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The benefits of lithium battery systems lie within their high energy density (Wh/L) and high specific energy (Wh/kg). Manganese dioxide (MnO2) is an attractive active cathode material because of its high energy density and low material cost. Manganese dioxide is an intercalating compound for lithium that functions by solvating and desolvating lithium cations from the electrolyte in solid state. The lithium cations are deposited into the vacancies of the MnO2 cathode crystal structure. The objective of this effort focuses on the limited cycle life of rechargeable lithium manganese-based electrochemical systems, most importantly capacity fading of the cathode. These two characteristics are considered the major technology hurdles in rechargeable lithium battery technology.1, 2, 3, 4

This paper summarizes a series of papers investigating the, in use, behavior of lithium-ion cells and packs. Initial efforts concentrated on cell data 1, 2, 3 and 4 and were reported in 2003 through 2006. Follow-on efforts concentrated on battery pack data 5, 6 and 7 and were reported in 2007 through 2008. In these efforts lithium-ion cells and batteries (4P4S, 2P4S and 4S) were cycled at various conditions. Battery packs, fully augmented with control and monitoring electronics, were subjected to an external heat source at varying intensities which were applied to the base of the battery during both charge and discharge. This heat source effectively heated one cell of the battery string.

Power deficiencies have developed and presently continue to exist in numerous remote applications thus limiting mission effectiveness. The warfighter, first responder, personnel stationed in remote locations, shelters, and command posts have been burdened with exhaustive amounts of electronics. The demand for power has increased beyond the capability of supply and re-supply. The only viable solution to this problem is to equip the user with advanced battery technology, specifically high energy lithium-ion batteries, designed for this application. This paper will discuss the development of a man portable auxiliary power unit designed specifically to address these issues.