Surface modification agents for lithium batteries

1. A method of modifying a surface of an electrode active material, the method comprising:

providing a solution or a suspension of a surface modification agent;

providing the electrode active material;

preparing a slurry of the solution or suspension of the surface modification agent, the electrode active material, a polymeric binder, and a conductive filler;

casting the slurry on a metallic current collector; and

drying the cast slurry;

wherein:

the surface modification agent is a compound selected from the group consisting of aluminum sec-butoxide, diethylaluminum ethoxide, tris(ethylmethylamido)aluminum, triethylaluminum, triisobutylaluminum, trimethylaluminum, tris(diethylamido)aluminum, trimethylarsine, diborane, trimethylboron, bis(N,N′-diisopropylacetaminato)cobalt (II), dicarbonyl(cyclopentadienyl)cobalt (I), (N,N′-diisopropylacetaminato)copper (II), bis(N,N′-di-tert-butylacetamidinato)iron (II), gallium tribromide, gallium trichloride, triethylgallium, triisopropylgallium, trimethylgallium, tri(dimethylamido)gallium, tri-tert-butylgallium, digermane, germane, tetramethylgermanium, hafnium (IV) chloride, hafnium (IV) tert-butoxide, tetrakis(diethylamido)hafnium (IV), tetrakis(dimethylamido)hafnium (IV), tetrakis(ethylmethylamido)hafnium (IV), indium trichloride, indium(I) iodide, indium acetylacetonate, triethylindium, tris(N,N′-Di-tert-butylacetamidinato)lanthanum (III), bis(pentaethylcyclopentadienyl)magnesium, molybdenum hexacarbonyl, N,N-dimethylhydrazine, niobium (V) ethoxide, bis(methyl-cyclopentadienyl)nickel (II), phosphine, tert-butylphosphine, cyclopentadienyl(trimethyl)platinum (IV), bis(ethylcyclopentadienyl) ruthenium (II), trimethylantimony, tris(dimethylamido) antimony, pentakis(dimethylamido)tantalum (V), tantalum (V) chloride, tantalum (V) ethoxide, tris(diethylamino)(tert-butylimido)tantalum (V), bis(diethylamido)bis(dimethylamido) titanium (IV), tetrakis(diethylamido)titanium (IV), tetrakis(dimethylamido)titanium (IV), tetrakis(ethylmethylamido)titanium (IV), titanium (IV) tert-butoxide, vanadium (V) oxytriisopropoxide, bis(tert-butylimido)bis(dimethylamido)tungsten (VI), tungsten hexacarbonyl, tungsten (VI) chloride, yttrium (III) butoxide, diethylzinc, tetrakis(diethylamido)zirconium (IV), tetrakis(dimethylamido)zirconium (IV), tetrakis(ethylmethylamido)zirconium (IV), zirconium (IV) tert-butoxide, and a mixture of any two or more thereof.

2. The method of claim 1 , wherein the polymeric binder is polyvinylidene difluoride, copolymer of polyvinylidene difluoride and hexafluoropropylene, or a mixture thereof.

3. The method of claim 1 , wherein the conductive filler is carbon black, carbon fiber, graphite, a metallic nano powder, or a mixture of any two or more thereof.

4. The method of claim 1 , wherein the concentration of the surface modification agent in the slurry is from about 0.00001 wt% to 5 wt%.

5. The method of claim 1 , wherein the electrode active material is a positive electrode active material selected from the group consisting of spinel, olivine, carbon-coated olivine, LiFePO 4 , Li x′ M′ y′ M″ z′ PO 4 , Li 1+x″ Ni α Mn β Co γ Met′ δ O 2−z″ F z″ , A n″ B 2 (XO 4 ) 3 , vanadium oxide, and mixtures of any two or more thereof; and further wherein

M′ is selected from the group consisting of V, Cr, Mg, Fe, Co, and Ni;

M″ is selected from group consisting of IIA, IIIA, IVA, VA, VIA and IIIB metals having an ionic radius less than the ionic radius of Fe 2+ ;

Met′ is selected from the group consisting of Mg, Zn, Al, Ga, B, Zr, and Ti; and

0≦x′≦1, 0≦y′≦1, 0≦z′≦1, 0≦x″≦0.4, 0≦α≦1, 0≦β≦1, 0≦γ≦2, 0≦δ≦0.2, 0≦z″≦0.5, and 0≦n″≦3.

