Composite current collector and preparation method thereof

Abstract

The invention relates to a preparation method of a composite current collector, and belongs to the field of batteries. The preparation method comprises the following steps: 1) pretreating a current collector, to be more specific, first removing oil in the current collector respectively with ethanol, acetone and deionized water in an ultrasonic cleaning device, and drying the current collector forlater use; 2) coating carbon slurry, to be more specific, first configuring a MOF solution, then placing the current collector in the step 1) in a solution, and drying after the reaction for standby use; 3) drying and carbonizing, to be more specific, placing the dried current collector in the step 2) in a protective atmosphere and carbonizing at a high temperature to obtain the current collectorwith a coating layer on the surface; 4) pickling, to be more specific, pickling the current collector in the step 3) to remove a non-carbon material on the surface of the current collector to obtain the current collector containing a carbon coating layer; and 5) drying and grinding, to be more specific, drying and grinding the obtained current collector to obtain the composite current collector. Ametal frame compound is carbonized, the carbonized metal frame compound is used as the coating layer of the current collector, adhesion between the coating layer and a substrate body is strong, the coating layer is not easy to fall off, and an obtained battery has good cycle performance.

Description

technical field [0001] The invention belongs to the field of batteries, and in particular relates to a composite current collector and a preparation method thereof. Background technique [0002] The technical scheme of the pole piece used in the existing lithium-ion power battery is to directly use a current collector with a thickness of 9-20 μm, and coat the active material to make the pole piece. Its shortcoming is that the surface roughness of ordinary current collectors is low and the specific surface area is small. After coating the negative electrode slurry, the adhesion between the light foil and the slurry will be relatively poor, which will cause the pole piece to be cut in the subsequent cutting process. Partial or even large-area material drop is prone to occur in the process of , punching, and transfer, which reduces the pass rate of the product and increases the cost. On the other hand, if the contact resistance between the current collector and the active mate...

AI Technical Summary

Problems solved by technology

Its shortcoming is that the surface roughness of ordinary current collectors is low and the specific surface area is small. After coating the negative electrode slurry, the adhesion between the light foil and the slurry will be relatively poor, which will cause the pole piece to be cut in the subsequent cutting process. Partial or even large-area material drop is prone to occur in the process of , punching and transferring, which reduces the pass rate of the product and increases the cost

This carbon film has limited ability to reduce contact resistance; therefore, it is necessary to study a new composite current collector

Images