SiC基辐射伏特电池研制及性能优化

Background : Betavoltaic nuclear batteries, leveraging beta-emitting radioisotopes, offer inherent advantages such as long-term reliability, high energy density, compact form factors, and robust resistance to interference, positioning them as promising power sources for self-powered portable or embedded microdevices. Purpose : In order to enhance the conversion efficiency and output power of betavoltaic batteries, we comprehensively considered the effects of backscattering, depletion region width, diffusion length, and electrode structure on charge collection efficiency, conversion efficiency, and output power. Methods : By optimizing the device and electrode structure, we successfully fabricated ⁶³Ni-SiC-based PIN junction betavoltaic batteries with higher overall conversion efficiency and output power, employing Monte Carlo simulations and numerical computations. Results : The fabricated batteries exhibited short-circuit currents, open-circuit voltages, output powers, and total conversion efficiencies ranging from 10.29 to 13.43 nA/cm², 1.32 to 1.44 V, 11.66 to 14.69 nW/cm², and 2.24% to 2.82%, respectively. Compared with our teams previous work, the open-circuit voltage, fill factor, and overall conversion efficiency increased by an average of 127.50%, 114.47%, and 512.10%, respectively. Moreover, the overall conversion efficiency was higher than those reported in the literature (0.5% to 1.99%). Conclusions : These results indicate that by introducing a PIN structure with concentration gradient I- layer, optimizing the depletion region width and doping concentration, and optimizing electrode materials and increasing the spacing between electrode grid lines, the conversion efficiency and output power of betavoltaic batteries can be significantly improved, providing important theoretical guidance and experimental evidence for the design and fabrication of betavoltaic batteries.