A laminate battery comprising: a flat electrode assembly having a main face and a side face having a smaller area than the main face; and a laminate casing having a cup portion that is capable of housing therein the electrode assembly. The laminate casing is sealed with the electrode assembly housed in the cup portion and has a reduced pressure interior. The cup portion includes a base portion that covers the main face of the electrode assembly, a side portion that extends along the side face of the electrode assembly, and a bend portion that extends from the base portion beyond the side face of the electrode assembly, forms a bend towards the side face of the electrode assembly, and connects with the side portion. An angle of a vertex of the bend is within a range of 40° to 85° inclusive.