JOINING METHOD, JOINING STRUCTURE, AND BATTERY

A joining method includes providing an electrode body that includes electrode plate end portions overlapping each other in a thickness-wise direction of the electrode plate end portions; providing a current collector including a folded portion, the folded portion includes two opposing holding walls that hold the electrode plate end portions of the electrode body in between, and a top portion that connects the two holding walls and includes an opening; and welding the electrode plate end portions to end surfaces of the two holding walls that define the opening by irradiating an edge of the electrode plate end portions with a laser beam in a state in which the edge of the electrode plate end portions held between the two holding walls projects into the opening.