Theoretical Prediction of Diamond Betavoltaic Batteries Performance Using ⁶³ Ni

Abstract

A diamond p-n junction is used to convert the decay energy of 63 Ni source into electrical energy. The selfabsorption effect of the 63 Ni source, the backscatter process and the transport process of beta particles in diamond materials are studied. Then the theoretical maximum of electrical properties and the energy conversion efficiencies of diamond-63 Ni p-n junction batteries are achieved. Finally, a feasible design of 𝑝 + 𝑝 − 𝑛 + junction battery, which has the maximum output power density of 0.42 𝜇W/cm 2 and the optimal device conversion efficiency of 26.8%, is proposed.

Effect of americium‐241 source activity on total conversion efficiency of diamond alpha‐voltaic battery

“…The I sc of the alpha‐voltaic battery is given by where η CCE is the charge collection efficiency, P dep is the energy emitted from the source deposited in depleted region of the diode, and the E ehp is the average energy needed to create an electron‐hole pair in diamond.…”

“…where P max is the maximum output of the battery, P total is the total energy the device obtained from the source, equal to P source multiplied by the effective area of the device, and FF represents the fill factor. The I sc of the alpha-voltaic battery is given by 15,22…”

“…Bormashov et al reported large area diamond nuclear batteries with the highest total conversion of 3.6%. High power density beta‐ and alpha‐voltaic diamond batteries were fabricated by Bormashov et al and Langley et al Liu et al predicted the theoretical conversion efficiency of Ni 63/diamond nuclear batteries, and a total conversion efficiency of 8% and V oc of 4.8 V were predicted based on the diamond p‐n junction battery. Single‐crystal chemical vapor deposition (CVD) diamond membranes were used to fabricate beta‐voltaic cells, and an η total of 9.4% was predicted by the electron beam induced currents technique .…”

Review—Betavoltaic Cell: The Past, Present, and Future

“…Lu et al investigated the self-absorption effect of 63 Ni. 31 Similarly, the apparent power density of radioactive source reached the saturation value after an initial rise. Meanwhile, the selfabsorption loss reaches over 90% when the source is relative thick.…”

“…Currently, the depletion region of a practical battery is usually smaller than the main ionizing radiation region to reduce the phonons from recombination of photoexcited carriers. 31 Because the electron diffusion length is much larger than that of the hole under the same excess carriers concentration, the p-type doped region and n-type doped region are selected as the emitter layer and base layer, respectively, for efficiently utilizing the energy deposited outside the depletion region.…”