In-situ composite solid electrolyte, application thereof, all-solid-state battery and preparation method thereof

Abstract

The invention provides a preparation method for an all-solid-state battery. The method comprises the steps of S1, mixing lithium salt, additive and initiator to obtain mixed solution, wherein the additive is micromolecule monomer comprising unsaturated bond; and S2, carrying out in-situ polymerization and adhesion by the solution in a cathode layer, a solid electrolyte layer and an anode layer andamong the layers, thereby obtaining composite solid electrolyte, wherein a solid electrolyte layer comprises inorganic solid electrolyte and adhesive. Compared with the prior art, the method has theadvantages that through utilization of flowability of the micromolecule monomer additive comprising the unsaturated bond, solid particles are wetted sufficiently, ion transport channels are constructed through in-situ polymerization and solidification, electrode layers are adhered once, and a battery is moulded; the compatibility of the solid-solid interface in the all-solid-state battery can be effectively improved; and the preparation method is simple and fast, is compatible with the existing battery technology and is beneficial for large-scale preparation.

Description

technical field [0001] The invention belongs to the technical field of lithium ion batteries, and in particular relates to an in-situ composite solid electrolyte and its application, an all-solid battery and a preparation method thereof. Background technique [0002] In recent years, the rapidly developing electric vehicle and energy storage industries have put forward higher requirements on the energy density, cost, cycle and safety of secondary batteries represented by lithium-ion batteries. Traditional liquid electrolytes have safety problems such as leakage, fire, and explosion, which seriously hinder the further development of lithium-ion batteries. The all-solid-state lithium battery, which replaces the organic liquid electrolyte with a solid electrolyte, is expected to fundamentally solve the safety problem of the battery, and at the same time improve the energy density of the battery, so it has become a research hotspot. [0003] In recent years, the research on sol...

AI Technical Summary

Problems solved by technology

First of all, since the solid electrolyte does not have the wetting effect of the liquid, the solid particles in the positive electrode layer, the electrolyte layer and the negative electrode layer of the solid battery are in point contact, and the gaps between the particles can easily cause the ion transmission channel in the battery system to be blocked.

Secondly, when all-solid-state battery pole pieces are stacked and formed, the joining of each electrode layer (positive electrode layer / solid electrolyte layer; solid electrolyte layer / negative electrode layer) is also a major difficulty. At present, most of them are sintered or pressed, and the interlayer interface is rigid. Contact, not conducive to process scale-up preparation