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Advanced thermoelectric microdevices integrated into thermal management packages and low power, electrical power source systems are of interest for a variety of space and terrestrial applications. By making use of macroscopic film technology, microgenerators operating across relatively small temperature differences can be conceptualized for a variety of high heat flux or low heat flux heat source configurations. The miniaturization of state-of-the-art thermoelectric module technology based on Bi2Te3 alloys is limited due to mechanical and manufacturing constraints for thermoelement dimensions (100-200μm thick minimum) and number (100-200 legs maximum). We are developing novel thermoelectric microdevices combining high thermal conductivity substrate materials such as diamond or even silicon, thin film metallization and patterning technology, and electrochemical deposition of 10-50μm thick thermoelectric films.

Lithium-ion rechargeable batteries have been demonstrated to have high energy density, high voltage, and excellent cycle life which make this technology more attractive than competing systems such as Ni-Cd and Ni-H2. However, the SOA cells fail to meet certain requirements necessary for various future NASA missions, such as good low temperature performance. Under a program sponsored by the Mars Exploration Program we have developed an organic non-aqueous electrolyte which has been demonstrated to result in improved low temperature performance of lithium-ion cells. The electrolyte formulation which has resulted in excellent low temperature performance, as well as good cycle life performance at both ambient and low temperatures, consists of a 1.0M solution of a lithium salt, lithium hexafluoro-phosphate (LiPF6), dissolved in a mixture of carbonates: ethylene carbonate + dimethyl carbonate + diethyl carbonate (1:1:1).