A method of manufacturing a non-aqueous electrolyte secondary battery that includes: an electrode body having a positive electrode, a negative electrode and a plurality of separators, an upper R portion of the electrode body being curved, the respective separators having surplus portions (23a,24a) that are in contact with neither the positive electrode nor the negative electrode at terminal ends of the respective separators (23,24); a case having an accommodation portion and a lid portion, the accommodation portion being a container that has an opening in an upper face of the container and accommodates the electrode body, and the lid portion being a member that closes up the opening in the upper face of the accommodation portion, the method characterized by comprising: forming positive electrode mixture layers on both faces of the positive electrode current collector of the positive electrode respectively; forming negative electrode mixture layers on both faces of the negative electrode current collector of the negative electrode respectively; arranging the negative electrode outside the positive electrode in the electrode body; winding the positive electrode, the negative electrode and the plurality of separators (23,24); performing an initial charging process in which the non-aqueous electrolyte secondary battery is charged while being bound such that the electrode body is pressed via the accommodation portion of the case, with the surplus portions (23a,24a) of the plurality of the separators (23,24) not located at the upper R portion of the electrode body; and performing a high-temperature aging process in which the non-aqueous electrolyte secondary battery that has been subjected to the initial charging process is maintained at a predetermined high temperature, wherein the predetermined high temperature in the high-temperature aging process is equal to or higher than 60 degrees Celsius. an electrode body having a positive electrode, a negative electrode and a plurality of separators, an upper R portion of the electrode body being curved, the respective separators having surplus portions (23a,24a) that are in contact with neither the positive electrode nor the negative electrode at terminal ends of the respective separators (23,24); a case having an accommodation portion and a lid portion, the accommodation portion being a container that has an opening in an upper face of the container and accommodates the electrode body, and the lid portion being a member that closes up the opening in the upper face of the accommodation portion, the method characterized by comprising: forming positive electrode mixture layers on both faces of the positive electrode current collector of the positive electrode respectively; forming negative electrode mixture layers on both faces of the negative electrode current collector of the negative electrode respectively; arranging the negative electrode outside the positive electrode in the electrode body; winding the positive electrode, the negative electrode and the plurality of separators (23,24); performing an initial charging process in which the non-aqueous electrolyte secondary battery is charged while being bound such that the electrode body is pressed via the accommodation portion of the case, with the surplus portions (23a,24a) of the plurality of the separators (23,24) not located at the upper R portion of the electrode body; and performing a high-temperature aging process in which the non-aqueous electrolyte secondary battery that has been subjected to the initial charging process is maintained at a predetermined high temperature, wherein the predetermined high temperature in the high-temperature aging process is equal to or higher than 60 degrees Celsius. forming positive electrode mixture layers on both faces of the positive electrode current collector of the positive electrode respectively; forming negative electrode mixture layers on both faces of the negative electrode current collector of the negative electrode respectively; arranging the negative electrode outside the positive electrode in the electrode body; winding the positive electrode, the negative electrode and the plurality of separators (23,24); performing an initial charging process in which the non-aqueous electrolyte secondary battery is charged while being bound such that the electrode body is pressed via the accommodation portion of the case, with the surplus portions (23a,24a) of the plurality of the separators (23,24) not located at the upper R portion of the electrode body; and performing a high-temperature aging process in which the non-aqueous electrolyte secondary battery that has been subjected to the initial charging process is maintained at a predetermined high temperature, wherein the predetermined high temperature in the high-temperature aging process is equal to or higher than 60 degrees Celsius.