SOC (start of charge) estimation method of automobile power lithium battery

Abstract

The invention discloses an SOC estimation method of an automobile power lithium battery. The method comprises the steps as follows: a, the method is started; b, when he shelving time is smaller than the set time T0, a step c is entered, otherwise a step d is entered; c, an SOC value during the use stoppage of the lithium battery is taken as a current SOC value; d, a real-time power lithium battery SOC value is obtained by the aid of a relation between open-circuit voltage and the SOC, and a step g is enter; e, when the lithium battery is dynamic, a step f is entered, otherwise, the step b is returned to; f, the SOC is estimated with an Ah integral method, and preliminary correction is performed; g, a difference value of the SOC value obtained in the step d and the SOC value estimated with the Ah integral method is judged, if the difference value is smaller than a set absolute value of e, and a step i is entered, otherwise, a step h is entered; h, the obtained SOC value corrects an initial SOC value of the Ah integral method; and I, the method is finished. According to the method, the SOC is corrected from different aspects, error accumulation caused by the Ah integral method for a long time is modified, and the SOC accuracy can be improved.

Description

technical field [0001] The invention belongs to the technical field of automobile power batteries, and relates to a method for estimating the SOC of an automobile power lithium battery. Background technique [0002] For electric vehicles, the power battery is a very common energy storage component, and its performance plays a decisive role in the performance of the vehicle. As one of the most important parameters of power batteries, SOC must be reasonably controlled to make reasonable use of batteries, improve battery life, and extend vehicle driving range. Therefore, the accuracy of SOC estimation is very important. At present, the estimation of domestic and foreign power batteries is still in a development stage, and the accuracy of SOC estimation method is not high. Contents of the invention [0003] In order to improve the estimation accuracy of the SOC of the automobile power lithium battery, the present invention provides an accurate and real-time method for estimat...

AI Technical Summary

Problems solved by technology

Therefore, the accuracy of SOC estimation is very important. At present, the estimation of domestic and foreign power batteries is still in a development stage, and the accuracy of SOC estimation method is not high.

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