A holder for battery that maintains a temperature difference between battery modules below a specific value by the shape of a module support portion including receiving recesses divided into halves to become smaller from the upstream to the downstream of cooling air flow direction so that the contact area of the cooling air between the battery modules varies. The battery modules may include a module support portion supporting a plurality of battery modules and a plurality of receiving recesses formed at regular intervals on the module support portion, on which the battery modules are placed.