Battery unit temperature management device

A battery unit temperature management device comprising:

• a battery unit that is capable of being charged and discharged;
• a heater that operates due to electricity supply from the battery unit and heats a heat exchange medium that exchanges heat with the battery unit;
• a changing structure that changes a heat transfer capacity between the battery unit and the heat exchange medium;
• and
• a controller that controls heating of the heat exchange medium by the heater and a change of the heat transfer capacity by the changing structure,
• wherein the controller makes the heat transfer capacity when a temperature of the heat exchange medium does not reach a first temperature that is equivalent to a temperature of the battery unit while the heat exchange medium is heated by the heater smaller than the heat transfer capacity when the temperature of the heat exchange medium has reached the first temperature while the heat exchange medium is heated by the heater,
• the battery unit includes a plurality of battery cells disposed side by side,
• the changing structure includes a heat transfer material disposed between adjacent battery cells of the plurality of battery cells, the heat transfer material exchanging heat with the heat exchange medium, and an area changing structure that changes the heat transfer capacity between the battery cells and the heat exchange medium by changing contact areas between the heat transfer material and the adjacent battery cells, and
• the heat transfer material is in a corrugated plate shape, and changes in shape from the corrugated plate shape to a flat plate shape when receiving an external force in a direction in which the battery cells are arranged.