Fuel cell with recovering unit and method for driving the same

• US 20070207352A1
• Filed: 02/28/2007
• Published: 09/06/2007
• Est. Priority Date: 03/03/2006
• Status: Active Grant

• Current Assignee: Samsung SDI Company Limited
• Original Assignee: Samsung SDI Company Limited
• Inventors: Kim, Dong Hyun, Park, Jung Kurn
• Granted Patent: US 8,900,762 B2
• Time in Patent Office: Days
• US Class Current: 429/414
• CPC Class Codes: H01M 8/04097 with recycling of the reactants H01M8/04119, H01M8/04104 take precedence
• CPC Class Codes: H01M 8/04141 by water containing exhaust gases
• CPC Class Codes: H01M 8/04164 by condensers, gas-liquid separators or filters
• CPC Class Codes: H01M 8/04201 Reactant storage and supply, e.g. means for feeding, pipes
• CPC Class Codes: H01M 8/04291 Arrangements for managing water in solid electrolyte fuel cell systems H01M8/04119 takes precedence
• CPC Class Codes: H01M 8/1011 Direct alcohol fuel cells [DAFC], e.g. direct methanol fuel cells [DMFC]
• CPC Class Codes: Y02E 60/50 Fuel cells

Abstract

A fuel cell with a recovering unit and a method of driving the same are disclosed. In one embodiment, the fuel cell includes i) an electric generator to generate electricity based on electrochemical reaction, ii) a recovering unit to recover and mix the fuel, unreacted fuel, and gas and water produced by the electrochemical reaction, and supply the mixed fuel to the electric generator, wherein the recovering unit comprises a valve, configured to discharge gas, which is selectively opened and closed depending on the operation of the fuel cell. With this configuration, the gas or the fuel is not introduced into the electric generator, even though the recovering unit is inclined or turned over. Further, even though the fuel cell is not in use for a long time, the mixed fuel is prevented from evaporating through the discharging pipe.

Claims

1. A fuel cell, comprising:

an electricity generator configured to generate electricity based on an electrochemical reaction;

a fuel container configured to store a raw fuel;

a recovering unit configured to mix i) the raw fuel, ii) an unreacted fuel which has not participated in the electrochemical reaction, and iii) water produced from the electrochemical reaction so as to produce mixed fuel, and supply the mixed fuel to the electricity generator; and

an oxygen provider configured to supply oxygen to the electricity generator,

wherein the recovering unit comprises;

a housing connected to and communicating fluid with the electricity generator and the fuel container;

a discharging pipe located inside the housing configured to discharge gas recovered from the electricity generator, and having a first end extending to the outside of the housing and a second end extending to the inside of the housing; and

a first valve located in the discharging pipe.

2. The fuel cell according to claim 1, wherein the recovering unit further comprises a second valve located in an anode recovering pipe which connects the housing with an outlet of an anode electrode of the electricity generator so as to communicate fluid with each other.

3. The fuel cell according to claim 2, wherein the recovering unit further comprises a third valve located in a cathode recovering pipe which connects the housing with an outlet of a cathode electrode of the electricity generator so as to communicate fluid with each other.

4. The fuel cell according to claim 3, wherein each of the second valve and the third valve comprises an on/off valve or a check valve.

5. The fuel cell according to claim 4, wherein the first valve comprises an on/off valve.

6. The fuel cell according to claim 1, wherein the second end of the discharging pipe is connected to a float.

7. The fuel cell according to claim 2, wherein the housing comprises a porous material placed on an inner surface thereof and adjacent to the anode recovering pipe.

8. The fuel cell according to claim 3, wherein the recovering unit further comprises a fourth valve placed in a mixed fuel supplying pipe which connects the housing with an inlet of the anode electrode of the electricity generator so as to communicate fluid with each other.

9. The fuel cell according to claim 8, wherein the mixed fuel supplying pipe is connected with a fuel pump, and the fourth valve is placed in the front of the fuel pump.

10. The fuel cell according to claim 8, wherein the mixed fuel supplying pipe is connected with a fuel pump, and the fourth valve is placed in the back of the fuel pump.

11. A method of driving a fuel cell, comprising:

supplying hydrogen containing mixed fuel and oxygen to an electricity generator via a first supplying line and a second supplying line;

generating electricity by way of an electrochemical reaction between hydrogen and oxygen in the electricity generator;

recovering, at a recovering unit, byproducts produced from the electrochemical reaction via a recovering path;

discharging gas contained in the byproducts from the recovering unit to the environment; and

mixing i) unreacted fuel contained in the byproducts, ii) water and iii) raw fuel so as to generate the hydrogen containing mixed fuel while discharging the gas to the environment.

12. The method according to claim 11, wherein the discharging is stopped when the hydrogen containing mixed fuel and oxygen are not supplied to the electricity generator.

13. The method according to claim 11, wherein the recovering path is shut down when the hydrogen containing mixed fuel and oxygen are not supplied to the electricity generator.

14. A fuel provider for use with a fuel cell, comprising:

a first inlet configured to receive a first fuel;

a second inlet configured to receive a second fuel, wherein the first and the second fuels have different concentrations from each other and wherein one of the first and second fuels includes gas;

a third inlet configured to receive water;

a first outlet configured to provide a mixed fuel based on the first and second fuels; and

a second outlet configured to discharge the gas,

wherein the fuel provider is configured to selectively close at least one of the second outlet and third inlet.

15. The fuel provider of claim 14, wherein the second outlet is configured to be closed when the fuel cell does not operate.

16. The fuel provider of claim 14, wherein the third inlet is configured to be closed when the fuel cell is inclined.

17. The fuel provider of claim 16, further comprising an inclination detection sensor configured to detect the inclination of the fuel cell.

18. The fuel provider of claim 14, wherein the fuel provider includes a float which is configured to discharge only the gas.

19. A method of driving a fuel cell having an anode side and a cathode side, the method comprising:

receiving a first fuel;

receiving a second fuel, wherein the first and the second fuels have different concentrations from each other and wherein one of the first and second fuels includes gas;

generating a mixed fuel based on the first and second fuels;

discharging the gas; and

receiving water from the cathode side, wherein the mixed fuel is not permitted to enter the cathode side when the fuel cell is inclined.

20. The method of claim 19, wherein the gas is not discharged when the fuel cell does not operate.