Polymer solid electrolyte and preparation method and application thereof

Abstract

The invention provides a polymer solid electrolyte and a preparation method and application thereof. The preparation method comprises the steps of firstly, dissolving rubber in an organic solvent to prepare a solution A; secondly, mixing and initiating lithium salt, a plasticizer, a photoinitiator, an oligomer of acrylate and a derivative thereof and a small molecular additive to prepare a solution B, and forming a polymer solid electrolyte with high ionic conductivity, good flowability and positive and negative electrode interface compatibility; and performing thermal-induced cross-linking blending on the solution B and the solution A, grafting a polymer in the solution B into rubber, coating the surface of a base membrane with the polymer, and performing hot press molding to obtain thepolymer solid electrolyte. When the polymer solid electrolyte is used for a lithium ion battery, the polymer solid electrolyte has the characteristics of large lithium ion transference number, capability of inhibiting growth of lithium dendrites, stable structure, high conductivity, high cycling stability and the like.

Description

technical field [0001] The invention belongs to the technical field of lithium batteries, and in particular relates to a polymer solid electrolyte, a preparation method thereof and an application in lithium ion batteries. Background technique [0002] Since solid-state electrolytes can fundamentally solve the safety problems of current commercial lithium batteries, solid-state lithium batteries have become a research hotspot in recent years. Common solid electrolytes are divided into polymer solid electrolytes and inorganic solid electrolytes. Polymer solid electrolyte has the advantages of good thermal stability, high stability to lithium, good cycle performance, and can be prepared into flexible thin film batteries; but low ionic conductivity, poor electrode wettability, low working power, The development and application of polymer solid-state lithium batteries are limited. Inorganic solid electrolytes have high ionic conductivity, wide electrochemical window, and good s...

AI Technical Summary

Problems solved by technology

Polymer solid electrolyte has the advantages of good thermal stability, high stability to lithium, good cycle performance, and can be prepared into flexible thin film batteries; but low ionic conductivity, poor electrode wettability, low working power, The development and application of polymer solid-state lithium batteries are limited

Inorganic solid electrolytes have high ionic conductivity, wide electrochemical window, and good stability have attracted widespread attention. However, inorganic solid electrolytes are not easy to prepare, have poor interface contact, poor mechanical properties, and are sensitive to water and oxygen. application

[0003] At present, polymer solid-state electrolytes are the most promising solid-state electrolytes for practical production, mainly because polymer solid-state electrolytes have good processability, and the main bottleneck problem is the low ion conductivity, which hinders their practical application.

In addition, due to the poor mechanical properties of polymer electrolytes, it is easy to cause lithium dendrites to puncture the electrolyte membrane and cause a short circuit, resulting in inability to cycle for a long time. Therefore, there are two major problems in the practicality of polymer electrolytes that need to be solved urgently. One is the ionic conductivity. Lower, second, poor mechanical properties

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