RETICULATED AND CONTROLLED POROSITY BATTERY STRUCTURES

• US 20110070489A1
• Filed: 11/30/2010
• Published: 03/24/2011
• Est. Priority Date: 10/20/2000
• Status: Active Grant

• Current Assignee: Massachusetts Institute of Technology
• Original Assignee: Massachusetts Institute of Technology
• Inventors: Hellweg, Benjamin, Chiang, Yet-Ming
• Granted Patent: US 8,148,009 B2
• Time in Patent Office: Days
• US Class Current: 429/209
• CPC Class Codes: H01M 10/0525 Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• CPC Class Codes: H01M 2004/025 with shapes other than plane or cylindrical
• CPC Class Codes: H01M 4/04 Processes of manufacture in general
• CPC Class Codes: H01M 4/0402 Methods of deposition of the material
• CPC Class Codes: H01M 4/0404 by coating on electrode collectors
• CPC Class Codes: H01M 4/0414 by screen printing
• CPC Class Codes: H01M 4/0416 involving impregnation with a solution, dispersion, paste or dry powder H01M4/0438 takes precedence
• CPC Class Codes: H01M 4/0421 involving vapour deposition
• CPC Class Codes: H01M 4/0423 Physical vapour deposition
• CPC Class Codes: H01M 4/0426 Sputtering
• CPC Class Codes: H01M 4/0428 Chemical vapour deposition
• CPC Class Codes: H01M 4/0471 involving thermal treatment, e.g. firing, sintering, backing particulate active material, thermal decomposition, pyrolysis
• CPC Class Codes: H01M 4/0492 Chemical attack of the support material
• CPC Class Codes: H01M 4/13 Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
• CPC Class Codes: H01M 4/139 Processes of manufacture
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

The effective ionic conductivity in a composite structure is believed to decrease rapidly with volume fraction. A system, such as a bipolar device or energy storage device, has structures or components in which the diffusion length or path that electrodes or ions must traverse is minimized and the interfacial area exposed to the ions or electrons is maximized. The device includes components that can be reticulated or has a reticulated interface so that an interface area can be increased. The increased interfacial perimeter increases the available sites for reaction of ionic species. Many different reticulation patterns can be used. The aspect ratio of the reticulated features can be varied. Such bipolar devices can be fabricated by a variety of methods or procedures. A bipolar device having structures of reticulated interface can be tailored for the purposes of controlling and optimizing charge and discharge kinetics. A bipolar device having graded porosity structures can have improved transport properties because the diffusion controlling reaction kinetics can be modified. Graded porosity electrodes can be linearly or nonlinearly graded. A bipolar device having perforated structures also provides improved transport properties by removing tortuosity and reducing diffusion distance.

Claims

1. An electrode comprising a plurality of channels defined therein, wherein the electrode is constructed and arranged to allow diffusion of an ionic species from an electrolyte to a surface thereof.

2. The electrode of claim 1, wherein at least some of the channels extend substantially across the electrode.

3. The electrode of claim 1, wherein an end of at least some of the channels is in ionic communication with the electrolyte.

4. The electrode of claim 1, wherein at least some of the channels are substantially parallel.

5. The electrode of claim 1, wherein at least some of the channels are disposed from each other at a distance that is less than a smallest dimension of the electrode.

6. A battery comprising an electrode in contact with an electrolyte, the electrode having a plurality of channels defined therein, wherein the electrode is constructed and arranged to allow diffusion of an ionic species from the electrolyte to a surface thereof.

7. The battery of claim 6, wherein at least some of the channels extend substantially across the electrode.

8. The battery of claim 6, wherein an end of at least some of the channels is in ionic communication with the electrolyte.

9. The battery of claim 6, wherein at least some of the channels are substantially parallel.

10. The battery of claim 6, wherein at least some of the channels are disposed from each other at a distance that is less than a smallest dimension of the electrode.

11. The battery of claim 6, wherein the electrolyte is solid.

12. The battery of claim 6, wherein the ionic species is Li⁺.

13. A battery comprising at least one perforated electrode in ionic communication with an electrolyte.

14. The battery of claim 13, wherein the perforated electrode comprises a plurality of channels defined therein, and wherein the electrode is constructed and arranged to allow diffusion of an ionic species from an electrolyte to a surface thereof

15. The battery of claim 14, wherein at least some of the channels extend substantially across the electrode.

16. The battery of claim 14, wherein an end of at least some of the channels is in ionic communication with the electrolyte.

17. The battery of claim 14, wherein at least some of the channels are substantially parallel.

18. The battery of claim 14, wherein at least some of the channels are disposed from each other at a distance that is less than a smallest dimension of the electrode.

19. The battery of claim 14, wherein the electrolyte is solid.

20. The battery of claim 14, wherein the ionic species is Li⁺.