Method of producing a shape-conformable alkali metal battery having a conductive and deformable quasi-solid polymer electrode

Patent metadata

Field	Value
Publication number	US-10170789-B2
Application number	US-201715610136-A
Country	US
Kind code	B2
Filing date	May 31, 2017
Priority date	May 31, 2017
Publication date	Jan 1, 2019
Grant date	Jan 1, 2019

Abstract

Provided is method of preparing an alkali metal cell, the method comprising: (a) combining a quantity of an active material, a quantity of an electrolyte, and a conductive additive to form a deformable and conductive electrode material, wherein the conductive additive, containing conductive filaments, forms a 3D network of electron-conducting pathways and the electrolyte contains an alkali salt and an ion-conducting polymer dissolved or dispersed in a solvent; (b) forming the electrode material into a quasi-solid polymer electrode, wherein the forming includes deforming the electrode material into an electrode shape without interrupting the 3D network of electron-conducting pathways such that the electrode maintains an electrical conductivity no less than 10 −6 S/cm; (c) forming a second electrode; and (d) forming an alkali metal cell by combining the quasi-solid electrode and the second electrode. The second electrode may also be a quasi-solid polymer electrode.

First claim

We claim:

1. A method of preparing an alkali metal cell having a quasi-solid electrode, the method comprising:
(a) combining a quantity of an active material, a quantity of an electrolyte, and a conductive additive to form a deformable and electrically conductive electrode material, wherein said conductive additive, containing conductive filaments, forms a 3D network of electron-conducting pathways and said electrolyte contains an alkali salt and an ion-conducting polymer dissolved or dispersed in a solvent;
(b) forming the electrode material into a quasi-solid electrode, wherein said forming includes deforming the electrode material into an electrode shape without interrupting said 3D network of electron-conducting pathways such that the electrode maintains an electrical conductivity no less than 10 −6 S/cm;
(c) forming a second electrode; and
(d) forming an alkali metal cell by combining the quasi-solid electrode and the second electrode.

2. The method of claim 1 , wherein said quasi-solid electrode contains 30% to 95% by volume of said active material, 5% to 40% by volume of said electrolyte, and 0.01% to 30% by volume of said conductive additive.

3. The method of claim 1 , wherein said electrolyte contains a quasi-solid polymer electrolyte containing an ion-conducting polymer selected from poly(ethylene oxide) (PEO) having a molecular weight lower than 1×10 6 g/mole, polypropylene oxide (PPO), poly(acrylonitrile) (PAN), poly(methyl methacrylate) (PMMA), poly(vinylidene fluoride) (PVdF), poly bis-methoxy ethoxyethoxide-phosphazene, polyvinyl chloride, polydimethylsiloxane, poly(vinylidene fluoride)-hexafluoropropylene (PVDF-HFP), a sulfonated derivative thereof, a sulfonated polymer, or a combination thereof.

4. The method of claim 1 , wherein said ion-conducting polymer is selected from the group consisting of poly(perfluoro sulfonic acid), sulfonated polytetrafluoroethylene, sulfonated perfluoroalkoxy derivatives of polytetrafluoroethylene, sulfonated polysulfone, sulfonated poly(ether ketone), sulfonated poly (ether ether ketone), sulfonated polystyrene, sulfonated polyimide, sulfonated styrene-butadiene copolymers, sulfonated poly chloro-trifluoroethylene (PCTFE), sulfonated perfluoroethylene-propylene copolymer (FEP), sulfonated ethylene-chlorotrifluoroethylene copolymer (ECTFE), sulfonated polyvinylidenefluoride (PVDF), sulfonated copolymers of polyvinylidenefluoride with hexafluoropropene and tetrafluoroethylene, sulfonated copolymers of ethylene and tetrafluoroethylene (ETFE), sulfonated polybenzimidazole (PBI), their chemical derivatives, copolymers, blends and combinations thereof.

5. The method of claim 1 , wherein said conductive filaments are selected from carbon fibers, graphite fibers, carbon nanofibers, graphite nanofibers, carbon nanotubes, needle coke, carbon whiskers, conductive polymer fibers, conductive material-coated fibers, metal nanowires, metal fibers, metal wires, graphene sheets, expanded graphite platelets, a combination thereof, or a combination thereof with non-filamentary conductive particles.

