Lithium battery composite electrode pole piece and preparation method and application thereof

Abstract

The invention provides a lithium battery composite electrode pole piece with high rate capability and high cycle performance, and belongs to the technical field of secondary ion lithium batteries. Theinvention provides a positive electrode pole piece or a negative electrode pole piece of a lithium battery. The positive electrode pole piece or the negative electrode pole piece comprises a currentcollector and functional slurry coated on the surface of the current collector, wherein the functional slurry is obtained by uniformly mixing a positive electrode active material or a negative electrode active material, a conductive agent and a polymer solution, and a polymer in the polymer solution is degradable bio-based polyester. The composite electrode obtained by the invention can realize anefficient and uniform electron transmission network and ion transmission channel, and effective coating and protection of active particles, thereby having excellent cycle performance and rate capability.

Description

technical field [0001] The invention provides a lithium battery composite electrode pole piece with high rate performance and high cycle performance, and belongs to the technical field of secondary ion lithium batteries. Background technique [0002] High energy density, high power density, and long cycle life make secondary ion batteries (such as Li-ion, Na-ion batteries) the most attractive energy storage devices for industry and academia. The development of advanced energy storage technologies not only depends on the development of high-capacity active materials (such as high-nickel ternary cathode materials), but also largely depends on the effective adjustment of electrode microstructure and interface, as well as the surface protection of active materials. Electrode microstructures and interfaces are key factors governing the ion / electron transport network, and thus, their design regulation is crucial to the improvement of battery performance. A small amount of polymer...

AI Technical Summary

Problems solved by technology

[0004] 2) From the perspective of electrochemical reactivity, traditional polymer additives are inactive components, which are reflected in the hindrance to ion and electron transport

[0005] 3) With the development of high-capacity active materials, people hope to build functional coatings on their surfaces to protect electrode particles, thereby greatly extending their service life; these requirements cannot be met by existing commonly used polymer additives

[0007] 5) From the perspective of nano-coating technology on the surface of active materials, the existing inorganic nano-coatings, such as metal oxides, phosphates, fluorides, etc., have high costs, complex production processes, brittle quality, and difficulty in achieving uniform and continuous coating Therefore, the development of new multifunctional active particle nano-coatings (polymer artificial SEI films or CEI films) has become one of the core tasks in the development of next-generation high-performance batteries.

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