Ionic-liquid-base polymer electrolyte

Abstract

An ionic liquid material, which is formed by the reaction of organic lithium borates or lithium aluminates and organic compounds containing amido functional groups, is used as a base and compounded with polymer materials to obtain the all-solid-state or gel-state polymer electrolyte material. The polymer electrolyte material has the advantages of favorable thermostability and favorable electrochemical performance. The addition reaction is carried out by regulating the composition of the ionic liquid and the proportion of ionic liquid to polymers and adding a right amount of plasticizer; or the conducting salts and the polymer materials containing amido functional groups are compounded to directly prepare the gel-state or all-solid-state polymer electrolyte with favorable performance. The polymer electrolyte has wide application prospects in the fields of chemical energy sources and especially new electrochemical energy storage systems aiming at high power, high energy density and high security requirement.

Description

technical field [0001] The invention belongs to the technical field of electrolyte materials, and is mainly oriented to high-power, high-energy-density power batteries, lithium-ion batteries, electrochemical supercapacitors, lithium-sulfur batteries and other high-energy batteries and applications in the technical fields of electronic equipment. technical background [0002] Ordinary ionic compounds are solid at room temperature due to strong ionic bonds, and have high melting point, boiling point and hardness. The introduction of large and asymmetric anions and cations will destroy the original ordered crystal structure due to steric hindrance, and the interaction between ions will be reduced to form salts that are liquid at room temperature, that is, room temperature molten salts (ionic liquids, Ionic liquids). Ionic liquids are liquids composed entirely of ions, and are liquid salts at low temperatures (<100°C), generally composed of organic cations and inorganic anion...

AI Technical Summary

Problems solved by technology

[0003] The liquid electrolyte widely used at present has the advantage of high conductivity, but because it contains flammable and volatile organic solvents, it releases flammable gases during charging and discharging, especially under certain unconventional working conditions (such as high power Charge and discharge, overcharge and overdischarge, etc.) to generate a lot of heat will accelerate the generation of gas, resulting in increased internal pressure of the battery, gas and liquid leakage, and even fire and explosion, so there is a serious safety hazard

At the same time, the liquid electrolyte system also has disadvantages such as poor thermal stability and high freezing point. The conductivity drops sharply at low temperature, and the electrolyte is easy to decompose and deteriorate at high temperature.

These problems have seriously restricted the development of new batteries and capacitors, especially high-power performance.

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