ELECTROCHEMICAL CELL

• US 20110050235A1
• Filed: 08/28/2009
• Published: 03/03/2011
• Est. Priority Date: 08/28/2009
• Status: Active Grant

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Bogdan, David Charles JR., Vallance, Michael Alan, Iacovangelo, Charles Dominic
• Granted Patent: US 8,766,642 B2
• Time in Patent Office: Days
• US Class Current: 324/426
• CPC Class Codes: H01M 10/399 Cells with molten salts
• CPC Class Codes: H01M 10/4207 for several batteries or cells simultaneously or sequentially
• CPC Class Codes: H01M 10/4285 Testing apparatus
• CPC Class Codes: H01M 10/482 for several batteries or cells simultaneously or sequentially
• CPC Class Codes: H01M 4/40 Alloys based on alkali metals
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y10T 29/49108 Electric battery cell making

Abstract

An electrochemical cell is provided. The electrochemical cell comprises a cathode compartment, wherein a metal in a solid form is disposed in the cathode compartment. The electrochemical cell further comprises a separator, an anode compartment, and at least one contact device disposed in the cathode compartment or in the anode compartment. The contact device is suspended from the top of the electrochemical cell in the cathode compartment or in the anode compartment. The electrochemical cell is in a ground state. An electrochemical cell during its working is also provided. Methods for using and manufacturing the electrochemical cell are also provided. The electrochemical cell is used to determine a state-of-charge of a source.

Claims

1. An electrochemical cell, comprising:

a cathode compartment, wherein a metal in a solid form is disposed in the cathode compartment;

a separator;

an anode compartment;

at least one contact device disposed in the cathode compartment or in the anode compartment; and

wherein the contact device is suspended from the top of the electrochemical cell in the cathode compartment or in the anode compartment;

wherein the electrochemical cell is in a ground state.

2. The electrochemical cell as defined in claim 1, wherein the cell is used to determine a state-of-charge of a source.

3. The electrochemical cell as defined in claim 2, wherein the source comprises a high-temperature rechargeable electrochemical cell, a potentiostat where the electrochemical cell is used for calibration, or a battery management interface where the electrochemical cell is used for calibration.

4. The electrochemical cell as defined in claim 1, wherein the electrochemical cell has a reversible potential of 0 volts.

5. The electrochemical cell as defined in claim 1, wherein the electrochemical cell has a resistance of less than 0.01 Ohms.

6. The electrochemical cell as defined in claim 1, wherein the electrochemical cell has a voltage drop of about 0 Volts under a load.

7. The electrochemical cell as defined in claim 1, wherein the metal comprises sodium or potassium.

8. The electrochemical cell as defined in claim 1, wherein the metal comprises sodium.

9. The electrochemical cell as defined in claim 1, wherein the electrochemical cell functions at a temperature greater than the melting point of the metal.

10. The electrochemical cell as defined in claim 1, wherein the contact device comprises:

an insulated metal wire having one end of the wire which is disposed inside the cathode compartment or in the anode compartment, exposed.

11. The electrochemical cell as defined in claim 1, wherein the contact device comprises a non-insulated metal wire.

12. An electrochemical cell, comprising:

a cathode compartment, wherein a metal is disposed in the cathode compartment in a solid form in a ground state of the electrochemical cell, and wherein the metal is in a molten state during working of the cell;

a separator;

an anode compartment, wherein the anode compartment is empty in the ground state of the electrochemical cell and is filled with the metal reduced from metal ions that move from the cathode compartment to the anode compartment through the separator during the working of the cell; and

at least one contact device disposed in the cathode compartment or in the anode compartment, wherein the contact device is suspended from the top of the electrochemical cell in the cathode compartment or in the anode compartment, and wherein the contact device detects the level of the metal in its molten state in the cathode compartment or in the anode compartment during the working of the cell.

13. The electrochemical cell as defined in claim 12, wherein a chemical reaction M→

M⁺+e⁻

occurs in both the cathode compartment and the anode compartment during the working of the cell.

14. The electrochemical cell as defined in claim 13, wherein the separator allows only movement of the M⁺ions between the cathode compartment and the anode compartment.

15. The electrochemcial cell as defined in claim 12, wherein the electrochemical cell is used to determine a state-of-charge of a source.

16. The electrochemical cell as defined in claim 12, wherein the contact device comprises:

an insulated metal wire having one end of the wire which is disposed inside the cathode component or in the anode compartment, exposed.

17. The electrochemical cell as defined in claim 16, wherein the exposed end of the metal wire comes in contact with the liquid metal in the cathode compartment when the level of liquid sodium in the cathode compartment or in the anode compartment increases during the working of the cell.

