Thickness: 4.5–6 μm, tensile strength: 400–500 N/mm², elongation ≥ 7%. It delivers moderate tensile strength, high elongation, deformation resistance and rolling resistance with uniform double-side surface, capable of buffering volume expansion stress of anodes during charging and discharging. Specially designed for high-expansion anode systems such as silicon-carbon and silicon oxide, it applies to long-cycle power batteries for passenger vehicles and household energy storage batteries.