Novel Nuclear Batteries Based on Radioluminescence

A new type of nuclear battery, based on the sandwich structure of solar cells and tritium gas‐filled radioluminescent glass tubes (RLGTs), is developed and used successfully as a low‐power source. The radioluminescence (RL) is produced by bombarding beta particles, emitted by tritium gas, on ZnS: Cu is coated on the inner cylindrical surface of a glass tube. The response of solar cells to the optical spectrum of RL is studied and corelated with the current–voltage characteristics of the nuclear battery. The results show that the short‐circuit current, maximum output power, and energy conversion efficiency are enhanced but nonlinearly, with the increase in the number of RLGTs and by mounting the sandwich structure on an aluminum or plastic holder which acts as light reflector. Three such nuclear batteries are developed using different types of solar cells and their electrical performance is studied. Use of the developed nuclear battery as a low direct current power source is demonstrated by operating a digital watch and a light‐emitting diode for long periods.