Method for measuring sealing performance of seal of cylindrical lithium ion battery

Abstract

The invention relates to a method for measuring the sealing performance of a battery, in particular to a method for measuring the sealing performance of a cylindrical lithium ion battery. The method comprises the following steps: step S01, measuring the thickness of rubber rings of the same batch; step S02, sealing the electrical core of a cylindrical lithium ion battery welded with a cap; step S03, cutting the sealed cap from a roller slot; step S04, cutting the cap from the middle; step S05, smoothing the profile of the cap through polishing; step S06, projecting the profile of the cap witha secondary element projector and measuring the thickness of the projected rubber ring; and step S07, calculating the compression ratio of the rubber ring. According to the invention, the rubber ringis measured via the profile of the cap, so conditions after sealing of the cap can be accurately reflected, and the safety failure of the electrical of the cylindrical lithium ion battery is effectively avoided.

Description

technical field [0001] The invention relates to a method for measuring the sealing performance of a battery, in particular to a method for measuring the sealing performance of a cylindrical lithium-ion battery. Background technique [0002] Battery sealing is an indispensable process in the production process of cylindrical lithium-ion batteries, and it is also a key process that directly affects the safety performance and service life of batteries. as attached figure 2 As shown, the cap includes explosion-proof disk 1, top cover 2, auxiliary steel sheet 3, rubber ring 4, orifice gasket 5 and orifice plate 6. In the prior art, there are mainly two methods for measuring the quality of the cell seal. One is the hydraulic method, and the other is the air pressure method. details as follows: [0003] Water pressure method: by injecting water into the battery core, manually squeeze the water with a lever to increase the internal pressure of the battery core, and measure the ma...

AI Technical Summary

Problems solved by technology

Use water to pressurize, after the battery explodes, the water splashes, which is easy to hurt people

When the cell explodes, the pressure cannot replace the pressure on the seal. Generally, the explosion-proof plate of the cap bears the pressure, and the sealing degree of the seal cannot be confirmed.

[0004] Pneumatic method: Similar to the hydraulic method, the internal inflation is used to increase the internal pressure of the cell, and the measurement pressure will also be faced with the pressure of the cap explosion-proof plate, which cannot reflect the degree of sealing at the seal

[0005] The test pressure of the above two measurement methods is the bursting pressure of the battery cell, not the pressure of the seal, so the measurement is not accurate enough to accurately explain the pressure of the seal

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