Method and system for detecting internal short circuit of power battery

Abstract

The invention discloses a method and system for detecting the internal short circuit of a power battery, the method comprising: acquiring the terminal voltage of each battery pack in the power battery; connecting all terminal voltages in series and constructing a closed detection model; calculating a correlation coefficient of each two adjacent terminal voltages, and determining the correlation coefficient as a detection coefficient of the battery pack corresponding to the previous one of the two adjacent terminal voltages; determining whether all the detection coefficients are higher than a set threshold; if so, determining that a short-circuit fault does not occur inside the power battery; if not, determining that the short-circuit fault occurs in the battery packs corresponding to the detection coefficients not higher than the set threshold. By constructing the closed detection model, the method, on one hand, can quickly and effectively detect the short circuit fault of the batteryand ensure the safety of the power battery, and on the other hand, can accurately and effectively position the fault to solve inaccurate and unstable short-circuit detection inside the power battery in the prior art.

Description

technical field [0001] The invention relates to the technical field of power batteries, in particular to a method and system for detecting short circuits inside a power battery. Background technique [0002] Power batteries have been widely used in electric vehicles, and the safety and reliability of power batteries are directly related to the safe use of electric vehicles. The application of power batteries is affected by its characteristics, and has special requirements for ambient temperature and usage methods. In the application process, it is not only necessary to ensure that it operates in a good temperature environment, but also to set a reasonable usage method and detection method. , The reasonable use method ensures the maximum performance of the power battery, and the detection method ensures that the power battery can be found in time when there is a problem, so as to avoid causing greater damage to the power battery or even battery safety accidents. [0003] The...

AI Technical Summary

Problems solved by technology

[0003] The internal short circuit of the power battery is a safety-related problem during the use of the power battery. The following points may cause the internal short circuit of the power battery: First, the power battery is charged at low temperature, which is determined by the performance of the power battery, such as charging at low temperature , the battery is easy to form crystals, and the cumulative growth of crystals will pierce the battery diaphragm, which will cause a short circuit in the power battery; second, in the case of overcharge or overdischarge of the power battery, it will cause irreversible ions. Will cause a short circuit in the power battery

[0004] Since the power battery is generally a single package, there is no direct method to detect the internal short circuit. In the process of use, the method of regular maintenance is generally adopted, and the power battery is regularly tested.

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