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Under the Mars Surveyor Program (MSP01), lithium-ion batteries were developed by Lithion Inc. (Yardney Technical Products Inc.), each being 28 V, 25 Ah, 8-cells, 9 kg and fully qualified prior to mission cancellation. In addition to the requirement of being able to supply at least 90 cycles on the surface of Mars, the battery was demonstrated to be capable of operation (both charge and discharge) over a large temperature range (-20° to +40°C), with tolerance to non-operational excursions to -30° and +50°C. After mission cancellation, the batteries delivered to JPL were subjected to generic performance tests to demonstrate the applicability of the technology to meet future NASA aerospace applications. One of the two batteries currently being tested at JPL is undergoing testing according to anticipated performance requirements of future Mars Lander applications. The primary goal of this activity is to determine the performance capability to power surface operation on Mars for a prolonged period (> 3 years) after being subjected to a long cruise period. The second 25 AHr battery is being tested to determine the viability of using lithium-ion technology for future planetary orbiter applications. The test implemented consists of cycling the battery continuously under LEO conditions (30% DOD), while periodically checking the battery impedance and full capacity (100% DOD). Prior to initiating these tests, a number of characterization tests were performed to determine general performance attributes and battery health. In addition to presenting battery data, results obtained with individual cells will also be presented to further describe the capabilities of the technology to meet future applications. [ABSTRACT FROM PUBLISHER]

NASA requires lightweight rechargeable batteries for future missions to Mars and the outer planets that are capable of operating over a wide range of temperatures, with high specific energy and energy densities. Due to the attractive performance characteristics, lithium-ion batteries have been identified as the battery chemistry of choice for a number of future applications, including Mars rovers and landers. The Mars 2001 Lander (Mars Surveyor Program MSP 01) will be one of the first missions which will utilize lithium-ion technology. This application will require two lithium-ion batteries, each being 28 V (eight cells), 25 Ah and 8 kg. In addition to the requirement of being able to supply at least 200 cycles and 90 days of operation on the surface of Mars, the battery must be capable of operation (both charge and discharge) at temperatures as low as -20°C. To assess the viability of lithium-ion cells for these applications, a number of performance characterization tests have been performed, including: assessing the room temperature cycle life, low temperature cycle life (-20°C), rate capability as a function of temperature, pulse capability, self-discharge and storage characteristics, as well as mission profile capability. This paper describes the Mars 2001 Lander mission battery requirements and contains results of the cell testing conducted to-date in support of the mission, [ABSTRACT FROM PUBLISHER]