Manufacturing method of battery

A manufacturing method of a battery, the manufacturing method comprising performing roller conveying, by a conveying roller, of a bipolar electrode laminate that is an elongated sheet and that is heated, wherein

• the bipolar electrode laminate includes a first electrode active material layer, a current collector layer, and a second electrode active material layer, in this order,
• the first electrode active material layer is made up of a plurality of island portions extending in a conveying direction, with at least one gap portion extending in the conveying direction among the island portions,
• a temperature decrease of the bipolar electrode laminate when the bipolar electrode laminate passes over the conveying roller is no less than 30° C.,
• the manufacturing method further comprising pressing the bipolar electrode laminate with a pressing roller prior to the bipolar electrode laminate passing over the conveying roller,
• a temperature decrease of the bipolar electrode laminate when the bipolar electrode laminate passes over the pressing roller is less than 30° C., and
• the pressing roller includes a protruding portion at a position overlapping with the gap portion or an opposite side face from the gap portion, such that stretching stress in a lateral direction is applied to the gap portion when the bipolar electrode laminate passes over the pressing roller.