To provide a battery module with high volumetric efficiency. A battery module (200) comprising stacked and connected unit cells (30) each comprising a power generation element (10), a cathode terminal (31), and an anode terminal (32) disposed on the opposite side of the cathode terminal of the power generation element, wherein a connection laminate layer (20) including a resin layer (21), a metal layer (22) and a resin layer (21) in this sequence, is disposed between the unit cells, and wherein the metal layer of the connection laminate layer is electrically connected to the cathode terminal of one adjacent unit cell and the anode terminal of the other unit cell.