This nuclear pacemaker was manufactured ca. 1972 by Dr. Orestes Fiandra’s CCC del Uruguay. It was powered by a McDonell-Douglas Betacel 400 which had promethium-147 sandwiched between semiconductor wafers. As the radioactive promethium isotope decays, it emits β-particles (electrons). The impact of the β-particles on a p-n junction causes a forward bias in the semiconductor similar to what happens in a photovoltaic cell (a solar cell).
The Betacel 400 had an open-circuit voltage of 4.7V and a short circuit current of 115μA. The maximum power output was 370μW. CCC’s pacemaker was expected to last for 10 years when powered by this nuclear battery. Continue reading