Water-based multi-layer membrane for lithium ion battery

Abstract

The invention provides a water-based multi-layer membrane for a lithium ion battery. The water-based multi-layer membrane comprises a polymer membrane substrate (A), an inorganic or organic particle coating (B) coating one or two sides of the polymer membrane substrate (A), and an organic particle coating (C) coating the inorganic or organic particle coating (B), wherein the inorganic or organic particle coating (B) is formed by a composition which comprises 15-70wt% of inorganic or organic particles and 30-85wt% of water; the inorganic or organic particles are selected from aluminum oxide, silica, barium sulfate, boehmite or polyimide; the organic particle coating (C) is formed by a composition which comprises 5-30wt% of organic particles and 70-95wt% of water; and the organic particles are selected from polyvinylidene fluoride-hexafluoropropylene, polyacrylonitrile, polyoxyethylene or polymethyl methacrylate.

Description

technical field

[0001] The invention relates to a diaphragm for a lithium ion battery and a lithium ion battery using the diaphragm, in particular to an aqueous multilayer diaphragm for the lithium ion battery and a lithium ion battery using the diaphragm. Background technique

[0002] Due to its good chemical stability and excellent physical properties, microporous polyethylene film is widely used in secondary lithium-ion batteries, such as: mobile phone batteries, notebook batteries, power tool batteries and power car batteries. In the lithium-ion battery, the main function of the separator is to separate the positive and negative electrodes of the battery and prevent short circuit caused by contact between the two electrodes. It is one of the key inner components. The performance of the separator determines the interface structure and internal resistance of the battery, which directly affects the capacity, cycle and safety performance of the battery. A separator with exce...

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