Method for producing flexible package lithium ion battery negative plates

Abstract

The invention belongs to the technical field of lithium ion batteries, and in particular relates to a method for producing flexible package lithium ion battery negative plates, wherein the method comprises the steps that: adding a carbon material, a polyvinylidene fluoride adhesive agent and a conductive agent into the solvent, mixing uniformly, and coating cathode slurry on the negative current collector so as to form anode diaphragms; placing the negative plates to be baked in a vacuum oven to bake, wherein the temperature of the oven is higher than the final melting temperature of polyvinylidene fluoride, so as to melt polyvinylidene fluoride adhesive agent completely into liquid; and cooling the negative plates to be cooled so as to complete the production of the negative plates. Compared with the prior art, the method causes crystle transformation of polyvinylidene fluoride, so that a monoclinal TGTG' molecular chain configuration is transferred into an orthogonal TTTT molecular chain configuration with high remanent polarization and higher bonding strength; and the bonding performance is improved, and thus enhancing the cycle performance of batteries, reducing the cyclic swelling of batteries, and improving the rate capability of batteries simultaneously.

Description

technical field [0001] The invention belongs to the technical field of lithium-ion batteries, and in particular relates to a method for manufacturing a negative electrode sheet of a soft-packed lithium-ion battery. Background technique [0002] Lithium-ion battery is an electrochemical energy storage device, which is mainly composed of several parts such as positive electrode, negative electrode, separator and electrolyte. insert) material. [0003] At present, flexible packaging lithium-ion batteries have become the first choice for consumer electronics products. However, during the use of such batteries by consumers, the problem of sharp decrease in battery power and gradual increase in battery thickness (that is, large cycle expansion) often occurs. If these problems are not solved, the service life of electronic products will be reduced, and consumers will need to replace batteries frequently, resulting in a decrease in consumer satisfaction, thereby affecting consumer ...

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Problems solved by technology

[0006] The purpose of the present invention is to provide a method for manufacturing a negative electrode sheet of a soft-packed lithium-ion battery in view of the deficiencies in the prior art, and the negative electrode sheet of a soft-packed lithium-ion battery produced by this method has the characteristics of high adhesion and high environmental friendliness , so that the cycle life of the soft-packaged lithium-ion battery comprising the negative electrode sheet made by the method is significantly improved, and the rebound after the battery cycle and the rebound of the pole piece are also greatly reduced, so as to overcome the cycle life of the soft-packaged lithium-ion battery in the prior art Short and big loop swell deficiencies

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