The paper describes a micronuclear battery that utilizes the conversion of beta particles into photons and back into electrons through a photoelectric cell to potentially deliver a nuclear battery of higher efficiency than other nuclear battery concepts and with much greater energy per gram and lifetime than chemical batteries. The Monte Carlo nuclear code MCNP has been used to analyze the performance of the proposed battery, and the photoelectric stage has been shown to be insensitive to the expected radiation for at least 1 yr of performance.