Near zero volt storage tolerant electrochemical cells through reversible ion management

• US 10,193,354 B2
• Filed: 04/06/2017
• Issued: 01/29/2019
• Est. Priority Date: 04/06/2016
• Status: Active Grant

• Current Assignee: Rochester Institute of Technology
• Original Assignee: Rochester Institute of Technology
• Inventors: Crompton, Kyle, Landi, Brian
• Primary Examiner(s): Diao, M Baye
• Application Number:
  US15/481,115
• Publication Number:
  US 20170324255A1
• Time in Patent Office: 663 Days
• Field of Search: 320149
• 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 10/054 Accumulators with insertion or intercalation of metals other than lithium, e.g. with magnesium or aluminium
• CPC Class Codes: H01M 10/0568 characterised by the solutes
• CPC Class Codes: H01M 10/058 Construction or manufacture
• CPC Class Codes: H01M 10/42 Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells H01M10/60 takes precedence
• CPC Class Codes: H01M 10/48 Accumulators combined with arrangements for measuring, testing or indicating the condition of cells, e.g. the level or density of the electrolyte constructional details of current conducting connections for detecting conditions inside cells or batteries, e.g. details of voltage sensing terminals, H01M50/569
• CPC Class Codes: H01M 10/63 Control systems charging or discharging in response to temperature H01M10/44 , H01M10/443; measurement of temperature H01M10/48 , H01M10/486
• CPC Class Codes: H01M 14/00 Electrochemical current or voltage generators not provided for in groups H01M6/00 - H01M12/00; Manufacture thereof
• CPC Class Codes: H01M 2010/4271 Battery management systems including electronic circuits, e.g. control of current or voltage to keep battery in healthy state, cell balancing
• CPC Class Codes: H01M 2010/4292 Aspects relating to capacity ratio of electrodes/electrolyte or anode/cathode
• CPC Class Codes: H01M 2300/002 Inorganic electrolyte
• CPC Class Codes: H01M 4/525 of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy
• CPC Class Codes: H01M 4/587 for inserting or intercalating light metals
• CPC Class Codes: H01M 4/94 Non-porous diffusion electrodes, e.g. palladium membranes, ion exchange membranes
• CPC Class Codes: H02J 7/00041 in response to measured battery parameters, e.g. voltage, current or temperature profile
• CPC Class Codes: H02J 7/007184 in response to battery voltage gradient
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02E 60/50 Fuel cells
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries

Abstract

An electrochemical cell having a positive electrode; a negative electrode and an electrolyte, wherein the electrochemical cell contains reversible ions in an amount sufficient to maintain a negative electrode potential verses reference level below a negative electrode damage threshold potential of the cell and a positive electrode potential verses reference level above a positive electrode damage threshold potential of the cell under an applied load at a near zero cell voltage state, such that the cell is capable of recharge from the near zero cell voltage state, and method for its production is disclosed.

Claims

1. An electrochemical cell, comprising:

a positive electrode;

a negative electrode; and

an electrolyte, wherein the electrochemical cell contains reversible ions in an amount sufficient to maintain a negative electrode potential verses reference level that is less than a damage potential of the negative electrode and a positive electrode potential verses reference level that is greater than a damage potential of the positive electrode of the cell under an applied load at a near zero cell voltage state, such that the cell is capable of recharge from the near zero cell voltage state.

2. The cell of claim 1, wherein the applied load is fixed or variable or a combination thereof.

3. The cell of claim 1, wherein the reversible ions comprise lithium, sodium, magnesium, aluminum, hydrogen, or a combination thereof.

4. The cell of claim 1, wherein the positive electrode comprises an active material and the negative electrode comprises an active material each electrode configured to allow intercalation/alloying/deposition and de-intercalation/de-alloying/stripping of the reversible ions.

5. The cell of claim 1, wherein the negative electrode comprises a carbon allotrope, Ge, Si, Al, metal oxide, titanate material or Sn as a secondary active material that has an intercalation/alloying and de-intercalation/de-alloying potential that is less than the damage potential of a positive electrode comprising active materials;

and optionally ionated.

6. The cell of claim 1, wherein the cell is tolerant to near zero volt storage under an applied load over a range of temperatures from −

100°

C. to 200°

C.

7. The cell of claim 1, further comprising a resistor comprising a suitable fixed or variable load applied to the electrodes based on the capacity of the cell to realize a near zero volt condition during storage.

