Synthesis of olivine lithium metal phosphate cathode materials
An improved process for forming a lithium metal phosphate cathode material, a precursor to the cathode material and a battery comprising the cathode material is described. The process comprising: forming an first aqueous solution comprising a first molar concentration of Li+and a second molar concentration of PO 4 3− ; forming a second aqueous solution comprising organic acid or a salt of an organic acid and a metal selected from the group consisting of Fe, Ni, Mn and Co wherein said metal is present in a third molar concentration; allowing a precipitate to form; drying the precipitate; and calcining the precipitate thereby forming the lithium metal phosphate cathode material having a formula represented by LiMPO 4 /C wherein the lithium metal phosphate cathode material comprises up to 3 wt % carbon.
1. A process for forming a lithium metal phosphate cathode material comprising:
forming an first aqueous solution comprising a first molar concentration of Li+;
adding a second molar concentration of PO 4 3− , a third molar concentration of Fe 3+ and an organic acid or a salt of an organic acid to water to form a second aqueous solution;
combining said first aqueous solution and said second aqueous solution and allowing a precipitate to form at ambient pressure where said precipitate comprises a reaction product of said Fe 3+ and said organic acid or said salt of an organic acid;
drying said precipitate to form said a precursor comprising said reaction product and a lithium salt; and
calcining said precursor thereby forming said lithium metal phosphate cathode material having a formula represented by LiMPO 4 /C wherein said lithium metal phosphate cathode material comprises up to 3 wt % carbon.
2. The process for forming a lithium metal phosphate cathode material of claim 1 wherein said first molar concentration and said second molar concentration are in a ratio of 0.95:1 to 1.05:1.
3. The process for forming a lithium metal phosphate cathode material of claim 1 wherein said first molar concentration and said third molar concentration are in a ratio of 0.95:1 to 1.05:1.
4. The process for forming a lithium metal phosphate cathode material of claim 1 wherein said forming of said first aqueous solution comprises the addition of a lithium material comprising lithium and carbonate.
5. The process for forming a lithium metal phosphate cathode material of claim 4 wherein said lithium material is selected from the group consisting of LiHCO 3 and Li 2 CO 3 .
6. The process for forming a lithium metal phosphate cathode material of claim 5 wherein said LiHCO 3 is an in-situ reaction product of Li 2 CO 3 and CO 2 .
7. The process for forming a lithium metal phosphate cathode material of claim 1 wherein said forming of said first aqueous solution comprises the addition of a phosphate material comprising at least one counterion selected from the group consisting of NH 4 + and H + .
8. The process for forming a lithium metal phosphate cathode material of claim 7 wherein said phosphate material is selected from the group consisting of H 3 PO 4 , NH 4 H 2 PO 4 , (NH 4 ) 2 HPO 4 and (NH 4 ) 3 PO 4 .
9. The process for forming a lithium metal phosphate cathode material of claim 8 wherein said phosphate material is H 3 PO 4 or (NH 4 ) 2 HPO 4 .
10. The process for forming a lithium metal phosphate cathode material of claim 1 wherein said organic acid comprises at least one carboxylic group.
11. The process for forming a lithium metal phosphate cathode material of claim 1 wherein said organic acid is selected from the group consisting of citric acid, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioc acid, dodecanedioc acid, citric acid, isocitric acid, aconitic acid, and propane-1,2,3-tricarboxylic acid.
12. The process for forming a lithium metal phosphate cathode material of claim 11 wherein said organic acid is selected from the group consisting of oxalic acid, and citric acid.
13. The process for forming a lithium metal phosphate cathode material of claim 12 wherein said reaction product is iron oxalate.
14. The process for forming a lithium metal phosphate cathode material of claim 1 wherein said metal further comprises at least one element selected from the group consisting of Ni 2+ , Mn 2+ and Co 2+ .
15. The process for forming a lithium metal phosphate cathode material of claim 14 wherein said forming of said second aqueous solution comprises the addition of a metal salt wherein said metal salt is said salt of an organic acid.
