# US 9,040,204 B1 · Reconfigurable microbial fuel cell

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 9,040,204 B1
- Document ID: US9040204B1
- Status: Granted
- Kind: B1
- Application number: 13/773,342
- Filed: 2013-02-21
- Granted: 2015-05-26
- Earliest claimed: 2013-02-21
- Assignees: The United States of America as represented by the Secretary of the Navy
- Applicants: Wayne P. Liu; David Bartholomew Chadwick; Kenneth E. Richter; Adriane Q. Wotawa-Bergen; Jeffrey Asher Kagan
- Inventors: Wayne P. Liu; David Bartholomew Chadwick; Kenneth E. Richter; Adriane Q. Wotawa-Bergen; Jeffrey Asher Kagan
- Web page: https://patentgrep.com/patent/US9040204B1

## CPC

- H01M 8/16: Biochemical fuel cells, i.e. cells in which microorganisms function as catalysts
- H01M 8/04313: characterised by the detection or assessment of variables; characterised by the detection or assessment of failure or abnormal function
- H01M 8/04544: {Voltage}
- H01M 8/04671: {of the individual fuel cell}
- H01M 8/04858: Electric variables
- H01M 2250/20: Fuel cells in motive systems, e.g. vehicle, ship, plane
- H02J 1/00: Circuit arrangements for DC mains or DC distribution networks
- H02J 2101/30: Fuel cells
- Y02E 60/50: Fuel cells
- Y02T 90/40: Application of hydrogen technology to transportation, e.g. using fuel cells
- H01M: PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H02J: ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION

## Abstract

A microbial fuel cell comprising: a first cathode; at least two anodes electrically connected to each other and to the cathode in a reconfigurable manner; and a processor operatively coupled to the anodes and configured to monitor a parameter of each anode to determine if a given anode has been oxygen-contaminated, and further configured to convert an oxygen-contaminated anode into a second cathode by reconfiguring the electrical connections.

## Claims

### Claim 1

A microbial fuel cell comprising:
a first cathode;
a load electrically connected to the first cathode;
at least two anodes, wherein each anode is electrically connected, via processor-controlled switches, to the load and to the first cathode in a reconfigurable manner such that any of the anodes may be converted into cathodes;
at least two oxygen barriers, one for each anode, wherein each oxygen barrier is an open container containing a portion of the sediment and a respective anode, and wherein each container is buried in the sediment such that the open container's opening faces away from the sea water; and
a processor operatively coupled to the anodes and configured to monitor a voltage output by each anode as compared to a reference electrode to determine if any anode has been oxygen-contaminated, and further configured to open the processor-controlled switch that connects a given oxygen-contaminated anode to the load and to close the processor-controlled switch that connects the given oxygen-contaminated anode to the first cathode in order to convert the given oxygen-contaminated anode into a second cathode, wherein the fuel cell operates in an oceanic environment, and wherein the anodes are buried in sea-bed sediment, and the cathode is positioned in seawater.

### Claim 2 (depends on 1)

The fuel cell of claim 1, further comprising an array of discreet elements, each element comprising a cathode, an electrical load, and an anode, wherein the elements and the components within each element are electrically connected via, processor-controlled switches, wherein the processor is configured to convert any given oxygen-contaminated anode from any given element into an additional cathode.

### Claim 3 (depends on 2)

The fuel cell of claim 2, wherein the processor is configured to dynamically reconfigure the electrical connections to achieve a desired anode-operating size So such that the fuel cell yields a desired operating voltage Vo.

### Claim 4 (depends on 2)

The fuel cell of claim 2, wherein each element further comprises a Capacitor, wherein the processor is configured to reconfigure the electrical connections to allow the capacitors to be charged in parallel and subsequently discharged in series.

### Claim 5

A microbial fuel cell comprising:
an array of discreet elements, each element comprising a cathode, an electrical load, and an anode, wherein the cathodes are positioned in a first environment and wherein the elements and the components within each element are electrically connected via processor-controlled switches, wherein each anode is electrically connected, via processor-controlled switches, to the respective load and to the respective cathode in a reconfigurable manner such that any of the anodes may be converted into additional cathodes;
an array of oxygen barriers, one for each anode, wherein each oxygen barrier is a sealed container containing a portion of sediment and a respective anode, wherein the sediment has a lower concentration of oxygen than the first environment;
a processor operatively coupled to the anodes and configured to monitor a voltage output by each anode as compared to a reference electrode to determine if any anode from any given element has been oxygen-contaminated, and further configured to open the processor-controlled switch that connects a given oxygen-contaminated anode to the respective load and to close the processor-controlled switch that connects the given oxygen-contaminated anode to the respective cathode in order to convert the given oxygen-contaminated anode into an additional cathode, wherein the fuel cell operates in an oceanic environment, and wherein the first environment is seawater.

### Claim 6 (depends on 5)

The fuel cell of claim 5, wherein the fuel cell is mounted to a mobile vehicle, such that each cathode is positioned outside the sealed containers.

### Claim 7

A method for controlling power output from a microbial fuel cell comprising the following steps:
monitoring, with a processor that is operatively coupled to each anode of an array of anodes, a parameter of each anode as compared to a reference electrode;
determining, with the processor, if any given anode has been oxygen-contaminated; and
converting the oxygen-contaminated anode into an additional cathode by opening, with the processor, a processor-controlled switch that connects the given oxygen-contaminated anode to a respective load and closing, with the processor, a processor-controlled switch that connects the given oxygen-contaminated anode to a respective cathode, wherein the anodes are surrounded by sea-bed sediment and the cathode is surrounded by seawater.

### Claim 8 (depends on 7)

The method of claim 7, wherein the parameter monitored by the processor is a voltage output by each of the array of anodes.

### Claim 9 (depends on 7)

The method of claim 7, wherein the steps monitoring, determining, and converting are performed without any human involvement.

### Claim 10 (depends on 9)

The method of claim 9, further comprising the steps of positioning each anode in an oxygen-impermeable, open container that contains a portion of the sea-bed sediment, and burying each container in the sea-bed sediment such that the open container's opening faces away from the sea water.

### Claim 11 (depends on 10)

The method of claim 10, further comprising the step of dynamically reconfiguring the electrical connections in response to changing environmental conditions to maintain a desired anode-operating size So such that the fuel cell yields a desired operating voltage Vo.

### Claim 12 (depends on 7)

The method of claim 7, further comprising the step of reconfiguring the electrical connections to allow capacitors within the microbial fuel cell to be charged in parallel and subsequently discharged in series.

### Claim 13 (depends on 7)

The method of claim 7, further comprising the steps of reducing anode exposure to oxygen by shielding each anode within a corresponding oxygen barrier in the form of a sealed container that contains an anaerobic medium, and mounting the microbial fuel cell to a vehicle capable of moving through water such that the cathode is positioned outside the container.