received by the International Bureau on 01 February 2017 (01.02.2017)

WHAT IS CLAIMED IS:

1. A method for sintering a green tape, the method comprising:

(a) providing at least one source powder, wherein the at least one source powder is selected from the group consisting of lithium- stuffed garnet, chemical precursors to lithium- stuffed garnet, and lithium stuffed garnet with aluminum oxide dopants;

(b) modifying the at least one source powder to prepare a modified source powder;

(c) providing a slurry of the modified source powder;

(d) casting the slurry to form a green tape;

(e) drying the green tape; and

(f) sintering the green tape.

2. The method of claim 1, wherein there amount of source powder in the green tape is at least 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, or 90% by weight.

3. The method of claim 2, wherein the amount of source powder in the green tape is at least 60% or at least 70% by weight.

4. The method any one of claim 1 to 3, wherein the at least one source powder is a

powder of a lithium- stuffed garnet.

5. The method any one of claim 1 to 4, wherein the at least one source powder is

Li₇.iZr2La3Oi2+0.5Al₂O3.

6. The method any one of claim 1 to 4, wherein the at least one source powder is

lithium- stuffed garnet.

7. The method of any one of claims 1 to 4, wherein the modifying the at least one source powder comprises modifying the at least one source powder to having a particle size distribution.

8. The method of claim 8, wherein the particle size distribution is centered around 100 nm, 200 nm, 300 nm, 400 nm, Ιμπι, 2 μπι, 3 μπι, or 4 μπι.

9. The method of claim 8, wherein the particle size distribution is centered around 0.1 to 1 μπι.

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10. The method of any one of claims 1 to 10, wherein the modifying the at least one source powder comprises milling the at least one source powder.

11. The method of any one of claims 1 to 11, wherein the modifying the at least one source powder comprises increasing the surface area of the at least one source powder.

12. The method of claim 11, wherein the milling is selected from the group consisting of dry milling, attrition milling, sonication milling, high energy milling, wet milling, jet milling, and cryogenic milling.

13. The method of claim 11, wherein the milling comprises using a solvent selected from isopropanol or butanol.

14. The method of claim 11, wherein the milling comprises using a solvent selected from methyl- ethyl ketone (MEK) or toluene.

15. The method of claim 11, wherein the milling comprises using a solvent comprises methyl-ethyl ketone (MEK).

16. The method of claim 16, wherein the solvent further comprises isopropanol (IP A).

17. The method of claim 17, wherein the solvent further comprises cyclohexanone.

18. The method of any one of claims 15 - 18, wherein the ratio of MEKTPA is 8:2, 7:3, 6:4, 5:5, 4:6, 3 :7, or 2:8 w/w.

19. The method of any one of claims 17 - 18, wherein the amount of cyclohexanone is about 10-25 % by weight.

20. The method of any one of claims 15 - 20, wherein the solvent is an azeotrope.

21. The method of any one of claim 11 to 20, wherein the surface area of the at least one source powder is increased to at least 3 m²/g during the modifying the at least one source powder.

22. The method of claim 22, wherein the surface area of the at least one source powder is increased to at least 5 m²/g during the modifying the at least one source powder.

23. The method of claim 22, wherein the surface area of the at least one source powder is increased to at least 8 m²/g and less than 15 m²/g during the modifying the at least one source powder.

24. The method of any one of claims 1 to 24, wherein the modifying the at least one

source powder comprises decreasing an average particle size of particles of the at least one source powder.

25. The method of claim 13, wherein the milling is wet milling or high energy milling.

26. The method of claim 13, wherein the milling comprises using a solvent selected from the group consisting of aprotic solvents, organic solvents, solvents which do not proton exchange Li in a lithium- stuffed garnet, and combinations thereof.

27. The method of claim 13, wherein the milling comprises using a solvent selected from the group consisting of methanol, ethanol, propanol, isopropanol, butanol, isobutanol, t-butanol, pentanol, hexanol, cyclohexanol, cyclohexanone, methyl acetate, ethyl acetate, methyl-ethyl ketone (MEK), acetone, toluene, hexanes, acetic acid, and combinations thereof.

