A kind of manufacture method of graphite negative plate

Abstract

The invention discloses a method for manufacturing a graphite negative plate, which comprises the steps of 1) pulverizing petroleum coke, 2) using petroleum coke particles, high-temperature asphalt adhesive and stearic acid mixture, 3) multi-stage temperature coating and bonding, 4) cooling to normal temperature, 5) adding Fe 2 o 3 Graphitization treatment, 6) Nano-Fe coated 3 o 4 Ionic liquid and magnetization treatment, 7) drying to obtain the finished product. This method can not only increase the degree of graphitization and greatly reduce the graphitization temperature of various amorphous carbons, but also improve the first charge and discharge efficiency and cycle stability of graphite anode materials, and the surface is coated with magnetic nanoparticles Fe3O4 and magnetized treatment, greatly reducing the pole piece OI value.

Description

technical field [0001] The invention relates to the field of manufacturing graphite, a negative electrode material of a lithium ion battery, in particular to a method for manufacturing a graphite negative electrode sheet. Background technique [0002] At present, the main anode materials for lithium-ion batteries are as follows: graphitized carbon materials, nitrides, silicon-based materials, tin-based materials, and new alloys. There are only two types of lithium-ion battery anodes that are commercialized on a large scale, which is graphite. Carbon-like materials and lithium titanate (LTO). [0003] Graphite material has good electrical conductivity, high crystallinity, and good layered structure, which is suitable for lithium intercalation-deintercalation. The discharge specific capacity can reach more than 300mAh / g, the charge-discharge efficiency is above 90%, and the irreversible capacity is less than 50mAh / g. g. Focusing on the future, the development focus of negati...

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Problems solved by technology

[0006] 3. The existing negative electrode sheets of lithium-ion batteries cannot arrange graphite end faces, so the only way to reduce the OI value (D002 / D110) of the negative electrode sheet is through secondary particle granulation. During the process, the OI value increases again, so that lithium ions cannot be well transmitted in the graphite of the negative electrode sheet

The nano-growth method can well grow the active material on the surface of the negative electrode substrate, but the method is complex and costly, difficult to control, and difficult to apply on an industrial micron scale

The negative electrode slurry is easy to introduce other metal ion impurities in the process of mixing and filtering, and it is difficult to remove them in the subsequent process, which will affect the charge and discharge and cycle performance of the battery cell.

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