8. The cell of claim 7, wherein the resistor comprises a safety clip structure that minimizes user risk during storage and handling, wherein the safety clip structure can be fabricated with user controls and readout device, display or transmitted signal which monitors cell voltage for protection and disassembly.

9. A battery comprising multiple electrochemical cells according to claim 1, which battery is capable of a near zero cell voltage state when the multiple electrochemical cells are under an applied load without significant performance degradation upon recharge.

10. A method for providing an electrochemical cell which manages an amount of reversible ions that enables a near zero voltage storage for prolonged periods of time under an applied load capable of recharge without significant degradation of discharge performance, comprising:

a) fabricating a first electrochemical cell having a negative electrode, a positive electrode, a third electrode, and an electrolyte;

b) measuring the voltage difference between the negative electrode and the third electrode to determine the electrochemical potential of the negative electrode verses reference level and measuring the voltage difference between the positive electrode and the third electrode to determine the electrochemical potential of the positive electrode verses reference level upon application of an applied load that electrically connects the positive electrode and negative electrode to the first electrochemical cell as the voltage difference between the positive electrode and the negative electrode of the first electrochemical cell voltage, reaches a near zero volts;

c) determining the electrode asymptotic potential from the measured electrochemical potential of the negative electrode verses reference level and the positive electrode verses reference level in the first electrochemical cell;

d) adjusting the amount of reversible ions in the first electrochemical cell based upon the determined electrode asymptotic potential from the first electrochemical cell, or fabricating a second electrochemical cell having a negative electrode, a positive electrode, a third electrode, and an electrolyte and adjusting the amount of reversible ions in the second electrochemical cell, based upon the determined electrode asymptotic potential from the first electrochemical cell; and

e) repeating steps a), b), c) and d) until an amount of the reversible ions in the cell is identified that achieves the negative electrode potential verses reference level below a negative electrode damage threshold potential of the cell and the positive electrode potential verses reference level above a positive electrode damage threshold potential of the cell under the applied load at a near zero cell voltage state, and optionally removing the third electrode.

11. The method of claim 10, wherein step a) is determined by measuring with a reference electrode the electrochemical potentials of the negative electrode and positive electrode as the electrochemical potentials asymptote towards each other during an applied load condition and asymptote towards an intermediate potential.

12. The method of claim 10, wherein determining the electrode asymptotic potential comprises constructing multiple cells with different amounts of reversible ions added or subtracted, or constructing a single cell wherein reversible ions can be added or subtracted in situ by electrochemical, physical or chemical means after measurement of the electrode potentials during the application of the applied load, the amount of reversible ions in the cell design is added or subtracted to change the electrode potentials during the applied load via feedback from measurements over a range of temperatures that can range from −

100°

C. to 200°

C.

13. The method of claim 12, wherein the amount of reversible ions is adjusted in the cell via electrochemical, chemical or physical addition/subtraction of ions to the negative electrode, positive electrode or both.

14. The method of claim 10, wherein the reversible ion is lithium.

15. The method of claim 14, wherein reversible lithium ions are added by electrochemically inserting lithium ions into the negative electrode prior to cell assembly.

16. The method of claim 14, wherein reversible lithium ions are added or subtracted by immersing the electrodes in a bath of electrolyte and the reversible lithium is added or subtracted electrochemically to or from either the positive or negative electrode from the third electrode or a fourth electrode prior to final assembly of the cell.

17. The method of claim 14, wherein the reversible lithium ions are electrochemically added to or subtracted from the cell to either the positive or negative electrode from the third electrode or a fourth electrode that is removed from the cell after addition of the reversible lithium ions.

18. The method of claim 14, wherein the amount of reversible lithium ions is managed by the stoichiometry and charge/discharge performance of the active materials in the cell such that negative electrode potential verses reference level below a negative electrode damage threshold potential of the cell and the positive electrode potential verses reference level above a positive electrode damage threshold potential of the cell under the applied load to a near zero cell voltage state.

19. The method of claim 10, further comprising applying a load to the cell based on the capacity of the cell to realize a near zero volt condition during storage, wherein the load is designed for low current dissipation.

20. The method of claim 10, further comprising applying a load to the cell based on the capacity of the cell to realize a near zero volt condition during storage, wherein the load is designed for high current dissipation and the load is coupled to a heat transfer device.