28. The method of any one of claims 1 to 28, wherein the modified source powder has a particle size distribution with a d₅o particle size of 100 nm - 200 nm, 200 nm - 300 nm, 300 nm - 400 nm, 400 nm - 500 nm, 500 nm - 600 nm, 600 nm - 700 nm, 700 nm - 800 nm, 800 nm - 900 nm, 900 nm - 1000 nm, 1000 nm - 1 lOOnm, 2000 nm - 2200nm, 3000 nm - 3300nm, or 4000 nm - 4400nm.

29. The method of any one of claims 1 to 28, wherein the modified source powder has a particle size distribution with a d₅o particle size of 100 nm - 200 nm, 200 nm - 300 nm, 300 nm - 400 nm, 400 nm - 500 nm, 500 nm - 600 nm, 600 nm - 700 nm, 700 nm - 800 nm, 800 nm - 900 nm, or 900 nm - 1000 nm.

30. The method of claim 30, wherein the d₅o is 100 nm - 200 nm, 200 nm - 300 nm, or 300 nm - 400 nm

31. The method of any one of claims 1 to 31, further comprising stress relieving the green tape prior to the sintering.

32. The method of any one of claims 1 to 32, further comprising laminating more than one green tape together.

33. The method of any one of claims 1 to 32, further comprising laminating one green tape on to a second green tape.

34. The method of any one of claims 1 to 32, further comprising, prior to step (d), mixing with the slurry of the modified source powder, a binder selected from the group consisting of polypropylene (PP), atactic polypropylene (aPP), isotactic

polypropylene (iPP), polyvinyl butyral (PVB), acrylic, poly ethyl methacrylate (PMMA), poly ethyl methacrylate (PEMA), polyvinyl pyrrolidone (PVP), atactic polypropylene (aPP), isotactive polypropylene ethylene propylene rubber (EPR), ethylene pentene copolymer (EPC), polyisobutylene (PIB), styrene butadiene rubber (SBR), polyolefins, polyethylene-copoly- 1-octene (PE-co-PO); PE-co- poly(methylene cyclopentane) (PE-co-PMCP); stereo block polypropylenes, polypropylene polymethylpentene copolymer, poly propylene carbonate, methyl methacrylate, ethyl methacrylate, silicone, and combinations thereof.

35. The method of any one of claims 1 to 35, wherein the slurry comprises a binder

selected from the group consisting of polypropylene (PP), atactic polypropylene (aPP), isotactic polypropylene (iPP), polyvinyl butyral (PVB), acrylic, poly ethyl methacrylate (PMMA), poly ethyl methacrylate (PEMA), polyvinyl pyrrolidone (PVP), atactic polypropylene (aPP), isotactive polypropylene ethylene propylene rubber (EPR), ethylene pentene copolymer (EPC), polyisobutylene (PIB), styrene butadiene rubber (SBR), polyolefins, polyethylene-copoly- 1-octene (PE-co-PO); PE- co-poly(methylene cyclopentane) (PE-co-PMCP); stereo block polypropylenes, polypropylene polymethylpentene copolymer, poly propylene carbonate, methyl methacrylate, ethyl methacrylate, silicone, and combinations thereof.

36. The method of any one of claims 1 to 36, wherein the at least one source powder is a Li-stuffed garnet compound characterized by the formula Li_xLa_yZr_zO_t qAl₂03, wherein 4<x< 10, Ky<4, Kz<3, 6<t<14, 0<q≤l .

37. The method of any one of claims 1 to 37, wherein the at least one source powder is a Li-stuffed garnet compound characterized by the formula is Li7_-xLa3Zr₂0i₂ qAl₂03, wherein q is 0, 0.3, 0.35, 0.5, 0.75, or 1.0 and 0<x≤l .

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38. The method of any one of claims 1 to 38, wherein the modifying the at least one source powder comprises milling the at least one source powder and incorporating a dispersant or polymer selected from group consisting of nitriles, nitrile butadiene rubber, carboxymethyl cellulose (CMC), styrene butadiene rubber (SBR), PVDF- HFP, PAN, aqueous-compatible polymers, atactic polypropylene (aPP), silicone, polyisobutylene (PIB), ethylene propylene rubber (EPR), PMX-200 PDMS

(polydimethylsiloxane/polysiloxane, i.e., PDMS or silicone), polyacrylonitrile (PAN), polymethylmethacrylate (PMMA), poly vinylchloride (PVC), poly vinylbutyral (PVB), poly(vinylidene) fluoride-hexafluoropropylene PVDF-HFP, and combinations thereof.

