A kind of lithium battery negative pole and its preparation method and lithium battery

Abstract

The invention discloses a lithium battery negative electrode, a preparation method thereof, and a lithium battery. The lithium battery negative electrode includes a current collector, an adhesive layer, a carbon nanotube film, an intermediate layer, and a lithium conducting layer. The current collector is coated with an adhesive layer, the adhesive layer is a network structure formed by coating the adhesive in a "well" shape, the carbon nanotube film is bonded to the current collector through the adhesive layer, the carbon nanotube film is provided with an intermediate layer, and the intermediate layer is provided with There is a lithium conducting layer, and the middle layer is a graphene film. The present invention can prevent a large amount of adhesive from being mixed into the carbon nanotube film while ensuring that the carbon nanotube film is closely bonded to the current collector and the graphene film, and the surface microporous structure of the carbon nanotube film and the graphene film can be fully utilized to improve The charge and discharge rate of the lithium battery is improved. At the same time, the microporous structure and large specific surface area of ​​the carbon nanotube film improve the liquid absorption and liquid retention capacity of the negative electrode, thereby improving the charge and discharge performance and cycle performance of the lithium battery.

Description

technical field [0001] The invention belongs to the technical field of lithium batteries, and in particular relates to a lithium battery negative electrode, a preparation method thereof, and a lithium battery. Background technique [0002] Lithium battery is a kind of green and clean energy. Compared with traditional nickel-chromium batteries and nickel-hydrogen batteries, it has the advantages of high voltage and high energy density. Many neighborhoods have developed rapidly, and lithium batteries have been widely used in rapidly developing portable devices. [0003] Traditional lithium batteries mainly include four parts: positive electrode, negative electrode, diaphragm and electrolyte. Common lithium-ion battery positive electrode materials are lithium-containing active compounds, and negative electrode materials are first made of carbon-based materials. When charging, the potential applied to the two poles of the battery will be The active compound of the positive elec...

AI Technical Summary

Problems solved by technology

[0003] Traditional lithium batteries mainly include four parts: positive electrode, negative electrode, diaphragm and electrolyte. Common lithium-ion battery positive electrode materials are lithium-containing active compounds, and negative electrode materials are first made of carbon-based materials. When charging, the potential applied to the two poles of the battery will be The active compound of the positive electrode releases lithium ions and embeds in the carbon in which the negative electrode molecules are arranged in a sheet structure. When discharging, the lithium ions are precipitated from the carbon again and recombined with the positive electrode compound, thereby achieving the effect of cycle charge and discharge. In lithium batteries During the first charging and discharging process, the electrode material and the electrolyte will react on the solid-liquid phase interface to form a layer of SEI film. The SEI film can isolate electrons, but it is an excellent conductor of lithium ions. The formation of the SEI film will consume part of the lithium. Ions, which increase the irreversible capacity of the first charge and discharge, reduce the charge and discharge efficiency of the motor material, but at the same time, the SEI film can avoid the co-embedding of solvent molecules and cause damage to the electrode material, thereby improving the cycle performance and service life of the motor. Decomposition occurs, and lithium ions are consumed during repair, which affects the charge and discharge efficiency of the battery. Therefore, how to improve the relationship between the charge and discharge efficiency of lithium ion batteries, battery cycle performance, and service life is the key to improving the overall performance of lithium batteries. , in order to solve this problem, the present invention provides the following technical solutions

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