A contract was awarded to the Virginia Power Electronics Center to compare two battery discharger topologies for use on the Earth Observing System. The following report is the result of the optimal design, build and test of Voltage-Fed, Push-Pull Autotransformer battery discharger topology. The main thrust of this document is to achieve an optimal efficiency. The list of available parts is restricted to only those that are approved. Derating guidelines restrict the choice of power stage semiconductors in a manner that degrades efficiency so efficiency gains are sought by optimization of the power stage magnetics. A second goal of the design is to achieve optimal small and large signal performance. / Master of Science