To adjust the temperature of a storage battery under use efficiently, without using the power of the storage battery or the external power.

A thermoelectric conversion element A1 for power generation, generating power used for temperature control of a storage battery 2 by utilizing the temperature difference ΔT between the temperature T_PCS of a power conditioning system 3 and the outside air temperature T_R, is installed in the through hole 6a of a heat insulation layer 6 for power conditioning system so as to close the through hole 6a, thus intercepting the power conditioning system 3 from the outside air. Power being supplied from the thermoelectric conversion element A1 for power generation is guaranteed by ensuring the temperature difference ΔT between the temperature of the power conditioning system 3 and the outside air temperature, and temperature adjustment of the storage battery 2 is carried out accurately by using this power.