Since Sony Company succeed in inventing lithium-ion battery in 1900, lithium-ion battery had
developed in an incredible speed because ofits high energy density, long circulation period and good electronic quality. Now, lithium-ion battery has been widely used in cell phones, laptops, cameras,video recorders, and other electronic products[l]. Lithium-ion battery is made of electrode,electrolyte, and lithium-ion battery separator. One of the important functions of lithium-ion battery separator is to separate the anode from cathode and prevent the electrons in battery, at the same time, allow ions to pass. This function makes it possible that lithium-ions transfer quickly between anode and cathode in the process of charging and releasing. The nonwovens produced by electrospinning are made of entanglement between the fibers, and the mechanical property of the separator will have an obvious improvement for nets structures forming between the fibers. Gao[2]gave the heat treatment to the electrospinning separator, the result showed that the separator heated had an obvious zoom in modulus, tensile strength, break elongation.