OBJECTIVE: Develop and demonstrate an electric power management system that will couple low power photovoltaic (PV) energy generating devices with a Li-ion battery with at least 96% module efficiency. DESCRIPTION: Renewable energy, specifically photovoltaic, is an attractive technology for man-portable power sources and tactical applications. However, to be effective as a system, it is necessary to have a power manager that can efficiently couple a small solar array (~20W) to a battery such as the BB2590. Power managers are already being fielded with PV sources, but their usefulness has been limited by the design of the power manager. The goal of this topic is to develop a cost-effective, lightweight power manager that displays high efficiencies for low power modules in a user-friendly format that can rapidly charge a BB2590. In addition, given the nature of Li-ion batteries, maximum use of solar input is achieved when multiple batteries are charged in parallel, so a power manager is sought that can charge multiple batteries simultaneously. Other capabilities that will benefit the system are scavenge mode, buck/ boost capability, high-speed maximum point tracking, reduced heat and IR signature, a wide operating temperature range, charging capability in low light (<0.1W input power), and near loss-less power transfer. PHASE I: Produce a design for a power manager that can charge multiple BB2590 batteries in parallel demonstrating greater than 96% power transfer efficiency, battery loss of less than 8% for 1 year of standby, weighing less than 235g and costing less than $600. PHASE II: Fabricate and test the power manager designed in Phase I. Measure and validate performance across various load profiles and generation regimes, including scavenge mode. Incorporate additional capabilities, including buck/boost capability, networking capability, and maximum point tracking. PHASE III: Develop prototype production line for the power manager and commercialization plans using the knowledge gained during Phases I and II. PRIVATE SECTOR COMMERCIAL POTENTIAL: Cost effective, efficient, power managers have many applications working with commercial photovoltaic and energy-scavenging systems.