MICROBIAL FUEL CELLS

• US 20080286624A1
• Filed: 05/18/2007
• Published: 11/20/2008
• Est. Priority Date: 05/18/2007
• Status: Active Grant

• Current Assignee: Toyota Motor Corporation, University Of Massachusetts
• Original Assignee: Toyota Engineering and Manufacturing North America Inc (Toyota Motor Corporation), University Of Massachusetts
• Inventors: Zhang, Minjuan, Jia, Hongfei, Lovley, Derek R., Nevin, Kelly P.
• Granted Patent: US 8,283,076 B2
• Time in Patent Office: Days
• US Class Current: 429/27
• CPC Class Codes: H01M 4/9008 Organic or organo-metallic compounds
• CPC Class Codes: H01M 4/96 Carbon-based electrodes
• CPC Class Codes: H01M 8/16 Biochemical fuel cells, i.e. cells in which microorganisms function as catalysts
• CPC Class Codes: Y02E 60/50 Fuel cells

Abstract

A microbial fuel cell is provided according to embodiments of the present invention including electricigenic microbes containing at least about 0.075 milligrams of protein per square centimeter of the anode surface area. In particular embodiments, the electricigenic microbes are disposed on the anode such that at least about 90% of the portion of the anode surface area has a layer of electricigenic microbes, the layer greater than about 1 micron in thickness. This thickness is indicative of the layer including at least a first stratum of electricigenic microbes in direct contact with the anode and a second stratum of electricigenic microbes in direct contact with the first stratum such that the second stratum is in indirect contact with the anode.

Claims

1. A microbial fuel cell, comprising:

an anode having an anode surface area, a cathode having a cathode surface area, a cation exchange membrane disposed between the anode and the cathode, and a plurality of electricigenic microbes disposed on the anode and forming a plurality of colonies spaced from each other improving a mass transfer of the plurality of electricigenic microbes increasing a power density of the microbial fuel cell.

2. The microbial fuel cell of claim 1 wherein the colonies form pillar structures having a height of from 20 to 50 microns.

3. The microbial fuel cell of claim 1 wherein the colonies have a spacing up to 40 microns.

4. The microbial fuel cell of claim 1 wherein the plurality of electricigenic microbes comprise at least about 0.075 milligrams of protein per square centimeter of the anode surface area.

5. The microbial fuel cell of claim 1 wherein the plurality of electricigenic microbes form a biofilm having a thickness greater than 1 micron.

6. The microbial fuel cell of claim 1 wherein the plurality of electricigenic microbes form pili allowing electron transport between the plurality of electricigenic microbes.

7. The microbial fuel cell of claim 1 wherein the plurality of electricigenic microbes is Geobacteraceae.

8. The microbial fuel cell of claim 1 wherein the plurality of electricigenic microbes is a substantially pure population of electricigenic microbes.

9. The microbial fuel cell of claim 8 wherein the plurality of electricigenic microbes is a substantially pure population of Geobacter sulfurreducens.

10. The microbial fuel cell of claim 1 wherein the cathode is an air cathode.

11. The microbial fuel cell of claim 1 wherein the fuel cell has a power density of from 100 mA/m² to 4.56 A/m².

12. The microbial fuel cell of claim 1 wherein the anode is substantially non-toxic to the plurality of microbes.

14. A microbial fuel cell, comprising:

an anode having an anode surface area, a cathode having a cathode surface area, a cation exchange membrane disposed between the anode and the cathode, and a plurality of electricigenic microbes disposed on the anode and forming a plurality of colonies having pillars spaced from each other improving a mass transfer of the plurality of electricigenic microbes increasing a power density of the microbial fuel cell.

15. A microbial fuel cell, comprising:

an anode having an anode surface area, a cathode having a cathode surface area, a cation exchange membrane disposed between the anode and the cathode, and a plurality of electricigenic microbes disposed on the anode and forming a plurality of colonies spaced from each other improving a mass transfer of the plurality of electricigenic microbes increasing a power density of the microbial fuel cell and wherein the plurality of electricigenic microbes form a bio film having a thickness greater than one micron.

13. The microbial fuel cell of claim 15 wherein the anode is selected from:

graphite, porous graphite, packed graphite powder, carbon cloth carbon felt, carbon paper, carbon wool, a conductive metal, a conductive polymer and combinations of any of these.