Non-combustible solid-state polymer electrolyte and application thereof in solid-state secondary battery

Abstract

The invention discloses a non-combustible solid-state polymer electrolyte. The non-combustible solid-state polymer electrolyte is characterized by comprising a polyphosphate polymer and a metal salt compound, wherein the mass percent of the metal salt compound accounts for 10-90% of the whole solid-state polymer electrolyte. The solid-state polymer electrolyte is high in phosphorus content, comprises a methyl phosphonic structure, has excellent flame-retardant performance, favorable mechanical property, high ion conductivity, relatively wide electrochemical window and good electrode interfacestability, is incombustible, is particularly applied to a high-safety and high-energy density energy storage battery and has very wide application prospect in the fields of military, aerospace, an electric vehicle and a large-scale energy storage power station.

Description

technical field [0001] The invention relates to a solid polymer electrolyte, in particular to a non-combustible solid polymer electrolyte and its application in solid secondary batteries. Background technique [0002] The electrolytes of existing electrochemical energy storage batteries such as lithium ion batteries mainly include liquid organic carbonate solvents, lithium salts and polyolefin separators. The use of a large amount of organic electrolyte is easy to leak and volatilize, and it is easy to catch fire and burn, and even cause an explosion accident, which affects the safety performance of the battery. On the other hand, the thermal stability of the polyolefin separator is relatively poor. When the battery is heated or under extreme conditions, the separator will shrink or melt, resulting in a short circuit of the battery, resulting in a fire and explosion accident. The all-solid-state lithium battery that replaces the organic liquid electrolyte with a solid elect...

AI Technical Summary

Problems solved by technology

[0004] However, polymer electrolytes commonly used in polymer solid-state electrolytes, such as polyethylene oxide and polycarbonate, are combustible in flames, so it is impossible to ensure that the solid-state batteries made of them are extremely unlikely to cause combustion and explosion accidents.

Some people have studied polyphosphazene solid-state electrolytes, but they have not been widely used due to the complexity of synthesis and high price.

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