16. The process for forming a lithium metal phosphate cathode material of claim 1 wherein said LiMPO 4 /C has the formula:
LiFe x Ni a Mn y Co z PO 4 wherein x+a++z=1
wherein:
0≤x≤1;
0≤y≤1;
0≤z≤1; and
0≤a≤0.1.
17. The process for forming a lithium metal phosphate cathode material of claim 16 wherein said 0.5≤x≤1.
18. The process for forming a lithium metal phosphate cathode material of claim 17 wherein said 0.9≤x≤1.
19. The process for forming a lithium metal phosphate cathode material of claim 16 wherein said 0≤y≤0.5.
20. The process for forming a lithium metal phosphate cathode material of claim 16 wherein said 0≤z≤0.5.
21. The process for forming a lithium metal phosphate cathode material of claim 1 wherein said carbon is a coating.
22. The process for forming a lithium metal phosphate cathode material of claim 1 comprising at least 1 wt % carbon.
23. The process for forming a lithium metal phosphate cathode material of claim 1 comprising at least 1.5 wt % to 2.5 wt % carbon.
24. The process for forming a lithium metal phosphate cathode material of claim 1 wherein said allowing said precipitate to form comprises reacting for 5-24 hours.
25. The process for forming a lithium metal phosphate cathode material of claim 1 wherein said drying is selected from thin film drying and evaporative drying.
26. The process for forming a lithium metal phosphate cathode material of claim 1 wherein said calcining is at a temperature of 620° C. to 740° C.
27. The process for forming a lithium metal phosphate cathode material of claim 1 wherein said metal further comprises at least one element selected from the group consisting of nickel, manganese and cobalt.
28. A process for forming a lithium metal phosphate cathode precursor material comprising:
forming an first aqueous solution comprising a first molar concentration of Li + ;
adding a second molar concentration of PO 4 3 , organic acid or a salt of an organic acid and a metal comprising Fe 3+ wherein said metal is present in a third molar concentration to water to form a second aqueous solution;
combining said first aqueous solution and said second aqueous solution and allowing a precipitate to form at ambient pressure where said precipitate comprises a reaction product of said Fe 3+ and said organic acid and said salt of an organic acid; and
drying said precipitate to form a precursor comprising said reaction product and a lithium salt.
29. The process for forming a lithium metal phosphate cathode precursor material of claim 28 wherein said first molar concentration and said second molar concentration are in a ratio of 0.95:1 to 1.05:1.
30. The process for forming a lithium metal phosphate cathode precursor material of claim 28 wherein said first molar concentration and said third molar concentration are in a ratio of 0.95:1 to 1.05:1.
31. The process for forming a lithium metal phosphate cathode precursor material of claim 28 wherein said forming of said first aqueous solution comprises the addition of a lithium material comprising lithium and carbonate.
32. The process for forming a lithium metal phosphate cathode precursor material of claim 31 wherein said lithium material is selected from the group consisting of LiHCO 3 and Li 2 CO 3 .
33. The process for forming a lithium metal phosphate cathode precursor material of claim 32 wherein said LiHCO 3 is an in-situ reaction product of Li 2 CO 3 and CO 2 .
34. The process for forming a lithium metal phosphate cathode precursor material of claim 28 wherein said forming of said first aqueous solution comprises the addition of a phosphate material comprising at least one counterion selected from the group consisting of NH 4 + and H + .
35. The process for forming a lithium metal phosphate cathode precursor material of claim 34 wherein said phosphate material is selected from the group consisting of H 3 PO 4 , NH 4 H 2 PO 4 , (NH 4 ) 2 HPO 4 and (NH 4 ) 3 PO 4 .
36. The process for forming a lithium metal phosphate cathode precursor material of claim 35 wherein said phosphate material is H 3 PO 4 or (NH 4 ) 2 HPO 4 .
37. The process for forming a lithium metal phosphate cathode precursor material of claim 28 wherein said organic acid comprises at least one carboxylic group.
38. The process for forming a lithium metal phosphate cathode precursor material of claim 28 wherein said organic acid is selected from the group consisting of citric acid, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioc acid, dodecanedioc acid, citric acid, isocitric acid, aconitic acid, and propane-1,2,3-tricarboxylic acid.
