The blended paste is applied to the copper foil - coating process
In this process, the paste that has been stirred after the previous process is evenly applied to the top and bottom of the 4,000-meter-long copper foil at a speed of 80 meters per minute. The copper foil before coating is only six microns thick, which can be described as "as thin as silkworm wings".
Coating is very important. It is necessary to ensure that the thickness and weight of the pole piece are consistent, otherwise it will affect the consistency of the battery. Coating must also ensure that there are no particles, debris, dust, etc. mixed with the pole. Otherwise, the battery will discharge too quickly, and security risks may arise.
Press the anode material on the copper foil and then cut it - cold pressing and pre-cutting
In the rolling workshop, the pole sheet attached with positive and negative electrode materials is rolled by roller. On the one hand, the coated material is tighter, the energy density is improved, and the consistency of thickness is ensured. On the other hand, dust and humidity are further controlled.
The cold-pressed electrodes were cut to the size needed to produce the cells, and the burr (visible only under a microscope) was sufficiently controlled to avoid puncturing the diaphragm and creating a serious safety hazard.
