DISH SHAPED AND PRESSURE EQUALIZING ELECTRODES FOR ELECTROCHEMICAL BATTERIES

• US 20090142655A1
• Filed: 10/27/2008
• Published: 06/04/2009
• Est. Priority Date: 10/26/2007
• Status: Active Grant

• Current Assignee: G4 Synergetics, Inc.
• Original Assignee: G4 Synergetics, Inc.
• Inventors: Regalado, Julius, George, Anthony, Higgins, Martin Patrick, West, Jon Kenneth
• Granted Patent: US 8,632,901 B2
• Time in Patent Office: Days
• US Class Current: 429/128
• CPC Class Codes: H01M 10/0413 Large-sized flat cells or batteries for motive or stationary systems with plate-like electrodes
• CPC Class Codes: H01M 10/0418 with bipolar electrodes
• CPC Class Codes: H01M 10/044 with bipolar electrodes
• CPC Class Codes: H01M 10/282 with bipolar electrodes
• CPC Class Codes: H01M 10/345 Gastight metal hydride accumulators
• CPC Class Codes: H01M 10/4235 Safety or regulating additives or arrangements in electrodes, separators or electrolyte H01M10/4242 takes precedence
• CPC Class Codes: H01M 50/317 Re-sealable arrangements
• CPC Class Codes: H01M 50/342 Non-re-sealable arrangements
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product
• CPC Class Codes: Y10T 29/49108 Electric battery cell making

Abstract

A stacked battery has at least two cell segments arranged in a stack. Each cell segment may have a first electrode unit having a first active material electrode, a second electrode unit having a second active material electrode, and an electrolyte layer between the active material electrodes. One or more gaskets may be included in each cell segment to seal the electrolyte within the cell segment. The electrode units may be “dish shaped” and may contain a pressure equalization valve to reduce electrode unit deflection and improve pressure equalization between cell segments. The pressure equalization valve may allow a gas to diffuse through adjacent cell segments and may substantially prevent electrolyte from diffusing through.

Claims

1. A bi-polar battery comprising:

a positive mono-polar electrode unit;

a negative mono-polar electrode unit;

at least one bi-polar electrode unit stacked between said positive electrode unit and said negative electrode unit, wherein each of said electrode units are dish shaped.

an electrolyte layer provided between each pair of adjacent electrode units; and

a gasket positioned about each of said electrolyte layers, wherein each of said electrolyte layers is sealed by its respective gasket and its respective pair of adjacent electrode units.

2. The battery of claim 1, wherein the radius of curvature of each electrode unit is less than infinity.

3. The battery of claim 1, wherein the deflection of each electrode unit is reduced by the dish shape.

4. The battery of claim 1, wherein the at least one bi-polar electrode unit comprises a first side having a positive active material electrode layer and a second side having a negative active material electrode layer.

5. The battery of claim 4, wherein the thickness of the positive active material electrode layer and the negative active material electrode layer is uniform.

6. The battery of claim 4, wherein the thickness of the positive active material electrode layer and the negative active material electrode layer varies along the radial length of the at least one bi-polar electrode unit.

7. A bi-polar battery comprising:

a positive mono-polar electrode unit;

a negative mono-polar electrode unit;

at least one bi-polar electrode unit stacked between said positive electrode unit and said negative electrode unit, wherein the at least one bi-polar electrode unit comprises a pressure equalization valve;

an electrolyte layer provided between each pair of adjacent electrode units; and

a gasket positioned about each of said electrolyte layers, wherein each of said electrolyte layers is sealed by its respective gasket and its respective pair of adjacent electrode units.

8. The battery of claim 7, wherein the pressure equalization valve is resistant to chemical corrosion.

9. The battery of claim 7, wherein the pressure equalization valve has at least one of nanometer sized perforations and micrometer sized perforations.

10. The battery of claim 9, wherein an electrolyte is prevented from passing between adjacent electrolyte layers by the pressure equalization valve.

11. The battery of claim 9, wherein a gas is permitted to pass between adjacent electrolyte layers by the perforations in the pressure equalization valve.

12. The battery of claim 7, wherein the pressure equalization valve comprises:

a sealant; and

a graphitic carbon fiber bundle.

13. The battery of claim 12, wherein gas molecules are chemically transferred between adjacent electrolyte layers along the graphitic fiber bundle.

14. The battery of claim 12, wherein diffusion forces allow hydrogen molecules from an over pressurized electrolyte layer to travel along the surface of the graphitic fiber bundle.

15. The battery of claim 12, wherein an electrolyte is prevented from passing between adjacent electrolyte layers by the pressure equalization valve.

16. A bi-polar battery comprising:

a positive mono-polar electrode unit;

a negative mono-polar electrode unit;

at least one bi-polar electrode unit stacked between said positive electrode unit and said negative electrode unit, wherein the at least one bi-polar electrode unit comprises a rupture disk valve;

an electrolyte layer provided between each pair of adjacent electrode units; and

a gasket positioned about each of said electrolyte layers, wherein each of said electrolyte layers is sealed by its respective gasket and its respective pair of adjacent electrode units.

17. The battery of claim 16, wherein the stacked bi-polar battery comprises a domed top.

18. The battery of claim 17, wherein an orientation of the battery is maintained by the domed top, thereby preventing electrolyte to pass between adjacent electrolyte layers upon the rupturing of the rupture disk valve.

19. The battery of claim 16, wherein the rupture disk valve is resistant to chemical corrosion.

20. The battery of claim 16, wherein the rupture disk valve is disk shaped.

21. The battery of claim 16, wherein the pressure between each pair of adjacent electrode units is equalized by the rupture disk valve opening.

22. A method for producing a stacked bi-polar battery, the method comprising:

providing a positive mono-polar electrode unit (MPU) that comprises a first impermeable conductive substrate and a first positive active material electrode layer coated thereon, wherein each of the MPU, the first substrate, and the first positive electrode layer are dish shaped;

providing a first gasket upon the first substrate, wherein the space between the inner side walls of the first gasket and the portions of the MPU therebetween comprise a first space;

providing a first separator and a first electrolyte within the first space, wherein the first separator and the first electrolyte comprise a first electrolyte layer;

providing a plurality of bi-polar electrode units (BPUs) stacked upon the first gasket, wherein each of the plurality of BPUs are dish shaped;

providing a terminal gasket upon the terminal BPU, wherein the space between the inner side walls of the terminal gasket and the portions of the terminal BPU therebetween comprise a terminal space;

providing a terminal separator and a terminal electrolyte within the terminal space, wherein the terminal separator and the terminal electrolyte comprise a terminal electrolyte layer;

providing a negative MPU stacked on top of the terminal BPU, comprising a terminal impermeable conductive substrate and a terminal negative active material electrode layer coated thereon, wherein each of the negative MPU, the terminal substrate, and the terminal negative electrode layer are dish shaped.

23. The method of claim 22, wherein each of the plurality of BPUs comprises an impermeable conductive substrate, a pressure equalization valve, a positive electrode layer, and a negative electrode layer coated on opposite sides thereof.