Diaphragm wettability testing device and testing method thereof

Abstract

The invention relates to a diaphragm wettability testing device which comprises a testing frame and a graduated scale, two butterfly clamps are arranged on the testing frame, an electrolyte container is arranged below the two butterfly clamps, a capillary tube is arranged on the electrolyte container, during testing, the two ends of a diaphragm to be tested are clamped between the two butterfly clamps, and the lower end of the capillary tube is immersed in electrolyte. The upper end of the capillary tube is in contact with the diaphragm to be tested; the graduated scale is transversely arranged on one side of the to-be-tested diaphragm; the invention further relates to a diaphragm wettability testing method, the method comprises the steps of: clamping the diaphragm to be tested through the two butterfly clamps, and transversely straightening the to-be-tested diaphragm; conveying the electrolyte in the electrolyte container to the to-be-tested diaphragm for a certain time t through the capillary tube, wherein the time t is counted from the contact of the electrolyte and the to-be-tested diaphragm; reading the diffusion length L of the electrolyte on the to-be-tested diaphragm through a graduated scale; and calculating the numerical value of the infiltration rate v through an infiltration rate formula v=L / (2*t). According to the invention, the electrolyte can be transversely diffused on the diaphragm, and the test precision is high.

Description

technical field [0001] The invention relates to the technical field of lithium battery production, in particular to a separator wettability test device and a test method thereof. Background technique [0002] As the concept of new energy becomes more and more popular, people's attention to lithium batteries has also greatly increased. Lithium batteries mainly include four parts: positive electrode, negative electrode, diaphragm and electrolyte. After injection, it is difficult to test the wettability of the separator to the electrolyte. For the coated separator with poor wettability, it takes a long time to inject the electrolyte; in addition, for the development of ceramic coatings, each formulation needs to be coated with the separator and made into a battery for evaluation The infiltration of the electrolyte is time-consuming and wastes resources. Therefore, some manufacturers have developed diaphragm wettability testing devices. [0003] When the existing diaphragm wet...

AI Technical Summary

Problems solved by technology

[0003] When the existing diaphragm wettability test device is tested, the diaphragm is suspended vertically, the lower end of the diaphragm is immersed in the electrolyte, and the electrolyte is diffused upward on the surface of the diaphragm. By recording the length L of diffusion and the time t of diffusion, the formula The infiltration rate v can be calculated by v=L / t. The diaphragm on the side with a large value of v has good infiltration, and vice versa.

However, due to the influence of gravity, the higher the electrolyte is, the lower the diffusion speed will be, so the test accuracy error is large and the effect is not ideal

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