Analysis: Lithium battery working principle and assembly process

As we all know, the positive electrode material of a lithium ion battery is lithium cobalt oxide, and the negative electrode is carbon.

The working principle of lithium-ion battery refers to its charging and discharging principle. When the battery is charged, lithium ions are generated on the positive electrode of the battery, and the generated lithium ions move to the negative electrode through the electrolyte. The carbon as the negative electrode has a layered structure, and it has many micropores. The lithium ions reaching the negative electrode are embedded in the micropores of the carbon layer, and the more lithium ions are embedded, the higher the charging capacity.

By the same token, when the battery is discharged (ie, the process we use the battery), the lithium ions embedded in the carbon layer of the negative electrode come out and move back to the positive electrode. The more lithium ions return to the positive electrode, the higher the discharge capacity. What we usually call battery capacity refers to the discharge capacity.

It is not difficult to see that during the charging and discharging process of a lithium ion battery, lithium ions are in a state of motion from a positive electrode to a negative electrode to a positive electrode. If we compare the lithium-ion battery to a rocking chair, the two ends of the rocking chair are the two poles of the battery, and the lithium ion is like an excellent sportsman, running back and forth at both ends of the rocking chair. Therefore, the experts gave the lithium-ion battery a cute name rocking chair battery.

Lithium battery working principle and assembly process

Tools/raw materials

Cathode material

Anode material

Diaphragm paper

Step / method

Pulping:

The powdered positive and negative active materials are mixed with a special solvent and a binder, and stirred at a high speed to form a slurry of positive and negative materials.

Lithium battery working principle and assembly process

Coating film:

The prepared slurry was uniformly coated on the surface of the metal foil, and dried to prepare positive and negative electrode sheets, respectively.

Lithium battery working principle and assembly process

3 assembly:

According to the positive electrode sheet--separator--the negative electrode sheet--the separator is placed in the order from top to bottom, and the battery core is wound up, and then the process of injecting the electrolyte and sealing is completed, that is, the assembly process of the battery is completed. Into the finished battery.

4 Turn into:

Charge and discharge test the finished battery with a dedicated battery charge and discharge device, test each battery, and filter out qualified finished batteries to be shipped.

The page contains the contents of the machine translation.