Method and device for judging the state of health of a battery

Abstract

The invention discloses a method and device for judging the state of health of a battery. The method includes: acquiring one or several characteristic frequency points of a new battery and the electrochemical impedance at the characteristic frequency; wherein, the characteristic frequency points can reflect the Describe the internal state of the battery; based on the characteristic frequency corresponding to the characteristic frequency point of the new battery, excite the old battery to determine the current electrochemical impedance of the old battery; compare the electrochemical imaginary impedance of the new battery and the old battery at the characteristic frequency, Determine the aging degree of the old battery. The solution of the present invention can overcome defects such as high difficulty in testing in the prior art (for example: it is difficult to reflect the aging condition of the electrochemical reaction inside the battery, and often stays in the external characteristics), high cost and short service life, and realize that the test is difficult , low cost and long service life.

Description

technical field [0001] The invention belongs to the technical field of batteries, and in particular relates to a method and device for judging the health state of a battery, in particular to a method for judging the health state of a lithium-ion battery / battery pack and a device corresponding to the method, and more specifically to a A method for judging the state of health of a lithium-ion battery / battery pack by using the characteristic frequency of an electrochemical process, and a device corresponding to the method. Background technique [0002] As the number and frequency of use of electric vehicles continue to increase, how to non-destructively and quickly diagnose the health status of on-board batteries is of great significance to both car owners and car companies. [0003] The internal mass transfer process and electrochemical reaction are very complicated when the battery is working. A good battery health diagnosis method should reflect the changes inside the batter...

AI Technical Summary

Problems solved by technology

[0005] The object of the present invention is to provide a method and device for judging the state of battery health in view of the above defects, so as to solve the problem of difficulty in testing the state of battery health in the prior art and achieve the effect of reducing the difficulty of testing

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