Method of producing protected particles of anode active materials for lithium batteries
View Patent ↗A method of producing a powder mass for a lithium battery, the method comprising: (a) Providing a solution containing a sulfonated elastomer dissolved in a solvent or a precursor in a liquid form or dissolved in a solvent; (b) dispersing a plurality of particles of an anode active material in the solution to form a slurry; and (c) dispensing the slurry and removing the solvent and/or polymerizing/curing the precursor to form the powder mass, wherein the powder mass comprises multiple particulates and at least a particulate is composed of one or a plurality of particles of an anode active material being encapsulated by a thin layer of sulfonated elastomer having a thickness from 1 nm to 10 μm, a fully recoverable tensile strain from 2% to 800%, and a lithium ion conductivity from 10 −7 S/cm to 5×10 −2 S/cm at room temperature.
1. A method of producing a powder mass of an anode active material for a lithium battery, said method comprising:
(a) providing a solution containing a sulfonated elastomer dissolved in a solvent or a precursor (monomer or oligomer) to said sulfonated elastomer in a liquid form or dissolved in a solvent; wherein said sulfonated elastomer contains a material selected from sulfonated natural polyisoprene, sulfonated synthetic polyisoprene, sulfonated polybutadiene, sulfonated chloroprene rubber, sulfonated polychloroprene, sulfonated butyl rubber, sulfonated styrene-butadiene rubber, sulfonated nitrile rubber, sulfonated ethylene propylene rubber, sulfonated ethylene propylene diene rubber, sulfonated metallocene-based poly(ethylene-co-octene) elastomer, sulfonated poly(ethylene-co-butene) elastomer, sulfonated styrene-ethylene-butadiene-styrene elastomer, sulfonated epichlorohydrin rubber, sulfonated polyacrylic rubber, sulfonated silicone rubber, sulfonated fluorosilicone rubber, sulfonated perfluoroelastomers, sulfonated polyether block amides, sulfonated chlorosulfonated polyethylene, sulfonated ethylene-vinyl acetate polymer, sulfonated protein resilin, sulfonated protein elastin, sulfonated ethylene oxide-epichlorohydrin copolymer, sulfonated polyurethane, sulfonated urethane-urea copolymer, or a combination thereof;
(b) dispersing a plurality of particles of an anode active material in said solution to form a slurry; and
(c) dispensing said slurry and removing said solvent and/or polymerizing/curing said precursor to form said powder mass, wherein said powder mass comprises multiple particulates wherein at least a particulate is composed of one or a plurality of particles of an anode active material being encapsulated by a thin layer of sulfonated elastomer having a thickness from 1 nm to 10 μm, a fully recoverable tensile strain from 2% to 800%, and a lithium ion conductivity from 10 −7 S/cm to 5×10 −2 S/cm at room temperature.
2. The method of claim 1 , wherein said step of dispensing said slurry and removing said solvent and/or polymerizing/curing said precursor to form said powder mass includes operating a procedure selected from pan-coating, air-suspension coating, centrifugal extrusion, vibration-nozzle encapsulation, spray-drying, coacervation-phase separation, interfacial polycondensation and interfacial cross-linking, in-situ polymerization, matrix polymerization, or a combination thereof.
3. The method of claim 1 , wherein said step of providing said solution includes (a) sulfonating an elastomer to form said sulfonated elastomer and dissolving said sulfonated elastomer in said solvent to form said solution, or (b) sulfonating said precursor to obtain a sulfonated precursor (sulfonated monomer or sulfonated oligomer), polymerizing said sulfonated precursor to form said sulfonated elastomer and dissolving said sulfonated elastomer in said solvent to form said solution.
