COMPARATIVE ANALYSIS OF SATELLITE BATTERY TECHNOLOGIES

As satellite battery technologies evolve, cost analysts must reassess whether historical subsystem data remain valid for cost estimating relationships (CERs). This study examines whether nickel-cadmium (NiCd), nickel-hydrogen (NiH₂), and lithium-ion (Li-Ion) systems can be commingled for CER development. Using data from the Unmanned Space Vehicle Cost Model (USCM), we compare normalized costs and estimate regression models with and without chemistry-specific interaction terms. The results strongly support excluding NiCd, which exhibits statistically distinct cost behavior. For NiH₂ and Li-Ion, pooled regressions and coefficient stability tests suggest commingling is appropriate when estimating NiH2 based systems. However, interaction terms reveal significant differences in cost behavior between NiH2 and Li-Ion suggesting that comingling may be inappropriate when estimating Li-Ion based systems. We conclude that NiCd data should be excluded and recommend continued caution when commingling NiH₂ and Li-Ion, with periodic reassessment as more Li-Ion data become available.