18. The electrochemical cell as defined in claim 12, wherein a state-of-charge is determined based on when the liquid metal is in contact with the exposed end of the insulated metal wire and when the liquid metal is not in contact with the exposed end of the insulated metal wire.

19. The electrochemical cell as defined in claim 12, wherein the contact device comprises a non-insulated metal wire.

20. The electrochemical cell as defined in claim 18, wherein the non-insulated metal wire is always in contact with the liquid metal in the cathode compartment or in the anode compartment and a state-of-charge is calculated based on a change in resistance when the level of liquid sodium in the cathode compartment or in the anode compartment increases or decreases.

21. The electrochemical cell as defined in claim 12, wherein the electrochemical cell has a reversible potential of 0 volts.

22. The electrochemical cll as defined in claim 12, wherein the electrochemical cell has a resistance of less than 0.01 Ohms.

23. The electrochemical cell as defined in claim 12, wherein the electrochemical cell has a voltage drop of about 0 Volts under a load.

24. The electrochemical cell as defined in claim 12, wherein the metal comprises sodium or potassium.

25. The electrochemical cell as defined in claim 12, wherein the metal comprises sodium.

26. The electrochemical cell as defined in claim 12, wherein the electrochemical cell functions at a temperature greater than the melting point of the metal.

27. An electrochemical device, comprising:

an electrochemical cell comprising, a cathode compartment, wherein a metal is disposed in the cathode compartment in a solid form in a ground state of the electrochemical cell, and wherein the metal is in a molten state during working of the cell;

a separator;

an anode compartment, wherein the anode compartment is empty in the ground state of the electrochemical cell and is filled with the metal from reduced metal ions that move from the cathode compartment to the anode compartment through the separator during the working of the cell; and

at least one contact device disposed in the cathode compartment or in the anode compartment, wherein the contact device is suspended from the top of the electrochemical cell in the cathode compartment or in the anode compartment, wherein the contact device detects the level of the metal in its molten state in the cathode compartment or in the anode compartment during the working of the cell;

a cathode current collector in contact with the cathode compartment;

an anode current collector in contact with the anode compartment; and

a source connected in series with the electrochemical cell.

28. The electrochemical device as defined in claim 27, wherein the source comprises a high-temperature rechargeable electrochemical cell, a potentiostat where the electrochemical cell is used for calibration, or a battery management interface where the electrochemical cell is used for calibration.

29. A method of determining the state-of-charge of a source comprising:

connecting the source in series with a cathode current collector and an anode current collector of an electrochemical cell, wherein the electrochemical cell comprises,

a cathode compartment, wherein a metal is disposed in the cathode compartment in a solid form in a ground state of the electrochemical cell, and wherein the metal is in a molten state during working of the cell;

a separator;

an anode compartment;

wherein the anode compartment is empty in the ground state of the electrochemical cell and is filled with the metal from reduced metal ions that move from the cathode compartment to the anode compartment through the separator during the working of the cell; and

at least one contact device disposed in the cathode compartment or in the anode compartment;

wherein the contact device is suspended from the top of the electrochemical cell in the cathode compartment or in the anode compartment, wherein the contact device detects the level of the metal in its molten state in the cathode compartment or in the anode compartment during the working of the cell.

30. A method for forming an electrochemical cell comprising:

providing a cathode compartment, wherein a metal is disposed in the cathode compartment in a solid form in a ground state of the electrochemical cell, and wherein the metal is in a molten state during working of the cell;

a separator;

an anode compartment;

wherein the anode compartment is empty in the ground state of the electrochemical cell and is filled with the metal from reduced metal ions that move from the cathode compartment to the anode compartment through the separator during the working of the cell; and

at least one contact device disposed in the cathode compartment or in the anode compartment;

wherein the contact device is suspended from the top of the electrochemical cell in the cathode compartment or in the anode compartment, wherein the contact device detects the level of the metal in its molten state in the cathode compartment or in the anode compartment during the working of the cell.

31. An electrochemical reference cell that is operable in a ground state to indicate a state-of-charge of an electrochemical duty cell, comprising:

a separator that defines an interior volume of the electrochemical cell into a cathode compartment having a cathodic material disposed therein; and

an anode compartment;

a contact device disposed in the cathode compartment or in the anode compartment, and that is capable of communicating a change in its electrical resistance to a controller.

32. A system comprising the electrochemical reference cell as defined in claim 31, wherein the contact device is responsive to a change in contact surface area of an electrolyte by changing its electrical resistance.