Microbial fuel cells use bacteria as the catalysts to oxidize organic and inorganic matter to generate current that supplies implantable medical devices (Logan, 2006). A critical review from Microbial Fuel Cells Focus Group at Penn State University reports that a widely used and inexpensive type of microbial fuel cell is designed with two chambers connected by a tube containing a carton exchange membrane. The choice of membrane in this design is crucial: the membrane has to allow protons to pass between the chambers, but not the substrate or election acceptor in the cathode chamber (Logan, 2006). The design of microbial fuel cells hence involves knowledge in microbiology, electrochemistry, materials, and environmental engineering. Development in microbial fuel cells has great potential to be used as a renewable and bio-compatible energy source for commercial as well as medical applications. However, it is a field of research that currently lacks established terminology and systematic method of analysis.