Abstract: Provided is a secondary battery, which includes a separator having excellent air permeability such that the separator is adhered to a positive electrode plate and/or a negative electrode plate at a low temperature under a low pressure and swelling in an electrolyte solution is relatively suppressed. The secondary battery includes an electrode assembly including a positive electrode plate, a negative electrode plate and a separator interposed between the positive electrode plate and the negative electrode plate, wherein the separator further includes an adhesive layer formed on its surface, the adhesive layer includes a binder, and a gel-sol transition temperature of the binder is in a range of 70° C. to 90° C.

Abstract: Provided is a secondary battery, which includes a separator having excellent air permeability such that the separator is adhered to a positive electrode plate and/or a negative electrode plate at a low temperature under a low pressure and swelling in an electrolyte solution is relatively suppressed. The secondary battery includes an electrode assembly including a positive electrode plate, a negative electrode plate and a separator interposed between the positive electrode plate and the negative electrode plate, wherein the separator further includes an adhesive layer formed on its surface, the adhesive layer includes a binder, and a gel-sol transition temperature of the binder is in a range of 70° C. to 90° C.