6. The method of claim 1 , wherein said ion-conducting polymer does not form a matrix in said quasi-solid cathode.

7. The method of claim 1 , wherein said electrode maintains an electrical conductivity from 10 −3 S/cm to 10 S/cm.

8. The method of claim 1 , wherein said quasi-solid cathode contains 0.1% to 20% by volume of a conductive additive.

9. The method of claim 1 , wherein said quasi-solid cathode contains 1% to 10% by volume of a conductive additive.

10. The method of claim 1 , wherein the quantity of the active material is 40% to 90% by volume of the electrode material.

11. The method of claim 1 , wherein the quantity of the active material is 50% to 85% by volume of the electrode material.

12. The method of claim 1 , wherein said step of combining includes dispersing said conductive filaments into a liquid solvent to form a homogeneous suspension prior to adding said active material in said suspension and prior to dissolving said alkali metal salt and said ion-conducting polymer in said liquid solvent of said suspension.

13. The method of claim 1 , wherein said steps of combining and forming the electrode material into a quasi-solid electrode include dissolving a lithium salt or sodium salt and said polymer in a liquid solvent to form an electrolyte having a first salt/polymer concentration and subsequently removing portion of said liquid solvent to increase the salt/polymer concentration to obtain a quasi-solid polymer electrolyte having a second salt/polymer concentration higher than the first concentration and higher than 2.5 M.

14. The method of claim 12 , wherein said removing does not cause precipitation or crystallization of said salt or said polymer, and said electrolyte is in a supersaturated state.

15. The method of claim 12 , wherein said liquid solvent contains a mixture of at least a first liquid solvent and a second liquid solvent and the first liquid solvent is more volatile than the second liquid solvent and wherein said removing portion of said liquid solvent includes removing said first liquid solvent.

16. The method of claim 1 , wherein said step of forming a second electrode includes (A) combining a quantity of a second active material, a quantity of an electrolyte, and a conductive additive to form a second deformable and electrically conductive electrode material, wherein said conductive additive, containing conductive filaments, forms a 3D network of electron-conducting pathways and said electrolyte contains an alkali salt and an ion-conducting polymer dissolved or dispersed in a solvent; and (B) forming the second deformable and conductive electrode material into a second quasi-solid electrode, wherein said forming includes deforming the second deformable and conductive electrode material into an electrode shape without interrupting said 3D network of electron-conducting pathways such that the second electrode maintains an electrical conductivity no less than 10 −6 S/cm.

17. The method of claim 1 , wherein said solvent is selected from water, an organic solvent, an ionic liquid, or a mixture of an organic solvent and an ionic liquid.

18. The method of claim 1 , wherein said alkali metal cell is a lithium metal cell, lithium-ion cell, or lithium-ion capacitor cell and said active material is an anode active material selected from the group consisting of:
(a) particles of lithium metal or a lithium metal alloy;
(b) natural graphite particles, artificial graphite particles, mesocarbon microbeads (MCMB), carbon particles, needle coke, carbon nanotubes, carbon nanofibers, carbon fibers, and graphite fibers;
(c) silicon (Si), germanium (Ge), tin (Sn), lead (Pb), antimony (Sb), bismuth (Bi), zinc (Zn), aluminum (Al), nickel (Ni), cobalt (Co), manganese (Mn), titanium (Ti), iron (Fe), and cadmium (Cd);
(d) alloys or intermetallic compounds of Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, or Cd with other elements, wherein said alloys or compounds are stoichiometric or non-stoichiometric;
(e) oxides, carbides, nitrides, sulfides, phosphides, selenides, and tellurides of Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, Fe, Ni, Co, Ti, Mn, or Cd, and their mixtures or composites;
(f) prelithiated versions thereof;
(g) prelithiated graphene sheets; and
combinations thereof.

19. The method of claim 18 , wherein said prelithiated graphene sheets are selected from prelithiated versions of pristine graphene, graphene oxide, reduced graphene oxide, graphene fluoride, graphene chloride, graphene bromide, graphene iodide, hydro

Assignees

• Nanotek Instruments Inc

Inventors

• Zhamu Aruna
• Jang Bor Z

Classifications

• H01G11/44

  Raw materials therefor, e.g. resins or coal · CPC title

• H01G11/46

  Metal oxides · CPC title

• H01G11/60

  characterised by the solvent · CPC title

• H01M10/0565

  Polymeric materials, e.g. gel-type or solid-type · CPC title

• H01G11/06

  with one of the electrodes allowing ions to be reversibly doped thereinto, e.g. lithium ion capacitors [LIC] · CPC title