Auxiliary electrode for lithium-ion battery

• US 9,587,321 B2
• Filed: 03/31/2015
• Issued: 03/07/2017
• Est. Priority Date: 12/09/2011
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Viavattine, Joseph J., Jain, Gaurav, Tamirisa, Prabhakar A.
• Primary Examiner(s): Stagg, Miriam
• Assistant Examiner(s): LYLES-IRVING, CARMEN V
• Application Number:
  US14/675,106
• Publication Number:
  US 20150275384A1
• Time in Patent Office: 707 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: C25D 7/0642 Anodes
• CPC Class Codes: H01M 10/044 with bipolar electrodes
• CPC Class Codes: H01M 10/0445 Multimode batteries, e.g. containing auxiliary cells or electrodes switchable in parallel or series connections
• 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 10/058 Construction or manufacture
• CPC Class Codes: H01M 10/425 Structural combination with electronic components, e.g. electronic circuits integrated to the outside of the casing printed circuits H05K1/00
• CPC Class Codes: H01M 2004/027 Negative electrodes
• CPC Class Codes: H01M 4/0407 by coating on an electrolyte layer
• 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

An auxiliary electrode for a lithium-ion battery includes a lithium source material. The auxiliary electrode is configured to selectively couple to a negative electrode of a lithium-ion battery to provide lithium for formation of a solid-electrolyte-inter-phase layer on a negative electrode.

Claims

1. A method for forming a solid electrolyte interface in a lithium-ion battery comprising:

providing a lithium-ion battery having a positive electrode, a negative electrode, and an auxiliary electrode having a lithium source material, the electrodes being in contact with a common electrolyte;

charging the battery by coupling the positive electrode to the negative electrode with a voltage source, such that lithium from the positive electrode forms at least a portion of a solid electrolyte interface on the negative electrode;

after charging the battery, selectively coupling the auxiliary electrode to the negative electrode for a first predetermined time, such that lithium from the auxiliary electrode forms another portion of the solid electrolyte interface on the negative electrode; and

uncoupling the auxiliary electrode from the negative electrode.

2. The method of claim 1, wherein coupling of the auxiliary electrode to the negative electrode occurs during a formation process of the battery prior to an initial discharge of the battery.

3. The method of claim 1, wherein coupling of the auxiliary electrode to the negative electrode occurs after an initial discharge of the battery.

4. The method of claim 3, wherein coupling of the auxiliary electrode to the negative electrode is configured to occur at regular intervals.

5. The method of claim 1, wherein coupling of the auxiliary electrode to the negative electrode occurs prior to charging the battery.

6. The method of claim 1, wherein coupling of the auxiliary electrode to the negative electrode includes coupling a voltage source to the negative electrode and the auxiliary electrode.

7. The method of claim 1, wherein coupling of the auxiliary electrode to the negative electrode includes coupling a resistance to the negative electrode and the auxiliary electrode.

8. The method of claim 1, further comprising:

recoupling the auxiliary electrode to the negative electrode after an initial discharge of the battery for a second predetermined time, such that while the auxiliary electrode is coupled to the negative electrode, additional lithium from the auxiliary electrode forms another portion of the solid electrolyte interface on the negative electrode; and

uncoupling the auxiliary electrode from the negative electrode.

9. The method of claim 1, wherein the auxiliary electrode comprises a lithium source material.

10. The method of claim 7, wherein a cycling potential of the auxiliary electrode is less than that of the negative electrode.

11. The method of claim 1, wherein the negative electrode comprises an active material negative active material selected from the group consisting of a tin alloy and a silicon alloy.

12. The method of claim 1, wherein the auxiliary electrode includes a lithium source of material that is a denser source of lithium than a positive active material of the positive electrode.

13. The method of claim 1, wherein the first predetermined time is configured to allow an amount of lithium approximately equivalent to 15% of a negative capacity of the negative electrode to be delivered from the auxiliary electrode to the negative electrode.

14. The method of claim 8, wherein the recoupling is initiated in response to occurrence of a predetermined condition of the lithium-ion battery.

15. The method of claim 14, wherein the predetermined condition comprises at least one of passage of a predetermined time period, a predetermined number of charge cycles, a predetermined number of discharge cycles, and a predetermined loss of capacity.

16. The method of claim 8, wherein the second predetermined time is configured to allow an amount of lithium approximately equivalent to 1% of a negative capacity of the negative electrode to be delivered from the auxiliary electrode to the negative electrode.