Large excess heat production in Ni-H systems

In a previous paper [1] some of us reported on the existence of an anomalous heat production observed in hydrogen-loaded nickel rods. The phenomenon occurs when a cell containing a nickel rod is maintained at temperatures above a critical value and is filled with gaseous H2 at subatmospheric pressures. A constant input power was used to raise and keep the cell temperature constant at its working value (corresponding to about 700 K for the Ni rod). It was possible to induce an increase of the sample temperature from its working value to about 820 K. This anomalous equilibrium condition will be referred in the following as excited state. The system was able to remain in the excited state for several months. The experimental cell described in ref. [1] was successively modified and also a new cell was built with an improvement which allows the measurement and the monitoring of the external surface temperature. With this new set-up, the external temperature increase, together with the internal one, have been utilized to characterize the excited state of the Ni sample. The existence of an exothermic effect, whose heat yield is well above that of any known chemical reaction, has been unambiguously confirmed by evaluating the thermal flux coming from the cells. An important feature of our systems is that they can remain in the excited state for a long time. This characteristic allowed us to search for ionizing radiation coming from the cells. Very clear evidence of neutrons and -rays has been reported by us [2-4]. Systematic studies of such processes and their correlation with heat production are in progress.