6. The method of claim 1 , wherein the electrode active material is a negative electrode material selected from the group consisting of graphite, amorphous carbon, Li 4 Ti 5 O 12 , M 1−x A x Li 2−y B y Ti 6−z C z O 14−t Q t , tin alloys, silicon alloys, intermetallic compounds, lithium metal, or mixtures of any two or more such materials; and further wherein:

M is selected from the group consisting of Ba, Sr, Ca, Mg, Pb, and Sn;

0≦x≦0.5, 0≦y≦0.5, 0≦z≦0.5, 0<t≦0.5;

each of A, B and C are independently at least one divalent, trivalent or tetravalent metal; and

Q is a monovalent or divalent anion.

7. The method of claim 1 , wherein the surface modification agent is a compound selected from the group consisting of aluminum sec-butoxide, diethylaluminum ethoxide, tris(ethylmethylamido)aluminum, triethylaluminum, triisobutylaluminum, trimethylaluminum, tris(diethylamido)aluminum, trimethylarsine, diborane, trimethylboron, bis(N,N′-diisopropylacetaminato)cobalt (II), dicarbonyl(cyclopentadienyl)cobalt (I), (N,N′-diisopropylacetaminato)copper (II), bis(N,N′-di-tert-butylacetamidinato)iron (II), gallium tribromide, gallium trichloride, triethylgallium, triisopropylgallium, trimethylgallium, tri(dimethylamido)gallium, tri-tert-butylgallium, digermane, germane, tetramethylgermanium, hafnium (IV) chloride, hafnium (IV) tert-butoxide, tetrakis(diethylamido)hafnium (IV), tetrakis(dimethylamido)hafnium (IV), tetrakis(ethylmethylamido)hafnium (IV), indium trichloride, indium(I) iodide, indium acetylacetonate, triethylindium, tris(N,N′-Di-tert-butylacetamidinato)lanthanum (III), bis(pentaethylcyclopentadienyl)magnesium, molybdenum hexacarbonyl, niobium (V) ethoxide, bis(methyl-cyclopentadienyl)nickel (II), cyclopentadienyl(trimethyl)platinum (IV), bis(ethylcyclopentadienyl) ruthenium (II), trimethylantimony, tris(dimethylamido) antimony, pentakis(dimethylamido)tantalum (V), tantalum (V) chloride, tantalum (V) ethoxide, tris(diethylamino)(tert-butylimido)tantalum (V), bis(diethylamido)bis(dimethylamido) titanium (IV), tetrakis(diethylamido)titanium (IV), tetrakis(dimethylamido)titanium (IV), tetrakis(ethylmethylamido)titanium (IV), titanium (IV) tert-butoxide, vanadium (V) oxytriisopropoxide, bis(tert-butylimido)bis(dimethylamido)tungsten (VI), tungsten hexacarbonyl, tungsten (VI) chloride, yttrium (III) butoxide, diethylzinc, tetrakis(diethylamido)zirconium (IV), tetrakis(dimethylamido)zirconium (IV), tetrakis(ethylmethylamido)zirconium (IV), zirconium (IV) tert-butoxide, and a mixture of any two or more thereof.

