The hot pressing and shaping process of battery cells is as follows: The wound or stacked battery cells are placed on the template, the pressure of the booster cylinder and the temperature of the template are set, and then the upper and lower templates are used to shape the battery cells under certain pressure and temperature conditions to achieve uniform battery cell thickness, reduce battery cell elasticity, reduce the core loading qualification rate and ensure the uniformity of the thickness of the finished battery cells.
Regarding square batteries, the hot-pressing shaping device uses upper and lower templates that are flat. Under pressure, the flat templates are closed to flatten the battery cells.
Regarding cylindrical batteries, the hot-pressing shaping device consists of two cylinders fixed to a base that move in opposite directions. At the ends of the piston rods of the two cylinders are two semi-circular molds with cylindrical grooves. The radii of the cylindrical grooves on the two semi-circular molds are equal and equal to or smaller than the preset core radius. A robotic arm or clamp holds the core at the center of the two semi-circular molds. The two cylinders are controlled to drive the two semi-circular molds to close and move in opposite directions, causing the two semi-circular molds to compress the core, thereby winding and shaping it to the preset size so that it can be placed into a matching housing.
Generally, during the hot pressing and shaping of battery cells, insulation withstand voltage tests are performed simultaneously to detect whether there are micro-short circuits inside the cell. If there are tiny metallic foreign particles inside the cell, the cell diaphragm will be punctured when the cell is pressed down, making it easy to detect defective products with micro-short circuits.
