Battery electrode, preparation method thereof, and all-solid-state battery

Abstract

The invention relates to the field of all-solid-state batteries, in particular to battery electrodes, a preparation method thereof and all-solid-state batteries. The battery electrode comprises an electrode current collector and an electrode material layer attached to the surface thereof, wherein the electrode material layer comprises a polymer matrix and an electrode active material, and the polymer matrix is a nanoparticle modified crosslinked copolymer. The battery electrode and the electrolyte layer provided by the invention have higher ionic conductivity and mechanical strength, so that the battery has better specific capacity, cycle life and the like.

Description

technical field [0001] The invention relates to the field of all-solid-state batteries, in particular to a battery electrode, a preparation method thereof, and an all-solid-state battery. Background technique [0002] At present, most lithium-ion batteries on the market use liquid electrolyte as the conductive substance, but during use, the liquid electrolyte is volatile, flammable and explosive, causing many safety problems; moreover, it is easy to grow lithium dendrites, which limits the Application of lithium as negative electrode in batteries. Therefore, solid polymer electrolytes (SPEs) have been proposed to replace liquid electrolytes. The solid polymer electrolyte membrane not only plays the role of ion conduction, but also prevents the contact of positive and negative electrodes. And because of its strong plasticity, it can be made into films of different shapes according to different needs. It has good flexibility, can withstand the pressure of electrodes during c...

AI Technical Summary

Problems solved by technology

[0003] CN105680091A discloses a high-performance all-solid-state lithium-ion battery and its preparation method. In this application, the polymer electrolyte modified by lithium superionic conductor runs through the whole all-solid-state lithium-ion battery system, which improves the transmission rate of lithium ions and improves The rate charge and discharge capacity of all solid-state lithium-ion batteries; however, this method has the following major disadvantages: ①The negative electrode sheet preparation process is complicated, and the lithium powder has high environmental requirements; ②The negative electrode needs to mix lithium powder with superionic conductors and polymers , it is difficult to mix evenly, resulting in poor uniformity of the pole piece and poor battery consistency; ③The positive and negative pole pieces need to be soaked in the polymer electrolyte to make the battery. After soaking, the gel polymer electrolyte is bonded to the pole piece, increasing The complexity of the lamination process and the difficulty of correct lamination; ④The ionic conductivity of the polymer electrolyte is low, which is far from the requirements of commercial applications.

However, this method also has the following major disadvantages: ①The preparation process is complicated and there are many steps; ②The ionic conductivity of the polymer PUA and PMMA itself is not high, and the ionic conductivity of the polymer electrolyte membrane is mainly increased by adding ionic liquids. conductivity, and the high cost of ionic liquids is not suitable for industrial production; ③ dibenzoyl peroxide, the initiator used in ultraviolet crosslinking, is extremely unstable, and may cause fire and explosion when exposed to bright light, high temperature and reducing agents. Dangerous, so the risk is higher during operation

Images