METHOD FOR COOLING BATTERY

In a laminated all-solid-state battery, a negative electrode terminal and a positive electrode terminal around which a resin sheet is wound are sandwiched between exterior members (laminate films), and the exterior members are joined by heat welding. The laminated all-solid-state battery is in contact with the heat exchanger via a heat conductive sheet. When the terminal temperature detected by the temperature sensor provided at the negative electrode terminal and the positive electrode terminal is equal to or higher than a predetermined value, the flow rate control valve is fully closed and the flow rate control valve is fully opened. The cooling amount of the joint portion in which the negative electrode terminal and the positive electrode terminal extend increases, the temperature of the joint portion decreases, the deformation of the resin sheet is suppressed, and the unsealing of the seal is suppressed.