Single battery and expansion test method thereof

Abstract

The invention relates to a single battery and an expansion test method thereof, the single battery comprises a battery cell, an insulating film, a shell and a cover plate assembly, the insulating filmwraps the battery cell and is accommodated in the shell, the shell is provided with at least one opening, and the cover plate assembly covers the opening of the shell; the outer surface of the insulating film is coated with a marker, and when the battery cell expands to the outer surface of the insulating film to be in contact with the inner surface of the shell, the marker can be printed and dyed to the inner wall of the shell to form an imprint. According to the single battery and the expansion test method thereof, the hard expansion degree of the battery cell can be obtained by measuring the area of the imprint. The area of the air pressure acting surface can be obtained by detecting the area of the maximum imprinting area of the inner wall of the shell when the air in the shell is seriously extruded, so that the maximum air pressure in the shell can be estimated, data guidance is provided for the size design of the shell and the battery cell, and the situation that the sealing performance of the shell is damaged due to the fact that the air pressure in the shell is too high is avoided.

Description

technical field [0001] The invention relates to the technical field of batteries, in particular to a single battery and a swelling test method thereof. Background technique [0002] Common lithium-ion batteries will swell during charge-discharge cycles and standing, and the expansion phenomenon (expansion deformation, expansion force) will bring many adverse effects. For example, expansion will affect battery life and performance, and will also affect the gap between the battery in the module, thereby affecting the heat dissipation of the battery. In addition, expansion will also bring additional requirements for the strength of the end plate of the module. Therefore, in the process of battery development , it is necessary to conduct more accurate tests and more in-depth research on battery expansion. [0003] Battery expansion is divided into soft expansion and hard expansion. Among them, soft expansion refers to the gas production in the battery, and hard expansion refers...

AI Technical Summary

Problems solved by technology

In the current test of the single battery, it is convenient to monitor the change of the core expansion force acting on the shell by using the fixture and the sensor, but because the test device is outside the shell, the detected result is that the soft expansion and the hard expansion are jointly caused Yes, the monitoring results are inaccurate

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