Lithium-ion battery evaluation method and lithium-ion battery detection system

Abstract

The application relates to a lithium-ion battery evaluation method and a lithium-ion battery detection system. The method includes: collecting the voltage signal of the battery to be tested; The minimum value in the time-voltage differential value graph; select N batteries to be tested of the same type, perform the above four steps N times at N different charging rates, obtain N minimum values, and calculate the N to-be-tested batteries respectively. Measure the lithium analysis capacity of the battery; draw the minimum value occurrence time-battery lithium analysis capacity curve; according to the minimum value occurrence time-battery lithium analysis capacity curve, set the qualified time and qualified lithium analysis capacity, and determine when the minimum value corresponds to The resting time of the battery is less than the passing time t s , it is judged that the battery under test is qualified. The application can accurately judge whether lithium precipitation occurs inside the battery to be tested and evaluate the battery to be tested. The battery to be tested is not damaged, the operation is simple, and the application range is wide.

Description

technical field [0001] The present application relates to the technical field of power batteries, in particular to a lithium-ion battery evaluation method and a lithium-ion battery detection system. Background technique [0002] A lithium-ion battery is a rechargeable battery that primarily relies on the movement of lithium ions between the positive and negative electrodes to function. When charging, lithium ions are deintercalated from the positive electrode of the battery, inserted into the negative electrode through the electrolyte, and the negative electrode is in a lithium-rich state; the opposite is true during discharge. In recent years, pure electric vehicles have become an important development direction of electric vehicles because they can truly achieve "zero emissions", and lithium-ion batteries have become an ideal power source for new-generation electric vehicles due to their excellent performance. [0003] However, under extreme working conditions such as low...

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