CALORIMETRIC MEASUREMENTS ON ELECTROCHEMICAL-CELLS WITH PD-D CATHODES

Two series of experiments were performed to determine the conditions of cell operation that produce sufficient excess heat to be useful for the production of energy. In the first series, the results from a differential temperature analysis of identical light- and heavy-water electrochemical cells were too ambiguous and, thus, not suitable for evaluating excess heat effects. In the second series, two Pd-D/LiOD-saturated D2O/Pt cells were operated at current densities between 12.5-500 mA/cm2 in a constant-heat-loss-rate twin calorimeter for 460 hours. Water loss measurements during the experiments indicated that the recombination reaction (2D2 + O2 --> 2D2O) did not occur. The D/Pd ratio was determined gravimetrically during the experiments. No excess heat was found within the sensitivity (0.13 W, 0.082 W/cm3 of Pd, 0.013 W/cm2 of Pd) and precision (+/-0.3 W) of the calorimeter.