multiple groups of ampere-hour integral values as a first ampere-hour integral value, the state-of-charge corresponding to the first ampere-hour integral value as a first state-of-charge, and the voltage value corresponding to the first ampere-hour integral value as a first voltage value; monitoring the battery in real time, and recording the real-time ampere-hour integral value as a second ampere-hour integral value and a second voltage value corresponding to the second ampere-hour integral value; obtaining a second state-of-charge by ampere-hour measurement method; replacing the second state-of-charge with the first state-of-charge if the second state-of-charge is different form the first state-of-charge. The method increases reliability for determining the battery balance, solves the drawback that the state-of-charge of the battery can be corrected only under the working condition of extreme state-of-charge, and reduces the influence on the battery life when fully charging and discharging.