Method for rapidly judging excessive ohmic polarization of secondary battery external line

Abstract

The invention discloses a method for rapidly judging the excessive ohmic polarization of a secondary battery external line. Whether the external line ohmic polarization is in a normal range and the test result is reliable are determined by transient voltage change values. According to the invention, the judgment can be made at the beginning of the test, the situation that the abnormal situation can be found by analyzing and comparing the data only after all the tests are finished can be avoided.

Description

technical field [0001] The invention relates to the technical field of battery detection, in particular to a method for quickly judging that the ohmic polarization of an external circuit of a secondary battery is too large. Background technique [0002] Secondary batteries, especially lithium-ion batteries, have become increasingly popular. Especially in recent years, with the rapid development of the new energy vehicle industry, the demand for lithium-ion power batteries has also shown explosive growth. Different from consumer batteries, the actual operating conditions of power batteries are more complicated, and large current charging and discharging often occur. Therefore, for the detection of power batteries, we often involve rate charging and discharging, pulse charging and discharging, etc. Test items. Because the charge and discharge current is large, the ohmic polarization of the external circuit directly affects the voltage change during the test process, which has...

AI Technical Summary

Problems solved by technology

Because the charge and discharge current is large, the ohmic polarization of the external circuit directly affects the voltage change during the test process, which has a great impact on the rate performance and pulse capability; in addition, for power battery modules, battery packs and systems. If the ohmic polarization of the external line is too large, it will not only affect the judgment of the temperature rise result, but also cause local overheating and cause safety accidents

[0003] The current secondary battery test equipment on the market cannot judge whether the ohmic polarization of the external line is too large, so it cannot quickly evaluate the impact of the ohmic polarization of the external line on the performance evaluation of the battery itself. Only after the test is over, through analysis and comparison of data, To find out whether the test results are reliable

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