A temperature management system on a vehicle cooling circuit using a heat transfer liquid, the circuit comprising a path for circulating the heat transfer liquid and, arranged on the path: - in series, a means for circulating the heat transfer liquid along the path, an engine for moving the vehicle, whose components are to be placed in a heat exchange relationship with the heat transfer liquid, and a heat exchanger having an inlet and an outlet for said heat transfer liquid in order to place said heat transfer liquid in a heat exchange relationship with another fluid within the exchanger, - mounted on a first branch, between the inlet and the outlet of the heat exchanger, a heat store into which said heat transfer liquid can enter and from which it can exit, - and valves (14, 16, 18; 14', 16', 18', 20') positioned so that heat transfer liquid arriving from the engine flows toward the heat exchanger and/or the heat store, the heat store being a latent heat storage and thermal energy release unit containing at least one volume: -- enclosing elements made of phase change material for storing and releasing the thermal energy contained in said heat transfer liquid in view of a heat exchange with this heat transfer liquid, -- and around which is installed a thermal barrier comprising at least one first layer containing a phase change material and which is surrounded by one second layer containing a porous thermally insulating material to thermally isolate said volume from the outside, characterized in that said thermal barrier has no physical contact with the heat transfer liquid circulating within the elements made of phase change material, where at least part of the thickness of a peripheral wall separates them, and at least some of said elements made of phase change material have a melting temperature that is lower than or equal to the melting temperature of the phase-change material of said first layer. - in series, a means for circulating the heat transfer liquid along the path, an engine for moving the vehicle, whose components are to be placed in a heat exchange relationship with the heat transfer liquid, and a heat exchanger having an inlet and an outlet for said heat transfer liquid in order to place said heat transfer liquid in a heat exchange relationship with another fluid within the exchanger, - mounted on a first branch, between the inlet and the outlet of the heat exchanger, a heat store into which said heat transfer liquid can enter and from which it can exit, - and valves (14, 16, 18; 14', 16', 18', 20') positioned so that heat transfer liquid arriving from the engine flows toward the heat exchanger and/or the heat store, the heat store being a latent heat storage and thermal energy release unit containing at least one volume: -- enclosing elements made of phase change material for storing and releasing the thermal energy contained in said heat transfer liquid in view of a heat exchange with this heat transfer liquid, -- and around which is installed a thermal barrier comprising at least one first layer containing a phase change material and which is surrounded by one second layer containing a porous thermally insulating material to thermally isolate said volume from the outside, -- enclosing elements made of phase change material for storing and releasing the thermal energy contained in said heat transfer liquid in view of a heat exchange with this heat transfer liquid, -- and around which is installed a thermal barrier comprising at least one first layer containing a phase change material and which is surrounded by one second layer containing a porous thermally insulating material to thermally isolate said volume from the outside,