Commercial nickel Cadmium batteries for space use : A proven alternative for LEO satellite power storage

For the past 14 years, satellite engineers at Surrey have successfully applied commercially available Nickel Cadmium (NiCd) batteries to Low Earth Orbit (LEO) Microsatellite and Minisatellite programmes. Details of the commercial cell battery's flight heritage, as well as flight data taken from microsatellites in a variety of different orbital and thermal environments, will validate the success of SSTL's battery screening and matching techniques. In particular, one spacecraft's battery has performed some 70,000+ charge/discharge cycles over a 14 year period and is still providing a useful function. A carefully engineered commercial cell battery, screened rigorously and used within a controlled charge / discharge regime, is capable of providing a low cost, reliable product. With many spacecraft manufacturers taking a substantial interest in the smaller, faster, cheaper approach to spacecraft production, the evidence in this paper will make it difficult to justify the budget and schedule implications required for fully qualified aerospace batteries.