Battery module, electric power unit, and work machine

A battery module is provided with: a cell assembly configured by sandwiching a plurality of battery cells with a pair of holding members; and a housing case that houses the cell assembly, the housing case having a vent hole for gas, and a flow path passing through the vent hole being formed in a labyrinth structure by covering the vent hole with a connecting portion of the pair of holding members. 电池模块具备：单体集合体，其通过由一对保持构件对多个电池单体进行夹持而构成；以及容纳壳体，其容纳所述单体集合体，所述容纳壳体具有气体的通气孔，通过由所述一对保持构件的连结部分将所述通气孔覆盖，从而将穿过所述通气孔的流路形成为迷宫结构。