Evaluation method of state of health SOH of cell

Abstract

The invention discloses an evaluation method of state of health SOH of a cell. Through a cell cycle life experiment, effects on the SOH caused by internal resistance, capacity and SOC parameters are obtained. The internal resistance is used as a research standard, and an objective is provided for following algorithm researches. The internal resistance is used as a research object, a cell equivalent circuit module is established, and on the basis of the module, the SOH of the cell is evaluated by use of the D-EKF. Test software in which the VC++ as a development kernel is designed, the D-EKF algorithm is packaged into a software test platform to finish the evaluation of the SOH of a single cell and a display interface of main parameters of the cell is designed at the same time. According to the invention, aiming at the problem of a failure to predict and evaluate life states of each single storage battery, by researching the SOH of the cell, the SOH of the cell is evaluated by use of the D-EKF method; and the test platform based on a VC software environment is designed, so the accuracy of internal resistance value monitoring data and accuracy of evaluation of the SOH of the cell are tested through the test platform at the same time.

Description

Technical field [0001] The invention relates to an estimation method, in particular to an estimation method of battery health SOH. Background technique [0002] With the rapid development of economy and transportation, it has also caused problems such as energy shortages, rising oil prices, and serious urban pollution. In order to meet the ultimate energy choice for the sustainable development of human society, the development of new energy sources that replace coal and oil has been valued by more and more national governments. As an indispensable part of the new energy system, storage batteries have received increasing attention from markets such as large electric vehicles, power tools, solar and wind power storage equipment, UPS, medical instruments and equipment. However, the current battery has many problems, such as poor fast charge and discharge performance, high price, and overcharge and discharge protection problems. In the case of overcharge or abuse, the battery may fi...

AI Technical Summary

Problems solved by technology

[0005] The current research on battery SOH is of great significance. The state-of-health (SOH) of the battery is estimated to be the weak link of current research, and has become the biggest defect of the current battery monitoring system, which directly affects the effective use of battery capacity and reduces the The safety and reliability of battery use, and affect the function of the battery balancing system, making the battery charge and discharge control lack of sufficient reference, which will eventually affect the performance and service life of the battery

[0006] With the wide application of batteries in various fields, the performance monitoring of batteries has gradually been paid attention to. The SOC and SOH of batteries are two important performance monitoring indicators of batteries. However, compared with the research on SOC, the research on SOH is relatively lagging behind. It is estimated that The method is not yet mature, so the accurate estimation of SOH is a hot and difficult point in current research

At present, the estimation methods of SOH are mainly concentrated in the traditional method. The traditional method is mainly based on the battery cycle charge and discharge test, and analyzes the change of battery characteristics to estimate the SOH of the battery. The disadvantages are waste, long test period, Cannot measure online in real time, etc.

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