Large-capacity lithium ion battery cathode and preparation method thereof

Abstract

The invention belongs to the technical field of electrochemistry, and specifically relates to a cathode used in an all-solid-state film lithium ion battery, and a preparation method thereof. The cathode comprises a battery substrate, and a cathode film on the surface of the substrate. The cathode film on the surface of the substrate is a cobalt phosphate film. The preparation method comprises steps that: a, metal cobalt powder and amorphous phosphorus powder are mixed according to a molar ratio of 1:1-3; the materials are well mixed and grinded; and the mixture is pressed into a target used in pulsed laser deposition; b, the target and the substrate are placed in a vacuum deposition chamber, wherein a distance between the two is 25 to 50mm, a working gas is an argon atmosphere, and the temperature of the substrate is 500 to 700 DEG C; c, laser beams from a laser are focused through a lens and conducted onto the rotary target; and particles exited by the laser beams is sputtered onto the substrate. According to the invention, the cobalt phosphate film has good electrochemical property and good chemical stability. As a cathode film of a high-performance lithium ion battery, the film provides good charge / discharge circulation reversibility. The preparation method is simple and material saving.

Description

technical field [0001] The invention belongs to the technical field of electrochemistry, and in particular relates to a lithium ion battery, in particular to a negative electrode for an all-solid thin film lithium ion battery and a preparation method thereof. Background technique [0002] Lithium-ion batteries are important power sources for laptop computers, cameras, cell phones, and other communications equipment, and have the potential to be used in cars and other vehicles as green energy. Existing lithium-ion batteries are mainly composed of carbon-based negative electrode materials, organic liquid electrolytes and lithium-containing transition metal oxide cathode materials. Among them, the all-solid-state thin-film lithium-ion battery has become the most ideal energy source due to its high safety and long cycle life. However, the commonly used negative electrode films such as lithium alloys, due to the strong volume change during intercalation and extraction of lithium...

AI Technical Summary

Problems solved by technology

However, the commonly used negative electrode films such as lithium alloys, due to the strong volume change during intercalation and extraction of lithium, lead to the destruction of the material structure, which causes deformation of the electrode, resulting in a decrease in the stability of the electrochemical cycle.

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