Negative electrode sheet and secondary battery containing it

Abstract

The invention relates to a negative pole piece and a secondary battery containing it. Specifically, the present invention provides a negative electrode sheet, including a negative electrode current collector and a negative electrode film layer coated on at least one surface of the negative electrode current collector, the negative electrode film layer includes a negative electrode active material, characterized in that: The negative electrode active material includes graphite material, and the negative electrode sheet satisfies: 4×L×V OI ‑1 / 4×Dn10≤25, where L is the thickness of the single-sided negative electrode film layer on the negative electrode current collector in millimeters; Dn10 represents the particle size corresponding to 10% of the number distribution of negative electrode active material particles in microns; V OI Indicates the orientation index of the negative electrode film layer. The negative electrode sheet can make the secondary battery containing it have the characteristics of high energy density, fast charging, long cycle life and the like.

Description

technical field [0001] The invention belongs to the technical field of electrochemistry, and more specifically, the invention relates to a negative electrode sheet for a secondary battery and related secondary batteries. Background technique [0002] New energy vehicles represent the development direction of the world's automobile industry. As a new high-voltage, high-energy-density rechargeable battery, lithium-ion secondary batteries have outstanding features such as light weight, high energy density, no pollution, no memory effect, and long service life, so they are widely used in new energy vehicles. [0003] However, long charging time is one of the important factors limiting the rapid popularization of new energy vehicles. From the perspective of technical principles, the negative electrode has a great influence on the fast charging performance of the battery. At present, the fast charging batteries developed in the industry are mainly based on lithium titanate and am...

AI Technical Summary

Problems solved by technology

[0003] However, long charging time is one of the important factors limiting the rapid popularization of new energy vehicles

From the perspective of technical principles, the negative electrode has a great influence on the fast charging performance of the battery. At present, the fast charging batteries developed in the industry are mainly based on lithium titanate and amorphous carbon. Although the rate performance is good, these two negative electrodes are selected. The energy density of material batteries is low and cannot meet customer needs

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