A lithium battery negative electrode sheet, its preparation method and application, and lithium-ion secondary batteries

Abstract

This invention discloses a lithium battery negative electrode sheet, its preparation method and application, and a lithium-ion secondary battery, belonging to the field of lithium battery technology. The lithium battery negative electrode sheet includes a negative electrode current collector and a negative electrode active material layer disposed on at least one surface of the negative electrode current collector; the lithium battery negative electrode sheet satisfies: 30 ≤ (K S ×θ×S×10 15 ) / W≤45; W is the areal density of the negative electrode sheet, θ is the porosity of the negative electrode sheet, S is the specific surface area of ​​the negative electrode active material, K S K is the powder diffusion coefficient of the negative electrode sheet. This is achieved by adjusting K... S By understanding the relationship between S, W, and θ, and ensuring that it satisfies the above formula, even negative electrode active materials with average chemical properties can significantly improve the performance of lithium-ion batteries. This allows the parameters of the negative electrode active materials to reach optimal matching during the charging process, thereby improving the fast charging performance, high-temperature storage performance, and safety performance of lithium-ion batteries. The improvement in battery cycle life is particularly significant.

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