A battery internal short-circuit detection method based on capacity increment curve characteristics

Abstract

The invention relates to a method for detecting a short circuit in a battery based on the characteristics of a capacity increment curve, comprising the following steps: 1) performing constant current charging / discharging to a battery pack in series; 2) collecting the voltage of each battery cell in the battery pack in series in real time and current; 3) Obtain the capacity increment curve of each battery cell according to the voltage and current of each battery cell; 4) Extract the curve feature of the capacity increment curve of each battery cell as a method to determine whether the battery cell Judgment basis for the occurrence of internal short circuit; 5) Comprehensively determine whether the internal short circuit occurs in the battery cell according to the curve characteristics of the capacity increment curve of each battery cell. Compared with the prior art, the invention has the advantages of accurate detection, high sensitivity and the like.

Description

technical field [0001] The invention relates to the field of battery fault diagnosis, in particular to a battery internal short-circuit detection method based on capacity increment curve characteristics. Background technique [0002] As the requirements for batteries are getting higher and higher, the types of batteries are constantly iteratively updated. At present, lithium-ion batteries are widely used in all walks of life due to their high energy density and light weight. However, due to battery manufacturing defects, batteries are not Reasonable use and other issues, battery safety accidents occur from time to time. During the manufacturing process, it may be due to the mixing of metal particles, electrode wrinkles, and burrs on the edge of the pole piece, which may cause internal short circuits in the battery; during use, complex and harsh operation The environment, such as high temperature, collision, overcharge, etc., will cause damage to the battery diaphragm and cau...

AI Technical Summary

Problems solved by technology

[0002] As the requirements for batteries are getting higher and higher, the types of batteries are constantly iteratively updated. At present, lithium-ion batteries are widely used in all walks of life due to their high energy density and light weight. However, due to battery manufacturing defects, batteries are not Reasonable use and other issues, battery safety accidents occur from time to time. During the manufacturing process, it may be due to the mixing of metal particles, electrode wrinkles, and burrs on the edge of the pole piece, which may cause internal short circuits in the battery; during use, complex and harsh operation The environment, such as high temperature, collision, overcharge, etc., will cause damage to the battery diaphragm and cause an internal short circuit in the battery. It can be seen that at any time during the battery life cycle, the internal short circuit of the battery may occur, and the uncertain internal short circuit The occurrence of the battery is likely to cause thermal runaway of the battery, resulting in the loss of life and property. Therefore, the occurrence and severity of the short circuit in the battery must be detected in time, and then corresponding measures should be taken to ensure the safety of people and property.

[0003] The existing detection technology is mainly based on the detection method of the threshold, that is, by detecting whether the parameters of the battery, such as voltage, current, capacity and temperature, exceed the set threshold after abnormal changes, or the parameters of the battery cells in the battery pack Compared with each other, whether the difference between them exceeds the set threshold value, this kind of internal short circuit detection method requires a long detection time, the detection result is interfered by the set threshold value, and there are inconsistencies between the battery cells themselves Sexual problems, there may be false detections and missed detections

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