NOVELTY - The fluid circuit passes through combustible battery (1) and first point (Pi) of circuit is situated at output and upstream of the battery (1). Besides fluid circuit the system includes an air conditioning circuit through which cooling fluid flows. The two circuits are thermally coupled, at heat exchanger connected to cooling fluid circuit, at the output of the battery (1), in a branch of the circuit mounted in parallel on a radiator (3) forming part of the circuit..    USE - For control of heat dissipation in a hybrid motor vehicle.    ADVANTAGE - Designed to reinforce the effectiveness of a classic automobile cooling circuit when the load on it is high as in the case where the vehicle is driven by electrical energy provided from a combustible battery operating under maximum load.    DETAILED DESCRIPTION - The second point (Pj) is in the cooling circuit at the exchanger output. Thermal management circuit for an automobile including at least a fluid circuit for heat transfer from various parts or vehicle volume so as to regulate their temperature. The system also includes a fluid reservoir (R). Means (C,V1,V3) to selectively connect at least an input of the reservoir to first (P1,P2) and second (P3) points of the fluid circuit having first (T1,T2) and second (T3) fluid temperature levels, respectively greater and less than the fluid temperature (TR) in the reservoir. Means (C',V4) to connect sensibly simultaneously to an output of the reservoir at a third point (P4) of the fluid circuit so as to control heat exchange between the circuit and the reservoir( R) according to the operating conditions of the vehicle, the fluid circuit being in its temperature regulation mode.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic of the vehicles cooling circuit in contact with various vehicle parts and the combustible battery    battery (1)    vehicle aero-therm heater (2)    principal radiator (3)    pump (4)    complementary radiator (6)    vehicle parts to be cooled (7)    reservoir (R)    temperature sampling points (P)    sampling point temperatures (T)    signals sent to computer. (S)