Abstract: A liquid circulator includes a circulation passage, a pump, a cooler, and one or more processors. The circulation passage includes a supply path and a recovery path. The supply path supplies a discharge process liquid to a battery of a mobile body. The recovery path recovers the supplied discharge process liquid. The pump circulates the discharge process liquid in the circulation passage. The cooler cools the discharge process liquid flowing in the circulation passage. The one or more processors control the pump and the cooler to supply the discharge process liquid at a predetermined temperature to the battery.

Abstract: A mobile body includes a battery, a housing, and a closing member. The housing has a vent hole and accommodates the battery. The closing member closes the vent hole when a temperature of the closing member exceeds a predetermined temperature.

Abstract: A mobile object includes a battery, a coolant, and a discharger. The coolant in a solid state is disposed around the battery and is liquefied by heat transferred from the battery. The discharger discharges the coolant liquefied out of the mobile object.