Cylindrical Cell Heat-Shrink Insulation for Tab-to-Casing Isolation

The patent changes the physical state of the insulating material from a rigid pressed-down tape to a heat-shrinkable film that can be thermally contracted. By applying heat treatment, the film transitions from a loose state to a tightly adhered smooth state, eliminating wrinkles while maintaining insulation reliability. This parameter change (thermal state) resolves the contradiction between achieving smooth contact and avoiding deformation.

The patent replaces the mechanical pressing method with a thermal shrinking method. Instead of using mechanical force to press the insulating tape onto the tab (which creates wrinkles), the invention uses heat to cause the film to shrink and conform naturally to the tab surface, creating a smooth wrinkle-free insulation layer that maintains reliable electrical isolation.

The patent replaces the mechanically pressed insulating tape with a thermally shrunk film. The thermal shrinking process creates a permanent molecular-level adhesion to the tab surface, forming a stable wrinkle-free insulation layer. This thermal bonding mechanism provides superior long-term stability compared to mechanical pressing, preventing the warping and insulation failure that occurs over time with traditional tape methods.

The patent applies a thermal parameter change (heating) to transform the insulating material from a flexible state to a stabilized shrunk state. This thermal processing permanently sets the film in a wrinkle-free configuration that maintains its shape and insulation properties over time, resolving the stability issue with traditional pressed tape that deforms during battery operation and storage.