Patent ID: 8734968

Claim:
A microbial fuel cell comprising: an anode portion comprising an anode, wherein a specific surface area of the anode is about 500 cm −1 or greater; a cathode portion comprising a cathode, wherein the ratio of the distance between the anode and the cathode to the cross-sectional area (cm 2 ) through which ionic conduction occurs is 0.0009 cm −1 or lower; a cation exchange membrane positioned between the anode and the cathode, wherein the anode portion and the cation exchange membrane define an anode chamber having a volume of between about 1 μL and about 100 μL, and the cathode portion and the cation exchange membrane define a cathode chamber having a volume of between about 1 μL and about 100 μL; an anolyte in the anode chamber, the anolyte comprising L-cysteine as an oxygen scavenger; a catholyte in the cathode chamber; and an electrically conductive biofilm formed on the anode and comprising anode-respiring bacteria comprising Geobacter sp., wherein the Coulombic efficiency of the microbial fuel cell is at least 30%.