Effect of nuclear radiation on the electrical properties of chemical double layer capacitors

The effects of nuclear radiation on the electrical properties of chemical double-layer capacitors are determined. The capacitors were irradiated in a 2-MW nuclear reactor to different fluence levels. The exposure rate was 2.2×10¹⁰ n/cm²-s for thermal neutrons, 9.52×10⁸ n/cm²-s for fast neutrons (>3 MeV), and 1.47×10⁶ rad/h for gamma radiation. The properties measured during and after irradiation included the capacitance, equivalent series resistance, and open-circuit voltage. The postirradiation effect on the leakage current was also determined. It was found that, while the capacitance increased during irradiation, the equivalent series resistance and the open-circuit voltage decreased slightly during irradiation. Changes in these properties, however, were not permanent, as was evident from postirradiation measurements. The leakage current did not show any significant change with radiation. The results indicate that chemical double-layer capacitors can be suitably used as a backup power source in electronic equipment operating in a radiation environment with total fluences up to 4.05×10¹⁴ n/cm²