39. The method of any one of claims 1 to 39, wherein providing the slurry comprises formulating the slurry by mixing at least two or more of:

a solvent selected from the group consisting of methanol, MEK, ethanol, propanol, isopropanol (IP A), acetone, cyclohexanol, toluene, acetic acid, benzene, and a combination thereof;

a binder selected from the group consisting of fish oil, PVB, KD1, an acrylic acid, triton, phosphate esters, derivatives thereof, and combinations thereof; a plasticizer selected from the group consisting of a benzyl butyl phthalate or di-butyl phthalate;

a pH modifier;

a sintering aid selected; and

a source powder selected from a lithium- stuffed garnet.

40. The method of claim 40, wherein the benzyl butyl phthalate is benzyl butyl phthalate 9S-160™

41. The method of any one of claims 1 to 41, wherein the modifying comprises

classifying the at least one source powder based on a particle size.

42. The method of claim 42, wherein classifying is a technique selected from the group consisting of sieving, centrifugation, and separating particles of different size.

43. The method of claim 42, wherein classifying is a technique selected from the group consisting of sieving, centrifugation, and separating particles of different mass.

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44. The method of any one of claims 1 to 42, wherein the slurry has a solid loading of 1% to 99 wt%, wherein the solid loading refers to the amount of source powder.

45. The method of any one of claims 1 to 42, wherein the slurry, when dried, has about 80% w/w source powder.

46. The method of any one of claims 1 to 42, wherein the slurry, when dried, has about 10-25 % w/w organic content, wherein the organic content refers to slurry components other than the source powder.

47. The method of any one of claims 1 to 42, wherein the slurry, when dried, has about 10-25 % w/w organic content, wherein the organic content refers to slurry components other than the source powder wherein the source powder is a lithium- stuffed garnet.

48. The method of any one of claims 1 to 42, wherein the amount of binder and

plasticizer in the slurry is about 10-25 % w/w organic content, wherein the organic content refers to slurry components other than the source powder wherein the source powder is a lithium- stuffed garnet.

49. The method of any one of claims 1 to 49, wherein source powder has a particle size distribution having a d₅o of 50 nm to 5 μιη.

50. The method of any one of claims 1 to 50, wherein the source powder is a lithium- stuffed garnet.

51. The method of any one of claims 1 to 50, wherein the source powder is characterized by the formula Li7_.iZr2La3Oi2+0.5Al₂O3.

52. The method of any one of claims 1 to 50, wherein the source powder is characterized by the formula Li7_.iZr2La3Oi2+0.5Al₂O3, as batched.

53. A slurry for preparing a cast green film, the slurry comprising:

at least two or more of:

a solvent selected from the group consisting of methanol, ethanol, propanol, isopropanol, butanol, isobutanol, t-butanol, pentanol, hexanol, cyclohexanone cyclohexanol, methyl acetate, ethyl acetate, methyl-

49 ethyl ketone (MEK), acetone, toluene, hexanes, acetic acid, and

combinations thereof;

a binder selected from the group consisting of fish oil, polyvinylbutylene

(PVB), KD1, an acrylic acid, triton, phosphate esters, and derivatives thereof;

a plasticizer selected from the group consisting of a benzyl butyl phthalate or di-butyl phthalate;

optionally a pH modifier;

optionally a sintering aid; and

a source powder selected from a lithium- stuffed garnet.

54. The slurry of claim 54, wherein there amount of source powder in is at least 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, or 90% by weight.

55. The slurry of claim 54, wherein there amount of source powder is at least 60%, 65%, 70%, or 75 by weight.

56. The slurry of any one of claims 54 - 56, wherein the source powder is selected from the group consisting of lithium- stuffed garnet, chemical precursors to lithium- stuffed garnet, and lithium stuffed garnet with aluminum oxide dopants.

57. The slurry of any one of claims 54 - 57, comprising a plasticizer, a pH modifier, and a sintering aid.

58. The slurry of any one of claims 54 - 58, wherein the source powder comprises garnet powder milled to d₅o of about 3 μπι, and wherein the binder comprises poly methyl methacrylate in MEK.

