| 摘要 |
PURPOSE: A secondary battery prevents the loss of insulating resistance, protects the welding part of a tab and a lead against external impact, and improves impact resistance. CONSTITUTION: A secondary battery includes an electrode current collector (10) including a positive electrode, a negative electrode, and a separator; a pouch case (20) surrounding the electrode assembly; and a heat-shrinkable protection film (13) covering the welding part of an electrode lead (12) and an electrode tab. The heat-shrinkable protection film is a heat-shrinkable PET film. The heat-shrinkable PET film has a thickness of 20±5 um. The welding part is fastened by tension generated when the PET film is heated to 60-70°C and shrunk and is steadily fixed. |
