Lithium battery equivalent circuit model establishing method considering temperature and SOC double factors

Abstract

The invention relates to a lithium battery equivalent circuit model building method considering temperature and SOC double factors, and the method comprises the steps: designing an orthogonal experiment, building an ECM model and estimating parameters of the ECM model according to the influence of the temperature and SOC factors in the orthogonal experiment design, and building an equivalent circuit model of a lithium battery based on an Arrhenius model and a polynomial model as parameters. The method comprises the following steps of: selecting different segments and orders, estimating model parameters of the OPPA model, loading parameters of the best segments and orders of a prediction result, and substituting the parameters into the OPPA model to obtain parameters of an ECM model, so as to obtain an OPPA-ECM model. According to the method, a two-factor orthogonal test is designed, and an OPPA model is established on the basis of a form of a temperature-affected Arrhenius equation in combination with an SOC-affected polynomial model. The parameters of the ECM model are corrected by using the OPPA, so that the ECM model shows relatively good prediction performance on the EIS impedance spectrum under unknown temperature and SOC conditions.

Description

Technical field [0001] The present invention belongs to the field of battery management, and specifically, a method of establishing a lithium battery equivalent circuit model considering temperature and SOC dual factors. Background technique [0002] The reasonable experimental design can control the test error, guarantee the quality of the test, which makes the test represent, correct and repeat. One of the main roles of test design is to determine the impact of test factors on test indicators. Temperature and SOC are two important factors affecting battery performance, and many documents are studied. For example, Andre et al, a 6.5AH high-power NCM lithium ion battery is used as a test object, and seven temperature levels from -30 ° C to 50 ° C and two factors of 18 SOC levels from 0% to 100%. The entire test contains 119 test points. The temperature level interval is gradually reduced by high temperatures to low temperatures. The SOC level interval is 5% in high SOC and low SO...

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Problems solved by technology

[0004] In view of this, the purpose of the present invention is to overcome the deficiencies in the prior art, provide a kind of lithium battery equivalent circuit model establishment method that considers two factors of temperature and SOC, to solve the problem when the number of factors and the number of levels are large in the prior art , There are too many combinations of comprehensive test levels, and it is usually unbearable for manpower, material resources, financial resources and venues

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