Pulp for lithium ionic cell electrode and manufacturing method thereof

Abstract

A sizing material for electrodes of a lithium ion battery mainly comprises an active material, a conductive agent, an adhesive and a solvent, and is characterized in that the distribution ratio of the active material, the conductive agent, the adhesive and the solvent is 100 : 0-4 : 1-7 : 35-100. The preparation process thereof comprises the following steps: 1) mixing the adhesive with partial solvent to prepare a glue body with the viscosity of 1 to 10 percent; 2) mixing the conductive agent weighed according to the distribution ratio with the glue body prepared in the step 1) and stirring to form a conductive glue; 3) mixing the active material and the rest solvent weighed according to the distribution ratio with the conductive glue and stirring to form a premixed sizing material; 4) introducing the premixed sizing material into a dispersion machine rotating at a high speed to conduct dispersion; 5) cooling and vacuumizing the dispersed sizing material to form the sizing material for the electrodes of the lithium ion battery. The sizing material has the better use performance, and the preparation method thereof solves the defect in the traditional mixture that the layering of the conductive agent is easily caused by a larger density difference when the conductive agent is mixed with the active material and the like, thereby ensuring the uniform distribution of each ingredient of the sizing material.

Description

【Technical field】 [0001] The invention relates to the field of manufacturing lithium ion batteries, in particular to a slurry for lithium ion battery electrodes and a preparation method for the slurry. 【Background technique】 [0002] Lithium-ion batteries will be the preferred power source for mobile electronic products for a long period of time due to their advantages such as high volume specific energy, long service life, environmental protection, high voltage and high safety. It is formed by sealing a positive electrode group, a negative electrode group, a diaphragm for conducting ions and blocking electrons, and a non-aqueous electrolyte in a casing. The positive and negative electrode groups are respectively made of positive and negative electrode active materials, conductive agents, binders and solvents, etc., which are homogenized into a uniform slurry, uniformly coated and / or filled on the collector, dried and rolled. When the battery is charging, lithium ions are e...

AI Technical Summary

Problems solved by technology

[0009] However, the above process has the following problems in the actual preparation process: 1) It is easy to cause the dry material to splash when the powder is mixed. On the one hand, it will cause environmental pollution and affect the health of the operator. On the other hand, the actual slurry formula will deviate from the design. 2) In the homogenization step, although the slurry can be temporarily uniformed, because it does not separate the agglomerated material particles in the slurry, it will be stored for a period of time. Finally, the slurry will appear delamination phenomenon, that is, the stability of the slurry is not good; 3) The slurry preparation time is long and the efficiency is not high

The above defects will affect the quality of lithium-ion battery products

[0010] In addition, in the patent documents published by the Chinese Patent Office, there are some methods of changing the distribution ratio of the components of the slurry or adding other additives to achieve better uniformity, such as increasing the proportion of the binder, or adding a certain amount of slurry at the same time. A small amount of dispersant, etc., so that the agglomerated material particles can be well separated when the slurry is mixed, but this method reduces the content of the main components of the slurry, and also increases the production cost of the slurry

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