4. The method of claim 1 , wherein said anode active material is selected from the group consisting of: (a) silicon (Si), germanium (Ge), tin (Sn), lead (Pb), antimony (Sb), bismuth (Bi), zinc (Zn), aluminum (Al), titanium (Ti), nickel (Ni), cobalt (Co), and cadmium (Cd); (b) alloys or intermetallic compounds of Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, Ti, Ni, Co, or Cd with other elements; (c) oxides, carbides, nitrides, sulfides, phosphides, selenides, and tellurides of Si, Ge, Sn, Pb, Sb, Bi, Zn, Al, Ti, Fe, Ni, Co, V, or Cd, and their mixtures, composites, or lithium-containing composites; (d) salts and hydroxides of Sn; (e) lithium titanate, lithium manganate, lithium aluminate, lithium-containing titanium oxide, lithium transition metal oxide; (f) prelithiated versions thereof; (g) particles of Li, Li alloy, or surface-stabilized Li having at least 60% by weight of lithium element therein; and (h) combinations thereof.
5. The method of claim 1 , wherein said anode active material contains a prelithiated Si, prelithiated Ge, prelithiated Sn, prelithiated SnO x , prelithiated SiO x , prelithiated iron oxide, prelithiated VO 2 , prelithiated Co 3 O 4 , prelithiated Ni 3 O 4 , or a combination thereof, wherein 1≤x≤2.
6. The method of claim 1 , wherein said anode active material is in a form of nanoparticle, nanowire, nanofiber, nanotube, nanosheet, nanobelt, nanoribbon, nanodisc, nanoplatelet, or nanohorn having a thickness or diameter from 0.5 nm to 100 nm.
7. The method of claim 1 , wherein one or a plurality of said anode active material particles is coated with a layer of carbon prior to step (b).
8. The method of claim 1 , wherein said slurry further contains a graphite or carbon material selected from polymeric carbon, amorphous carbon, chemical vapor deposition carbon, coal tar pitch, petroleum pitch, mesophase pitch, carbon black, coke, acetylene black, activated carbon, fine expanded graphite particle with a dimension smaller than 100 nm, artificial graphite particle, natural graphite particle, or a combination thereof.
9. The method of claim 1 , wherein said step (a) further includes dissolving or dispersing from 0.1% to 40% by weight of a lithium ion-conducting additive in said solution.
10. The method of claim 9 , wherein said lithium ion-conducting additive is selected from Li 2 CO 3 , Li 2 O, Li 2 C 2 O 4 , LiOH, LiX, ROCO 2 Li, HCOLi, ROLi, (ROCO 2 Li) 2 , (CH 2 OCO 2 Li) 2 , Li 2 S, Li x SO y , or a combination thereof, wherein X=F, Cl, I, or Br, R=a hydrocarbon group, 0≤x≤1, 1≤y≤4.
11. The method of claim 9 , wherein said lithium ion-conducting additive contains a lithium salt selected from lithium perchlorate (LiClO 4 ), lithium hexafluorophosphate (LiPF 6 ), lithium borofluoride (LiBF 4 ), lithium hexafluoroarsenide (LiAsF 6 ), lithium trifluoro-metasulfonate, (LiCF 3 SO 3 ), bis-trifluoromethyl sulfonylimide lithium (LiN(CF 3 SO 2 ) 2 ), lithium bis(oxalato)borate (LiBOB), lithium oxalyldifluoroborate (LiBF 2 C 2 O 4 ), lithium oxalyldifluoroborate (LiBF 2 C 2 O 4 ), lithium nitrate (LiNO 3 ), Li-fluoroalkyl-phosphates, (LiPF 3 (CF 2 CF 3 ) 3 ), lithium bisperfluoro-ethysulfonylimide (LiBETI), lithium bis(trifluoromethanesulphonyl)imide, lithium bis(fluorosulphonyl)imide, lithium trifluoromethanesulfonimide (LiTFSI), an ionic liquid-based lithium salt, or a combination thereof.
12. The method of claim 1 , wherein said slurry further contains an electron-conducting polymer selected from polyaniline, polypyrrole, polythiophene, polyfuran, a bi-cyclic polymer, a sulfonated derivative thereof, or a combination thereof.
