A first battery block has a first cut-away part on a side surface facing a second battery block. The second battery block has a second cut-away part on a side surface facing the first cut-away part such that the second cut-away part faces the first cut-away part. A battery module is provided with a space surrounded by the side surface on which the first battery block has the first cut-away part, the side surface on which the second battery block has the second cut-away part, and an inner side surface of the battery case.