Current collector carbon coated aluminum foil and its preparation method

Abstract

The invention discloses a current collector carbon coated aluminum foil and its preparation method. A carbon-containing composite layer is arranged on the substrate of the current collector carbon coated aluminum foil, and is combined with the substrate through a binder, wherein the thickness of the carbon-containing composite layer is 1-100mum; the carbon-containing composite layer comprises granular conductive carbon black pre-dispersed by a dispersant, and fibrous conductive carbon; the granular conductive carbon black and the fibrous conductive carbon filled between the layers of the granular conductive carbon black form a netted node form conductive network. The composite layer is tightly combined with the substrate of the aluminum foil, so the conductivity and the corrosion resistance of the aluminum foil are improved, and the aluminum foil is protected from oxidation or chemical corrosion. The preparation method of the aluminum foil comprises the following operations: mixing the conductive carbon black with the dispersant in an organic solvent to pre-disperse, adding the fibrous conductive carbon, uniformly mixing, adding the binder to prepare a slurry, coating on the aluminum foil, and carrying out vacuum drying. The current collector carbon coated aluminum foil enables the interface impedances of the current collector and an active layer to be reduced, the internal resistance of a battery to be reduced, and the cycle life and the ratio performances of the battery to be improved when the aluminum foil is used as a lithium ion battery anode current collector. The aluminum foil has the advantages of simple technology, low cost and wide application prospect.

Description

technical field [0001] The invention belongs to the field of new energy, and in particular relates to a collector carbon-coated aluminum foil and a preparation method thereof, in particular to the preparation of a lithium ion battery and a collector used in supercapacitor electrodes. Background technique [0002] With the increasing shortage of traditional resources and energy and the increasingly serious environmental problems, sustainable development has become a new concept for the development of human society, and the development of new energy storage and conversion technologies has become the focus of energy strategies of various countries. Among the secondary power supply technologies, lithium-ion batteries have become the most promising technology in the new era due to their high energy density, high operating voltage, long cycle life, and low self-discharge. At present, the electrode current collector materials of lithium-ion batteries generally use metal copper foil...

AI Technical Summary

Problems solved by technology

There are also problems of high energy consumption and long process

[0006] The patent application by Ruan Dianbo et al. (CN1015923962A) discloses a method for preparing an activated carbon electrode by superimposing an aluminum foil substrate, a graphite conductive adhesive layer and an activated carbon coating layer and performing a rolling process. However, the graphite conductive adhesive layer and active The carbon coating layer uses adhesives, the bonding strength is limited, and it will increase the internal resistance of the pole piece, and the unity of low impedance and good adhesion cannot be obtained.

[0007] Among the means of modifying aluminum foil, the technologies listed above all have long processing procedures, high energy consumption, certain risks, and high costs. They cannot achieve the unity of bonding strength and low internal resistance, and it is difficult to achieve a large-scale promotional use

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