13. The method of claim 1 , wherein said slurry further contains a lithium ion-conducting polymer selected from poly(ethylene oxide) (PEO), polypropylene oxide (PPO), poly(acrylonitrile) (PAN), poly(methyl methacrylate) (PMMA), poly(vinylidene fluoride) (PVDF), poly bis-methoxy ethoxyethoxide-phosphazenes, polyvinyl chloride, polydimethylsiloxane, poly(vinylidene fluoride)-hexafluoropropylene (PVDF-HFP), a sulfonated derivative thereof, or a combination thereof.
14. The method of claim 1 , wherein said high-capacity anode active material is prelithiated to contains from 0.1% to 54.7% by weight of lithium prior to step (b).
15. The method of claim 1 , wherein said sulfonated elastomer is obtained by exposing an elastomer to a treatment selected from (i) exposure to sulfur trioxide in vapor phase or in solution, optionally in presence of Lewis bases such as triethyl phosphate, tetrahydrofuran, dioxane, or amines; (ii) exposure to chlorosulfonic acid in diethyl ether; (iii) exposure to concentrated sulfuric acid or a mixture of sulfuric acid with alkyl hypochlorite; (iv) exposure to a bisulfite combined to dioxygen, hydrogen peroxide, metallic catalysts, or peroxo derivates; (v) exposure to acetyl sulfate; or a combination thereof.
16. A method of producing a sulfonated powder mass of an anode active material for a lithium battery, said method comprising:
(A) providing a solution containing an elastomer dissolved in a solvent or an precursor to said elastomer in a liquid form or dissolved in a solvent; wherein the elastomer is a sulfonated elastomer containing a material selected from sulfonated natural polyisoprene, sulfonated synthetic polyisoprene, sulfonated polybutadiene, sulfonated chloroprene rubber, sulfonated polychloroprene, sulfonated butyl rubber, sulfonated styrene-butadiene rubber, sulfonated nitrile rubber, sulfonated ethylene propylene rubber, sulfonated ethylene propylene diene rubber, sulfonated metallocene-based poly(ethylene-co-octene) elastomer, sulfonated poly(ethylene-co-butene) elastomer, sulfonated styrene-ethylene-butadiene-styrene elastomer, sulfonated epichlorohydrin rubber, sulfonated polyacrylic rubber, sulfonated silicone rubber, sulfonated fluorosilicone rubber, sulfonated perfluoroelastomers, sulfonated polyether block amides, sulfonated chlorosulfonated polyethylene, sulfonated ethylene-vinyl acetate polymer, sulfonated protein resilin, sulfonated protein elastin, sulfonated ethylene oxide-epichlorohydrin copolymer, sulfonated polyurethane, sulfonated urethane-urea copolymer, or a combination thereof;
(B) dispersing a plurality of particles of an anode active material in said solution to form a slurry;
(C) dispensing said slurry and removing said solvent and/or polymerizing/curing said precursor to form a powder mass, wherein said powder mass comprises multiple particulates wherein at least a particulate is composed of one or a plurality of particles of an anode active material being encapsulated by a thin layer of elastomer having a thickness from 1 nm to 10 μm; and
(D) sulfonating said thin layer of elastomer by exposing said powder mass to a sulfonating agent to form said sulfonated powder mass containing sulfonated elastomer-encapsulated particles, wherein sulfonated elastomer has a fully recoverable tensile strain from 2% to 800%, and a lithium ion conductivity from 10 −7 S/cm to 5×10 −2 S/cm at room temperature.
17. The method of claim 16 , wherein said sulfonating agent is selected from sulfuric acid, sulfonic acid, sulfur trioxide, chlorosulfonic acid, a bisulfate, a sulfate, or a mixture thereof.
18. The method of claim 1 , further comprising mixing multiple particulates of said anode active material, a binder resin, and an optional conductive additive to form an anode active material layer, which is optionally coated on an anode current collector.
19. The method of claim 18 , further comprising combining said anode active material layer, a cathode layer, an electrolyte, and an optional porous separator into a lithium battery cell.