Design and analysis of nuclear battery driven by the external neutron source

•A new type of space nuclear power called NBDEx is investigated.•NBDEx with 252Cf has better performance than RTG with similar structure.•Its thermal power gets great improvement with increment of fuel enrichment.•The service life of NBDEx is about 2.96 year.•The launch abortion accident analysis fully demonstrates the advantage of NBDEx.

Based on the theory of ADS (Accelerator Driven Subcritical reactor), a new type of nuclear battery was investigated, which was composed of a subcritical fission module and an isotope neutron source, called NBDEx (Nuclear Battery Driven by External neutron source). According to the structure of GPHS-RTG (General Purpose Heat Source Radioisotope Thermoelectric Generator), the fuel cell model and fuel assembly model of NBDEx were set up, and then their performances were analyzed with MCNP code. From these results, it was found that the power and power density of NBDEx were almost six times higher than the RTG’s. For fully demonstrating the advantage of NBDEx, the analysis of its impact factors was performed with MCNP code, and its lifetime was also calculated using the Origen code. These results verified that NBDEx was more suitable for the space missions than RTG.