59. The slurry of any one of claims 54 - 59, comprising MEK, a phosphate ester, and cyclohexanone.

60. The slurry of any one of claims 54 - 60, wherein the solvent selected from methyl- ethyl ketone (MEK) or toluene.

61. The slurry of any one of claims 54 - 61 wherein the solvent comprises methyl-ethyl ketone (MEK).

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62. The slurry of any one of claims 54 - 62, wherein the solvent further comprises isopropanol (IP A).

63. The slurry of any one of claims 54 - 63, wherein the solvent further comprises

cyclohexanone.

64. The slurry of any one of claims 54 - 64 , wherein the ratio of MEKTPA is 8:2, 7:3, 6:4, 5:5, 4:6, 3 :7, or 2:8 w/w.

65. The slurry of any one of claims 54 - 65, wherein the amount of cyclohexanone is about 10-25 % by weight.

66. The slurry of any one of clams 54 - 66, wherein the solvent is an azeotrope.

67. The slurry of any one of clams 54 - 67, wherein the source powder is a lithium- stuffed garnet.

68. The slurry of claim 68, wherein the amount of lithium- stuffed garnet in the slurry is at least 70 % w/w.

69. The slurry of any one of claim 54 - 69, wherein a concentration of the source powder in the slurry is about 50 wt%, and wherein a concentration of the binder in the slurry is about 50 wt%.

70. The slurry of any one of claim 54 - 70, wherein a concentration of the source powder in the slurry is about 2-80 % w/w.

71. The slurry of any one of claim 54 - 70, wherein a concentration of the source powder in the slurry is about 50 wt%, and wherein a concentration of the binder in the slurry is about 30 wt%.

72. The slurry of claim 54 - 68, comprising about 47.5 wt% of a solvent and 0.5 wt% of a plasticizer.

73. The slurry of any one of claim 54 - 73, wherein the green film contains floes at a density of less than 100/mm² where a floe is a binder aggregate >5um in diameter as measured by FIB cross section SEM of a green film.

74. A green tape, comprising:

51 a source powder, wherein the at least one source powder is selected from the group consisting of lithium- stuffed garnet, chemical precursors to lithium- stuffed garnet, and lithium stuffed garnet with aluminum oxide dopants;

a solvent;

a binder; and

a dispersant;

wherein the green tape has a picnometry density greater than 3.9 and less than 5.0 g.cm³.

75. The green tape of claim 75, further comprising a member selected from a plasticizer, a pH modifier, and a sintering aid.

76. The green tape of claim 75, wherein the dispersant is selected from KD-1, Fish oil, and Rhodline 4160.

77. The green tape of claim 75, wherein the plasticizer is selected from DBP, BBP, and PEG.

78. The green tape of claim 75, comprising a pH modifier is selected from citric acid or ammonia hydroxide.

79. The green tape of claim 75, comprising a sintering aid is selected from MgO, A1₂0 , and combinations thereof.

80. The green tape of any one of claims 75 - 80, wherein solvent is an azeotrope.

81. The green tape of any one of claims 75 - 81, wherein solvent is a polar aproptic

azeotrope.

82. The green tape of any one of claims 75 - 82, wherein solvent is selected from methyl ethyl ketone (MEK), tetrahydrofuran, toluene, acetone, 1-butanol, 2-butanol, cyclohexane, cyclohexanol, ethanol, isopropanol, methanol, 1-propanol, propylene carbonate, hexane, 1-propanol, m-xylene, and pentane.

83. The green tape of any one of claims 75 - 83, wherein the solvent is selected from

methyl- ethyl ketone (MEK) or toluene.

84. The green tape of any one of claims 75 - 84, wherein the solvent comprises methyl- ethyl ketone (MEK).

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85. The green tape of any one of claims 75 - 85, wherein the solvent further comprises isopropanol (IP A).

86. The green tape of any one of claims 75 - 86, wherein the solvent further comprises cyclohexanone.

87. The green tape of any one of claims 75 - 87, wherein the ratio of MEKTPA is 8:2, 7:3, 6:4, 5:5, 4:6, 3:7, or 2:8 w/w.

88. The green tape of any one of claims 87- 88, wherein the amount of cyclohexanol is about 10-25 % by weight.

89. The green tape of any one of claims 75 - 89, having a polarity index greater than 3.

90. The green tape of claim any one of claims 75 - 90 comprising a source powder of a lithium- stuffed garnet having a density of 4 g/cm³; and a solvent comprising MEK and IP A.

