A battery module includes a plurality of battery cells each of which includes two electrodes and which are arranged such that two electrode groups formed of the electrodes arranged in a row are formed and are electrically connected in series or in parallel by physically and electrically connecting an electrical connection member to each of the two adjacent electrodes in the electrode group; a separator disposed at least between the adjacent battery cells to achieve insulation of the battery cells; and a restraint band holding a state in which the battery cell and the separator are alternately stacked. The separator includes a lid covering the electrical connection member connected to the electrode and the electrode as a connection target of the electrical connection member from a side opposite to the battery cell.