METHOD FOR MANUFACTURING BATTERY CELL

To prevent an electricity generation element from being affected by heat during manufacture of a battery cell, a method for manufacturing a battery cell includes: stacking electrode sheets in a layering direction to form an electricity generation element, the electrode sheets each including an electrode and a current collector, the electrodes being located in a container, the current collectors each being connected to the electrode in the container and protruding outward from an opening of the container; pressurizing and heating resin pieces from an outside toward a center in layering direction at positions of the openings of the container, the resin pieces being located between the adjacently stacked current collectors; promoting transfer of heat from the electricity generation element to an outside of the electricity generation element during pressurizing and heating the resin pieces; welding resin pieces together between the current collectors; and sealing the opening of the container.