39. The process for forming a lithium metal phosphate cathode precursor material of claim 38 wherein said organic acid is selected from the group consisting of oxalic acid, and citric acid.
40. The process for forming a lithium metal phosphate cathode precursor material of claim 39 wherein said reaction product is iron oxalate.
41. The process for forming a lithium metal phosphate cathode precursor material of claim 28 wherein metal further comprises at least one element selected from the group consisting of Ni 2+ , Mn 2+ and Co 2+ .
42. The process for forming a lithium metal phosphate cathode precursor material of claim 41 wherein said forming of said second aqueous solution comprises the addition of a metal salt wherein said metal salt is said salt of an organic acid.
43. The process for forming a lithium metal phosphate cathode precursor material of claim 28 wherein said allowing said precipitate to form comprises reacting for 5-24 hours.
44. The process for forming a lithium metal phosphate cathode precursor material of claim 28 wherein said drying is selected from thin film drying and evaporative drying.
45. The process for forming a lithium metal phosphate cathode precursor material of claim 28 wherein said calcining is at a temperature of 620° C. to 740° C.
46. The process for forming a lithium metal phosphate cathode precursor material of claim 28 wherein metal selected from the group consisting of nickel, manganese and cobalt cobalt.
47. A process for forming battery comprising:
forming a lithium metal phosphate cathode material comprising:
forming an first aqueous solution comprising a first molar concentration of Li+;
adding a second molar concentration of PO 4 3− , organic acid or a salt of an organic acid and a metal wherein said metal comprises Fe 3+ wherein said metal is present in a third molar concentration to water to form a second aqueous solution;
combining said first aqueous solution and said second aqueous solution and allowing a precipitate to form at ambient pressure where said precipitate comprises a reaction product of said Fe 3+ and said organic acid or said salt of an organic acid;
drying said precipitate to form a precursor comprising said reaction product and a lithium salt; and
calcining said precursor thereby forming said lithium metal phosphate cathode material having a formula represented by LiMPO 4 /C wherein said lithium metal phosphate cathode material comprises up to 3 wt % carbon; and
combining said lithium metal phosphate cathode material with an anode, separator and dielectric in a battery.
48. The process for forming battery of claim 47 wherein said first molar concentration and said second molar concentration are in a ratio of 0.95:1 to 1.05:1.
49. The process for forming battery of claim 47 wherein said first molar concentration and said third molar concentration are in a ratio of 0.95:1 to 1.05:1.
50. The process for forming battery of claim 47 wherein said forming of said first aqueous solution comprises the addition of a lithium material comprising lithium and carbonate.
51. The process for forming battery of claim 50 wherein said lithium material is selected from the group consisting of LiHCO 3 and Li 2 CO 3.
52. The process for forming battery of claim 51 wherein said LiHCO 3 an in-situ reaction product of Li 2 CO 3 and CO 2 .
53. The process for forming battery of claim 47 wherein said forming of said first aqueous solution comprises the addition of a phosphate material comprising at least one counterion selected from the group consisting of NH 4+ and H+.
54. The process for forming battery of claim 53 wherein said phosphate material is selected from the group consisting of H 3 PO 4 , NH 4 H 2 PO 4 , (NH 4 ) 2 HPO 4 and (NH 4 ) 3 PO 4.
55. The process for forming battery of claim 54 wherein said phosphate material is H 3 PO 4 or (NH 4 ) 2 HPO 4 .
56. The process for forming battery of claim 47 wherein said organic acid comprises at least one carboxylic group.
57. The process for forming battery of claim 47 wherein said organic acid is selected from the group consisting of citric acid, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioc acid, dodecanedioc acid, citric acid, isocitric acid, aconitic acid, and propane-1,2,3-tricarboxylic acid.
58. The process for forming battery of claim 57 wherein said organic acid is selected from the group consisting of oxalic acid, and citric acid.