91. The green tape of claim any one of claims 75 - 91, comprising a source powder of a lithium- stuffed garnet having a density of 4 g/cm³; and a solvent comprising MEK, IP A, and cyclohexanone.

92. A method of making a green tape, comprising

(a) providing a slurry;

(b) providing a binder mixture;

(c) mixing the slurry with the binder mixture to form a mixed slurry; and

(d) casting the mixed slurry to provide a green tape.

93. The method of claim 93, wherein the slurry comprises at least two or more of:

a solvent selected from the group consisting of methanol, ethanol, propanol, isopropanol, butanol, isobutanol, t-butanol, pentanol, hexanol, cyclohexanol, methyl acetate, ethyl acetate, methyl-ethyl ketone (MEK), acetone, toluene, hexanes, acetic acid, and combinations thereof;

a binder selected from the group consisting of fish oil, polyvinylbutylene

(PVB), KD1, an acrylic acid, triton, phosphate esters, and derivatives thereof;

53 a plasticizer selected from the group consisting of a benzyl butyl phthalate or di-butyl phthalate;

optionally a pH modifier;

optionally a sintering aid; and

a source powder selected from a lithium- stuffed garnet.

94. The method of any one of claims 92 - 93, further comprising sintering the green tape.

95. The method of any one of claims 92 - 93, comprising milling the slurry prior to step (a).

96. The method of any one of claims 96, wherein the milling the slurry comprises milling until the particle size of the particles in the slurry has a d₅o particle size of 100 nm - 200 nm, 200 nm - 300 nm, 300 nm - 400 nm, 400 nm - 500 nm, 500 nm - 600 nm, 600 nm - 700 nm, 700 nm - 800 nm, 800 nm - 900 nm, 900 nm - 1000 nm, 1000 nm - 1 lOOnm, 2000 nm - 2200nm, 3000 nm - 3300nm, or 4000 nm - 4400nm..

97. (Original) The method of any one of claims 92 - 97, wherein the slurry comprises :

The method of any one of claims 92 - 97, wherein the slurry comprises

The method of any one of claims 92 - 97, wherein the slurry comprises:

54 Rhodline 4160 6.53%

100. The method of any one of claims 92 - 97, wherein the slurry comprises

The method of any one of claims 92 - 97, wherein the binder mixture comprises

102. The method of any one of claims 92 -102, wherein the green tape has a solid loading greater than 50 % w/w.

103. The method of any one of claims 92 -103, wherein the green tape has a solid loading greater than 60 % w/w.

104. The method of any one of claims 92 -104, wherein the green tape has a solid loading greater than 70 % w/w.

105. The method of any one of claims 92 -105, wherein the green tape has a solid loading greater than 80 % w/w.

106. The method of any one of claims 92 -106, wherein the green tape has a solid loading greater than 90 % w/w.

107. The method of any one of claims 92 -107, wherein the green tape is a thin film having a film thickness less than 200 μπι and greater than 1 nm.

108. The method of any one of claims 92 -108, wherein the green tape is a thin film having a film thickness less than 100 μπι and greater than 1 nm.

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109. The method of any one of claims 92 -109, wherein the green tape is a thin film having a film thickness less than 75 μπι and greater than 1 nm.

110. The method of any one of claims 92 -110, wherein the green tape is a thin film having a film thickness less than 50 μπι and greater than 1 nm.

111. The method of any one of claims 92 -111, wherein the green tape is a thin film having a film thickness less than 25 μπι and greater than 1 nm.

112. The method of any one of claims 92 -112, wherein the green tape is a thin film having a film thickness less than 10 μπι and greater than 1 nm.

113. The method of any one of claims 92 -113, further comprising (e) drying the green tape.

114. The method of any one of claims 92 -113, further comprising (e) drying the green tape until it has an organic content amount of about 10 - 25 % w/w, wherein the organic content is the content other than the source powder.

115. The method of any one of claims 92 -113, further comprising (f) laminating a second green tape to the green tape made in claim 92 to make a stack of green tapes.

116. The method of any one of claims 92 - 115, further comprising sintering the green tape.

117. The method of any one of claims 92 - 116, further comprising sintering the stack of green tape.

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