A battery module includes a plurality of cells and a plurality of holders. The plurality of cells are parallelly arranged in a row at intervals. The plurality of cells have explosion-proof valves which are provided therein and which are capable of opening upon an increase in an inner pressure in the plurality of cells. The plurality of holders are arranged among the cells so as to hold the cells. The holders have holder pieces which are integrally formed therein and which cover at least part of the explosion-valves so as to prevent emissions from the explosion-proof valves from being released in all directions.