Composite graphite for lithium secondary battery and manufacturing method thereof

Abstract

The invention discloses composite graphite used for a lithium secondary battery and a production method thereof. The production method is as follows: spherical graphite is taken as a substrate, preheated by a heating mixing roll until the temperature of powder is between 55 and 85 DEG C, added with a clad material (a mixed liquid which consists of coal tar, maltha and liquid resin, and fully mixed; and the mixture is filled into a graphite container for macromolecular treatment, sent into a direct-fired cemented carbonized oven for carbonizing treatment, and subjected to screen stencil or airflow classification to obtain composite graphite powder. The production method simplifies the production procedure and saves the production cost; the product is taken as a cathode material of the lithium secondary battery, so that the lithium secondary battery has high initial charging and discharging efficiency and large discharge quantity.

Description

technical field [0001] The invention relates to a composite graphite for lithium secondary batteries and a manufacturing method thereof, in particular to a kind of simplification of the manufacturing process to save the production cost, obtain the negative electrode material of the lithium secondary battery, and the battery made by it can obtain higher discharge capacity and high discharge efficiency. Background technique [0002] With the rapid development and maturity of electronic technology, people have put forward new requirements for light-weight, high-energy, and adaptable power sources. The well-known lithium-ion battery has a large potential difference between the positive and negative materials, which can increase its power. Energy density achieves the characteristics of small size and high power, which can meet the needs of electronic products. [0003] The negative electrode materials of lithium-ion batteries are generally made of graphite. In terms of graphite,...

AI Technical Summary

Problems solved by technology

At the same time, when a single liquid resin is used as the coating material, due to the excessive pores on the carbon mesh layer after heat treatment, and when the heat treatment is carried out at 800-1200 ° C, the amorphous carbon on the surface will be fused and agglomerated. The coated carbon material is prone to peeling off during the disintegration process, resulting in an excessively large specific surface area and affecting the characteristics of the battery

In terms of heat treatment, if the temperature and time are insufficient, it is easy to cause the deformation of the battery material during the charge and discharge process to be inconsistent, resulting in the peeling phenomenon of the base material and the cladding material, which also makes the discharge capacity and charge and discharge efficiency of the battery low.

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