Tritium-Charged Capacitor

Calculations and measurements are presented for direct capacitor charging from tritiated electrodes, efficiency in converting beta decay energy into electric current, the effect of geometry on charging current, and the dielectric engineering options/trade-offs. Experiments using 1.4 × 10¹² Bq (38 Ci) of tritium provided a 148-nA short circuit (charging) current at 5300 V of open circuit voltage, giving 160-W peak electrical power, with 12.5% overall efficiency. Calculations are in good agreement with the measured voltage accumulated over time for the tritium capacitor.