8. A method of modifying a surface of an electrode active material, the method comprising:

providing a solution or a suspension of a surface modification agent;

providing the electrode active material;

preparing a slurry of the solution or suspension of the surface modification agent, the electrode active material, a polymeric binder, and a conductive filler;

casting the slurry on a metallic current collector; and

drying the cast slurry;

wherein:

the surface modification agent is a compound selected from the group consisting of aluminum sec-butoxide, diethylaluminum ethoxide, tris(ethylmethylamido)aluminum, triethylaluminum, triisobutylaluminum, trimethylaluminum, tris(diethylamido)aluminum, trimethylarsine, diborane, trimethylboron, bis(N,N′-diisopropylacetaminato)cobalt (II), dicarbonyl(cyclopentadienyl)cobalt (I), (N,N′-diisopropylacetaminato)copper (II), bis(N,N′-di-tert-butylacetamidinato)iron (II), gallium tribromide, gallium trichloride, triethylgallium, triisopropylgallium, trimethylgallium, tri(dimethylamido)gallium, tri-tert-butylgallium, digermane, germane, tetramethylgermanium, hafnium (IV) chloride, hafnium (IV) tert-butoxide, tetrakis(diethylamido)hafnium (IV), tetrakis(dimethylamido)hafnium (IV), tetrakis(ethylmethylamido)hafnium (IV), indium trichloride, indium(I) iodide, indium acetylacetonate, triethylindium, tris(N,N′-Di-tert-butylacetamidinato) lanthanum (III), bis(pentaethylcyclopentadienyl)magnesium, molybdenum hexacarbonyl, N,N-dimethylhydrazine, niobium (V) ethoxide, bis(methyl-cyclopentadienyl)nickel (II), phosphine, tert-butylphosphine, cyclopentadienyl(trimethyl)platinum (IV), bis(ethylcyclopentadienyl) ruthenium (II), trimethylantimony, tris(dimethylamido) antimony, pentakis(dimethylamido)tantalum (V), tantalum (V) chloride, tantalum (V) ethoxide, tris(diethylamino)(tert-butylimido)tantalum (V), bis(diethylamido)bis(dimethylamido) titanium (IV), tetrakis(diethylamido)titanium (IV), tetrakis(dimethylamido)titanium (IV), tetrakis(ethylmethylamido)titanium (IV), titanium (IV) tert-butoxide, vanadium (V) oxytriisopropoxide, bis(tert-butylimido)bis(dimethylamido)tungsten (VI), tungsten hexacarbonyl, tungsten (VI) chloride, tungsten (VI) fluoride, yttrium (III) butoxide, diethylzinc, tetrakis(diethylamido)zirconium (IV), tetrakis(dimethylamido)zirconium (IV), tetrakis(ethylmethylamido)zirconium (IV), zirconium (IV) tert-butoxide, and a mixture of any two or more thereof and

the electrode active material is a positive electrode active material selected from the group consisting of spinel, olivine, carbon-coated olivine, LiFePO 4 , Li x′ M′ y′ M″ z′ PO 4 , Li 1+x″ Ni α Mn β Co γ Met′ δO 2−z″ F z″ , A n″ B 2 (XO 4 ) 3 , vanadium oxide, and mixtures of any two or more thereof;

wherein

M′ is selected from the group consisting of V, Cr, Mg, Fe, Co, and Ni;

M″ is selected from group consisting of IIA, IIIA, IVA, VA, VIA and IIIB metals having an ionic radius less than the ionic radius of Fe 2+ ;

Met′ is selected from the group consisting of Mg, Zn, Al, Ga, B, Zr, and Ti; and

0≦x′≦1, 0≦y′≦1, 0≦z′≦1,0≦x″≦0.4, 0≦α≦1, 0≦β≦1, 0≦γ≦2, 0≦δ≦0.2, 0≦z″≦0.5, and 0≦n″≦3.

9. The method of claim 8 , wherein the polymeric binder is polyvinylidene difluoride, copolymer of polyvinylidene difluoride and hexafluoropropylene, or a mixture thereof

10. The method of claim 8 , wherein the conductive filler is carbon black, carbon fiber, graphite, a metallic nano powder, or a mixture of any two or more thereof.

11. The method of claim 8 , wherein the concentration of the surface modification agent in the slurry is from about 0.00001 wt% to 5 wt%.