A device sensitive to a heat flow or to a temperature gradient with at least one thermoelectric cell comprising essentially at least two continuous thin layers of a first conducting material having a face thereof coated with a thinner electrolytic deposit of a second conducting material different from said first conducting material and having thermoelectric properties different from the thermoelectric properties of said first conducting material, a heat conducting piece connecting said deposit of one of said two thin layers with said deposit on the other of said two thin layers, and at least a pair of layers of an insulating material disposed on opposite faces of said at least one thin layer and said deposit, the heat flow or temperature gradient being applied across a first one of said pair of layers, one of said thin layers, said deposit thereon, said heat conducting piece, said deposit on the other thin layer, said other thin layer and a second one of said pair of layers when said device is in operation, and said piece having a dissymmetrical shape or being displaced relative to the deposit on each one of said two thin layers.