Preparation method of lithium battery ceramic compensation diaphragm and lithium battery

Abstract

The invention discloses a preparation method of a lithium battery ceramic compensation diaphragm and a lithium battery. The preparation method of the lithium battery ceramic compensation diaphragm comprises a ceramic particle preparation step, a base material preparation step, a compensation curing molding step, a coating step and a quality inspection step, wherein the ceramic particle preparation step comprises the steps of preparing an inorganic ceramic material into ceramic particles; wherein the maximum diameter of the ceramic particles is 0.05-0.22 micron, the base material preparation step is that the porous material is prepared into a crystalline polymer film, the crystalline polymer film is prepared into a highly-oriented multilayer structure, and the compensation curing forming step is that the multilayer structure is stretched in a high-temperature environment. According to the invention, the ceramic particles are directly compensated into the pores of the porous material, and then the basic diaphragm with the conventional pore diameter is formed, so that under the condition of meeting the same puncture strength and internal resistance, the lithium battery diaphragm has thinner thickness and can be wound for more layers, and the capacity and charge-discharge performance of the lithium battery can be greatly improved.

Description

technical field [0001] The invention belongs to the technical field of lithium batteries, and in particular relates to a preparation method of a lithium battery ceramic compensation diaphragm and a lithium battery. Background technique [0002] Lithium-ion batteries are usually mainly composed of positive electrodes, negative electrodes, separators, electrolytes, and battery casings. In the lithium-ion battery structure, the separator is one of the key inner components. The main function of the diaphragm is to separate the positive and negative electrodes of the battery, prevent the positive and negative electrodes from being directly contacted and short circuit, and at the same time enable the electrolyte ions to pass smoothly during the charging and discharging process of the battery, forming a current, and abnormality occurs when the battery operating temperature When it rises, the migration channel of electrolyte ions is closed, and the current is cut off to ensure the ...

AI Technical Summary

Problems solved by technology

[0003] Lithium battery separators in the prior art are generally polyolefin porous membranes, but due to the thermoplasticity of polyolefin materials, when the battery temperature rises or is locally overheated, the polyolefin materials will shrink and rupture, making the positive and negative electrodes of the battery directly contact, A short circuit occurs, which seriously affects the safety performance of the battery. Although there are ceramic coatings in the prior art, the pure ceramic coating can only improve the performance of the lithium battery separator to a limited extent, and the thickness is too thick, which will still cause the lithium battery to be affected by the temperature in many cases. The influence of the influence is greater, the internal resistance is too large, etc.

Images