Multiple-year battery based on highly efficient and stable dual-site radioactive isotope dye-sensitized betavoltaic cell

There is an unmet need for a battery that can provide full power for several decades for applications powering implants, remote applications, and satellites. We develop a novel betavoltaic device, a dual-site radioactive isotope dye-sensitized betavoltaic cell (d-DSBC), which is powered by the decay energy of the radioactive isotope of carbon. This device treats both the anode and cathode with a β-radiation source (dual-site source) to achieve a betavoltaic design with improved β-radiation absorption. The anode is composed of a TiO₂ layer first coated with radioactive isotope of citric acid, and then a ruthenium complex dye that acts as a charge generating layer. The cathode consists of a radioactive isotope of carbon nanoparticles/quantum dots. The d-DSBC exhibits a high power density per radioactive source of 20.75 nW cm⁻² mCi⁻¹, and an energy conversion efficiency of 2.86 %. These results represent a considerable step towards the practical application of betavoltaic cells.