Abstract: Disclosed are a separator membrane, a separator membrane roll, a battery cell, and a power lithium battery. The separator membrane includes a porous base film and a bonding layer; in a preset direction of the porous base film, the surface of the porous substrate includes a middle blank area, and a coated area at the two ends; the bonding layer is applied on the two coated areas. By means of applying the bonding layer to both ends of the porous base film surface, it is possible, during the process of assembling and forming the lithium battery cell, to cause the bonding layer to contact and bond with the two ends of the negative electrode inside the lithium battery cell, effectively ensuring that the lithium battery bears sufficient tension, pressure, and vibration during assembly, vibration testing, and long-term cycling.