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Experimental Lithium-ion (Li-ion) cells were constructed with three different types of Li-ion cathode materials and two different graphitic anodes. The cathode materials were lithium nickel cobalt aluminum oxide, LiNiXCoYAlZO2 (NCA), lithium nickel cobalt manganese oxide, LiNiXCoYMnZO2 (NCM), and lithium iron phosphate, LiFePO4 (FEP). The two graphitic anodes differed only in particle size. The cells were built in lots identified by their cathode and anode materials. The goal was to develop a battery for Naval Aviation applications. Initial testing favored the cells built with an NCM cathode. Further testing was per MIL-PRF-8565/14(AS) with Amendment 1, which resulted in a reduced voltage range during testing favoring the NCA lots. The cells were tested under two different types of cycle life conditions. In both cases, the NCA lots fared best. The NCA lots also had the lowest DC Resistance (DC Res) results (both ≤10 mΩ).

In a collaborative effort, Lithion and NASA/JPL developed a lithium ion battery capable of meeting the physical and electrochemical requirements for the 2003/2004 Mars Exploration Rover (MER) missions. The cells provide up to 145 Wh/kg, while the specific energy at the battery level, including wiring harnesses, thermal hardware and mounting hardware is approximately 90 Wh/kg. This paper discusses the specific requirements of the mission and how those requirements were met. Furthermore, an overview of the technique used to select cells for batteries is presented. The cell selection criteria resulted in cell to cell variation of approximately ± 0.6% in the first qualification unit.