The invention relates to a heat dissipation device with a closed-loop heat-pipe effect, comprising a biphasic loop, consisting of: an evaporator (1) for vapourising a heat-transfer fluid; a condenser (2) for liquefying the heat-transfer fluid; a vapour supply line (31) between the evaporator and the condenser, said vapour supply line being arranged downstream of the evaporator and upstream of the condenser so as to allow the passage of the vapour heat-transfer fluid from the evaporator to the condenser; and a liquid supply line (32) between the condenser and the evaporator, said liquid supply line being arranged downstream of the condenser and upstream of the evaporator so as to allow the passage of the liquid heat-transfer fluid from the condenser to the evaporator. The invention is characterised in that the device also comprises a tank (4) connected between the vapour supply line and the liquid supply line, said tank comprising an adsorbent material for the adsorption/desorption of the heat transfer fluid.