How about the dry pulping process used in lithium ion battery production? What are the steps?

In the production of lithium-ion batteries, electrode manufacturing, electric core assembly packaging, and Battery pre-charged into action are the three main stages of work, that is, the predecessor process, middle process, and back process mentioned in the lithium electric population. Electrode manufacturing is the production of lithium batteries flesh, the core assembly package is to shape the skeleton of lithium batteries, lithium batteries pre-charged into activation is to cast its soul, the three are closely dependent and indivisible, in the lithium-ion battery production process All play an important role. Anyone of these factors, such as raw materials, battery design, manufacturing equipment and processes, and the environment, may cause poor performance of battery products.

Lithium battery slurry is divided into a positive and negative slurry. The living substances, conductive agents, binders, solvents, etc. used in the two types of slurry vary with the battery system. The preparation of positive and negative plasma materials includes a series of process processes such as mixing, dissolving, and dispersing between liquids and liquids, liquids and solid materials, and in this process, it is accompanied by changes in temperature, viscosity, and environment.

The technological process of dry pulping is first to pre-Mix powder materials such as living materials and conductive agents at a certain speed. After the mixture is finished, the binder is added, mixed and stirred, the solvent is gradually added for mixing and dispersion, and finally, a certain amount of solvent is added for dilution and adjustment to the viscosity required for the coating. In the dry pulping process, the mixing and dispersion process of lithium-ion battery slurry can be divided into macroscopic mixing process and microscopic dispersion process. These two processes are always accompanied by the entire process of preparation of lithium-ion battery slurry. The dry pulping process can be represented by the following image:

1 Dry powder mixed. In the dry powder mixing stage, the material particles are contacted in the form of dots, dots, and dots, depending on the type of material, the contact forms are also different. At this stage, the internal porosity of the material is high, and the surface friction of the powder body is small. In a short period of time, the mixed contact of most materials can be achieved.

2 Material wetting mixed stage. At this stage, after the dry powder is mixed evenly, a binder liquid or solvent is added, and the raw material is wet and muddy. After the strong stirring of the blender, the material is cut and rubbed by mechanical force. At the same time, there will be internal friction between the particles. Under each force, the raw material particles tend to be highly dispersed. This stage has an important influence on the granularity and viscosity of the finished slurry.

3 dilution and dispersion stage. After the second stage is completed, the solvent is slowly added to adjust the viscosity and solid content of the slurry for further dispersion. At this stage, dispersion and reunion coexist and finally reach stability, and the slurry forms a stable suspension state. At this stage, the dispersion of materials is mainly affected by mechanical forces, friction resistance between powder fluids, high-speed dispersion shear forces, and the interaction force between slurry and container walls.

The difference between the dry pulping process and the wet process is that there is large internal friction between the materials in the second stage and between the equipment and the materials. Under various forces, the materials can achieve a good state of dispersion. The dispersion of the slurry is high, which is beneficial to the quality of the electrode. Under the same solid content, the viscosity of the slurry prepared by the dry method is low, and the lower the viscosity of the slurry, the shorter the time to maintain stability and the easier it is to stratify. In the process of coating, the slurry is easily settled in the corner and corner, causing the settlement to cause the coating accuracy fluctuations.

Secondly, the optimum state of the material in the dry pulping process is difficult to control. With the changes in the particle size, pH value, specific surface area, and other factors, the solid content in the optimal state will change and the process adjustment will need to be re-adjusted. Will affect the production efficiency and consistency between different batches of polar tablets. In order to ensure the quality of the electrode, and the slurry will not be stored for a long time, a better dispersed dry pulp process can be used.

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