59. The process for forming battery of claim 58 wherein said reaction product is iron oxalate.
60. The process for forming battery of claim 47 wherein said metal further comprises at least one element selected from the group consisting of Ni 2+ , Mn 2+ , and Co 2+ .
61. The process for forming battery of claim 60 wherein said forming of said second aqueous solution comprises the addition of a metal salt wherein said metal salt is said salt of an organic acid.
62. The process for forming battery of claim 47 wherein said LiMPO 4 /C has the formula:
LiFe x Ni a Mn y Co z PO 4 wherein x+a+y+z=1
wherein:
0≤x≤1;
0≤y≤1;
0≤z≤1; and
0≤a≤0.1.
63. The process for forming battery of claim 62 wherein said 0.5≤x≤1.
64. The process for forming battery of claim 63 wherein said 0.9≤x≤1.
65. The process for forming battery of claim 62 wherein said 0≤y≤0.5.
66. The process for forming battery of claim 62 wherein said 0≤z≤0.5.
67. The process for forming battery of claim 47 wherein said carbon is a coating.
68. The process for forming battery of claim 47 comprising at least 1 wt % carbon.
69. The process for forming battery of claim 47 comprising at least 1.5 wt % to 2.5 wt % carbon.
70. The process for forming battery of claim 47 wherein said allowing said precipitate to form comprises reacting for 5-24 hours.
71. The process for forming battery of claim 47 wherein said drying is selected from spray drying and evaporative drying.
72. The process for forming battery of claim 47 wherein said calcining is at a temperature of 620° C. to 740° C.
73. The process for forming battery of claim 47 wherein metal is selected from the group consisting of nickel, manganese and cobalt.
74. A process for forming a lithium metal phosphate cathode material comprising:
forming an first aqueous solution comprising a first molar concentration of Li+;
forming a second aqueous solution comprising a second molar concentration of PO 4 3− , a third molar concentration of Fe 3+ and an organic acid or a salt of an organic acid;
combining said first aqueous solution and said second aqueous solution and allowing a precipitate to form at ambient pressure where said precipitate comprises a reaction product of said Fe 3+ and said organic acid or said salt of an organic acid;
drying said precipitate to form said a precursor comprising said reaction product and a lithium salt; and
calcining said precursor thereby forming said lithium metal phosphate cathode material having a formula represented by LiMPO 4 /C wherein said lithium metal phosphate cathode material comprises up to 3 wt % carbon wherein said forming of said second aqueous solution comprises the addition of Fe 2 O 3 .
75. A process for forming a lithium metal phosphate cathode precursor material comprising:
forming an first aqueous solution comprising a first molar concentration of Li+;
forming a second aqueous solution comprising a second molar concentration of PO 4 3− , organic acid or a salt of an organic acid and a metal comprising Fe 3+ wherein said metal is present in a third molar concentration;
combining said first aqueous solution and said second aqueous solution and allowing a precipitate to form at ambient pressure where said precipitate comprises a reaction product of said Fe 3+ and said organic acid or said salt of an organic acid; and
drying said precipitate to form a precursor comprising said reaction product and a lithium salt wherein said forming of said second aqueous solution comprises the addition of Fe 2 O 3 .
76. A process for forming battery comprising:
forming a lithium metal phosphate cathode material comprising:
forming an first aqueous solution comprising a first molar concentration of Li+;
forming a second aqueous solution comprising a second molar concentration of PO 4 3− , organic acid or a salt of an organic acid and a metal wherein said metal comprises Fe 3+ wherein said metal is present in a third molar concentration;
combining said first aqueous solution and said second aqueous solution and allowing a precipitate to form at ambient pressure where said precipitate comprises a reaction product of said Fe 3+ and said organic acid or said salt of an organic acid;
drying said precipitate to form a precursor comprising said reaction product and a lithium salt; and
calcining said precursor thereby forming said lithium metal phosphate cathode material having a formula represented by LiMPO 4 /C wherein said lithium metal phosphate cathode material comprises up to 3 wt % carbon; and
combining said lithium metal phosphate cathode material with an anode, separator and dielectric in a battery wherein said forming of said second aqueous solution comprises the addition of Fe 2 O 3 .