Integrated electrode, integrated solid-state battery module, solid-state battery and preparation method thereof

Abstract

The invention discloses a preparation method of a solid-state battery, which comprises the following steps: mixing a positive active material, a solid electrolyte, a binder, a conductive agent and a first solvent, and intermittently coating a positive current collector with the mixture to obtain a positive electrode; adding the solid electrolyte into a second solvent to obtain a solid electrolyte filling liquid; mixing a binder, a solid electrolyte and a third solvent to obtain solid electrolyte slurry; mixing a negative electrode active material, a solid electrolyte, a binder, a conductive agent and a fourth solvent to obtain negative electrode slurry; and coating or curtain coating on the positive electrode according to a lamination sequence of the solid electrolyte filling liquid, the solid electrolyte slurry and the negative electrode slurry, and drying to obtain the integrated electrode. The invention also discloses an integrated electrode, an integrated solid-state battery module and a solid-state battery. The electrode plate is filled with the solid electrolyte, and the integrated module is prepared, so that the interface impedance is reduced, the ion transmission capability of the electrode is improved, the procedures of electrode plate preparation and cell assembly are simplified, and the cost is reduced.

Description

technical field [0001] The invention belongs to the technical field of solid-state batteries, and in particular relates to an integrated electrode, an integrated solid-state battery module, a solid-state battery and a preparation method thereof. Background technique [0002] With the popularization of electric vehicles, various manufacturers continue to improve the high energy density of batteries to increase the driving range of vehicles. At the same time, battery safety issues have become increasingly prominent and have attracted widespread attention. Solid-state batteries replace the electrolyte with solid-state electrolytes, which solves the risks of battery combustion, explosion, and liquid leakage. At the same time, metal lithium can be applied to lithium batteries, which have the advantages of high safety and high energy density. The entire industry regards solid-state batteries as the next generation One of the important technical routes of batteries has also increas...

AI Technical Summary

Problems solved by technology

Such a solution leads to a clear interface and a relatively large interface impedance.

At the same time, the preparation of solid electrolyte film also increases the process, and there is a high degree of difficulty

In addition to the interface problem between the positive and negative electrodes and the solid electrolyte layer, due to the lack of electrolyte infiltration, the gaps between the positive electrode particles cannot conduct lithium ions, and there are also interface problems.

[0004] Chinese patent CN108574119A discloses a method for preparing a solid-state battery, which adopts synchronous coating of one electrode and an electrolyte layer, and then assembles with the other electrode, but there is still an interface problem, and it is difficult to ensure the integrity of each part after winding by winding. Pressure equalization and tight bonding between layers

[0005] Chinese patent CN111786015A discloses a method for preparing a positive electrode and a solid-state battery. The solid electrolyte layer is coated on the positive electrode, and when assembled with the prepared negative electrode, there is still an interface problem. At the same time, the prepared positive electrode base layer is still There is not much difference from the electrodes prepared by ordinary methods, but there are still many pores

[0006] Chinese patent CN108574119A discloses an all-solid-state battery electrode and its preparation method and application. It uses a solvent-soluble solid electrolyte and a solvent-insoluble solid electrolyte to mix and coat the electrode surface, but the dissolved solid electrolyte is evaporated after the solvent , the ionic conductivity of the obtained solid electrolyte will decrease to a certain extent, and the mixing of the two will affect the lithium ion conduction of the solid electrolyte layer. If the two are coated separately, the solid electrolyte layer will not be affected

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