Electrode protection using electrolyte-inhibiting ion conductor

Patent metadata

Field	Value
Publication number	US-11710847-B2
Application number	US-202117503606-A
Country	US
Kind code	B2
Filing date	Oct 18, 2021
Priority date	Feb 19, 2014
Publication date	Jul 25, 2023
Grant date	Jul 25, 2023

Abstract

The use of ion-conducting materials to protect electrodes is generally described. The ion-conducting material may be in the form of a layer that is adjacent to a polymeric layer, such as a porous separator, to form a composite. At least a portion of the pores of the polymer layer may be filled or unfilled with the ion-conducting material. In some embodiments, the ion-conducting layer is sufficiently bonded to the polymer layer to prevent delamination of the layers during cycling of an electrochemical cell.

First claim

What is claimed is:

1. A method of forming a component for an electrochemical cell, comprising:
providing a separator comprising pores having an average pore size and a surface having a first surface energy, and having a bulk electronic resistivity of at least 10 4 Ohm-meters;
increasing the surface energy of the surface of the separator to a second surface energy in a pre-treatment step, wherein the second surface energy is at least 60 dynes; and
depositing an inorganic ion conductor layer on the surface of the separator, wherein the inorganic ion conductor layer has an ion conductivity of at least 10 −6 S/cm, wherein the inorganic ion conductor layer has a thickness of less than or equal to 2 microns, and wherein the separator and the inorganic ion conductor layer form a composite having an air permeation time of at least 20,000 Gurley-s and at most 200,000 Gurley-s according to Gurley test TAPPI Standard T 536 om-12.

2. A method of forming a component for an electrochemical cell, comprising:
providing a separator comprising pores having an average pore size and a surface having a first surface energy, and having a bulk electronic resistivity of at least about 10 4 Ohm-meters;
subjecting the surface of the separator to a plasma in a pre-treatment step; and
depositing an inorganic ion conductor layer on the surface of the separator, wherein the inorganic ion conductor layer has an ion conductivity of at least 10 −6 S/cm, wherein the inorganic ion conductor layer has a thickness of less than or equal to 2 microns, and wherein the separator and the inorganic ion conductor layer form a composite having an air permeation time of at least 20,000 Gurley-s and at most 200,000 Gurley-s according to Gurley test TAPPI Standard T 536 om-12.

3. An electrochemical cell, comprising:
a first electrode comprising a first electroactive material;
a second electrode; and
a separator between the first and second electrodes, comprising pores in which electrolyte can reside, and comprising a region proximate the first electrode in which the pores are substantially filled with an ion conductor that inhibits interaction of electrolyte with the first electroactive material, wherein the separator and the ion conductor form a composite having an air permeation time of at least 20,000 Gurley-s and at most 200,000 Gurley-s according to Gurley test TAPPI Standard T 536 om-12.

4. The method of claim 1 , wherein the inorganic ion conductor layer is deposited by electron beam evaporation or by a sputtering process.

5. The method of claim 1 , wherein the pre-treatment step comprises subjecting the surface of the separator to a plasma in the presence of air, oxygen, ozone, carbon dioxide, carbonyl sulfide, sulfur dioxide, nitrous oxide, nitric oxide, nitrogen dioxide, nitrogen, ammonia, hydrogen, fluorinated carbon compounds, freons, silanes, and/or argon.

6. The method of claim 1 , wherein the pre-treatment step comprises subjecting the surface of the separator to a plasma for at least 1 minute, at least 5 minutes, or at least 10 minutes.

7. The method of claim 1 , wherein the inorganic ion conductor layer is bonded to the separator by covalent bonding.

8. The method of claim 1 , wherein the air permeation time of the composite is at least 40,000 Gurley-s and at most 200,000 Gurley-s.

9. The method of claim 1 , wherein the separator has a thickness between 5 microns and 40 microns.

10. The method of claim 1 , wherein the separator has a bulk electronic resistivity of at least 10 10 Ohm-meters and/or less than or equal to 10 15 Ohm-meters.

11. The method of claim 1 , wherein the separator is a solid, polymeric separator, and wherein the separator comprises one or more of poly(n-pentene-2), polypropylene, polytetrafluoroethylene, a polyamide, and polyether ether ketone (PEEK).

12. The method of claim 1 , wherein the inorganic ion conductor layer comprises an inorganic ion conductor material, and wherein the pores of the separator are substantially unfilled with the inorganic ion conductor material.

13. The method of claim 1 , wherein the inorganic ion conductor layer comprises an inorganic ion conductor material, and wherein at least a portion of the pores of the separator are filled with the inorganic ion conductor material.

14. The method of claim 1 , wherein an average pore size of the separator is less than or equal to 5 microns.

15. The method of claim 1 , wherein the inorganic ion conductor layer comprises a ceramic, a glass, and/or a glass-ceramic, and wherein the inorganic ion conductor layer comprises one or more of a lithium nitride, a lithium silicate, a lithium borate, a lithium aluminate, a lithium phosphate, a lithium phosphorus oxynitride, a lithium borosulfide, a lithium aluminosulfide, a lithium phosphosulfide, and a lithium oxysulfide.

16. The method of claim 1 , wherein a strength of adhesion between the separator and the inorganic ion conductor layer passes the tape test according to the standard ASTM D3359-02.

17. The method of claim 1 , wherein the electrochemical cell comprises an electrolyte, and wherein the separator swells in the electrolyte.

18. The method of claim 1 , wherein the inorganic ion conductor layer comprises a metal oxide of the metal ion conductive in the inorganic ion conductor layer.

19. The method of claim 1 , wherein the electrochemical cell comprises a first electrode comprising lithium metal and/or a lithium metal alloy, and wherein the inorganic ion conductor layer is conductive to lithium ions.

20. The method of claim 1 , wherein the inorganic ion conductor layer serves as a solvent barrier and/or a protective structure within the electrochemical cell.

21. The electrochemical cell of claim 3 , wherein the ion conductor is bonded to the separator by covalent bonding.

22. The electrochemical cell of claim 3 , wherein the air permeation time of the composite is at least 40,000 Gurley-s and at most 200,000 Gurley-s.

23. The electrochemical cell of claim 3 , wherein the separator is a solid, polymeric separator, and wherein the separator comprises one or more of poly(n-pentene-2), polypropylene, polytetrafluoroethylene, a polyamide, and polyether ether ketone (PEEK).

24. The electrochemical cell of claim 3 , wherein an average pore size of the separator is less than or equal to 1 micron.

25. The electrochemical cell of claim 3 , wherein the first electrode comprises lithium metal and/or a lithium metal alloy, and wherein the ion conductor is conductive to lithium ions.

26. The electrochemical cell of claim 3 , wherein a strength of adhesion between the separator and the ion conductor is at least 350 N/m or at least 500 N/m.

27. The electrochemical cell of claim 3 , wherein the ion conductor extends, on average, at least about 25% through the pores of the separator from the side of the separator facing the first electrode, toward the second electrode.

Assignees

• Sion Power Corp

Inventors

• Laramie Michael G
• Mikhaylik Yuriy V
• Kelley Tracy Earl
• Child David
• Scordilis-Kelley Chariclea
• Viner Veronika G
• Sankaran Bala

Classifications

• H01M10/052 Primary

  Li-accumulators · CPC title

• H01M50/414

  Synthetic resins, e.g. thermoplastics or thermosetting resins · CPC title

• H01M50/417

  Polyolefins · CPC title

• H01M50/423

  Polyamide resins · CPC title

• H01M50/426

  Fluorocarbon polymers · CPC title