MANUFACTURING METHOD OF SECONDARY BATTERY

A method of manufacturing battery including an electrode assembly having a positive electrode, a negative electrode, and a separator arranged between the positive electrode and the negative electrode, and a battery case configured to accommodate the electrode assembly. The separator is provided with adhesion layers formed on both surfaces of the separator. The method comprising: an arranging step for arranging the electrode assembly, in which the positive electrode and the separator are adhered by the adhesion layer and the negative electrode and the separator are adhered by the adhesion layer, inside the battery case; a peeling step for peeling off at least one, among the positive electrode and the negative electrode, and the separator on the electrode assembly; and a liquid injection step for performing a liquid injection of an electrolyte solution into the battery case after the peeling step.