Silicon-carbon anode paste and preparation method thereof

Abstract

The invention relates to a silicon-carbon anode paste and a preparation method thereof, and belongs to the technical field of lithium-ion batteries. The silicon-carbon anode paste comprises an acrylonitrile multi-component copolymerized LA-type water-based electrode binder, a carbon black Super-p conductive agent, a single-arm carbon nanotube suspension emulsion, a silicon-carbon / carbon nanotube composite anode material and deionized water. The preparation method of the anode paste comprises the following steps: (1) adding the acrylonitrile multi-component copolymerized LA-type water-based electrode binder and the deionized water to a planetary stirrer for stirring, preparing a binder solution and standing the binder solution for later use; (2) putting the carbon black Super-p conductive agent and the single-arm carbon nanotube suspension emulsion to the planetary stirrer for ball-milling and wet mixing; (3) putting the mixed two conductive agents and the silicon-carbon / carbon nanotube composite anode material into the planetary stirrer for carrying out thick material stirring; and (4) adding the binder solution for mixing and stirring, finally adding the deionized water to adjust the viscosity of the anode paste and sieving the paste.

Description

technical field [0001] The invention belongs to the technical field of lithium batteries, and in particular relates to a silicon-carbon negative electrode slurry and a preparation method thereof. Background technique [0002] Lithium-ion batteries have high energy density, long cycle life, good rate performance and safety performance, and are environmentally friendly, becoming a major energy product. With the rapid development of electronic technology, electronic and power products are becoming more and more miniaturized and lightweight, and the performance requirements of lithium-ion batteries are getting higher and higher, especially the requirements for energy density of lithium-ion batteries. Ion batteries are required to have higher energy density. People are constantly seeking and improving the specific capacity of the positive electrode while also continuously seeking and increasing the specific capacity of the negative electrode to increase the energy density of lit...

AI Technical Summary

Problems solved by technology

[0003] Graphite anode materials have been the most widely used due to their own advantages such as good cycle performance. However, graphite anode materials have a low lithium storage capacity, and the lithium intercalation potential is close to that of metal lithium. High-rate charging is difficult and there are safety hazards.

As a latecomer to lithium-ion battery anode materials, silicon-carbon composite anode materials have high lithium storage capacity, but relatively poor conductivity and cycle performance, mainly due to the volume effect of silicon-carbon materials under high-level deintercalation conditions, resulting in The shedding of materials and current collectors during charge and discharge affects the cycle performance of the battery, so a reasonable conductive agent, binder, and slurry preparation process are crucial to the cycle performance of silicon carbon anode materials

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