Blended cathode materials

1. A positive electroactive material, comprising: a nanoscale lithium transition metal phosphate material comprising at least an olivinic phase that includes lithium (Li), iron (Fe), manganese (Mn), one or more dopants (D), and phosphate (PO 4 ), where an overall composition is Li a Fe 1-x-y Mn x D y (PO 4 ) z , wherein 0.350≤x<0.600, 0<y≤0.100, 1.0<a≤1.05, and 1.0<z≤1.025 and D is selected from the group consisting of Co, Ni, V, Nb, and combinations thereof; and

a lithium metal oxide,

wherein the lithium metal oxide has a specific surface area of less than about 10 m 2 /g,

wherein the nanoscale lithium transition metal phosphate material has a conductivity of at least about 10 −8 S/cm,

wherein the nanoscale lithium transition metal phosphate material is optionally doped with Ti, Zr, Nb, Al, Ta, W, Mg, or F,

wherein a weight ratio of the nanoscale lithium transition metal phosphate material to the lithium metal oxide is between 50:50 and 70:30, and

wherein the nanoscale lithium transition metal phosphate material is in the form of particulates, the particulates having a small size and a correspondingly high specific surface area; wherein

the small size is about 75 nm or less, and

the high specific surface area is greater than about 15 m 2 /g.

2. The positive electroactive material of claim 1 , wherein the nanoscale lithium transition metal phosphate material is Li a Fe 1-x-y Mn x D y (PO 4 ) z and 0.350≤x<0.500.

3. The positive electroactive material of claim 1 , wherein the nanoscale lithium transition metal phosphate material is Li a Fe 1-x-y Mn x D y (PO 4 ) z and 0.350≤x<0.450.

4. The positive electroactive material of claim 1 , wherein the nanoscale lithium transition metal phosphate material is Li a Fe 1-x-y Mn x D y (PO 4 ) z and 0.350≤x<0.500 and 0.001<y<0.100.

5. The positive electroactive material of claim 1 , wherein the nanoscale lithium transition metal phosphate material is Li a Fe 1-x-y Mn x D y (PO 4 ) z and 0.350≤x<0.500 and 0.001<y<0.050.

6. The positive electroactive material of claim 1 , wherein the nanoscale lithium transition metal phosphate material is Li a Fe 1-x-y Mn x D y (PO 4 ) z and 0.350≤x<0.500 and 0.001<y<0.050.

7. The positive electroactive material of claim 1 , wherein the nanoscale lithium transition metal phosphate material is Li a Fe 1-x-y Mn x D y (PO 4 ) z and 0.350≤x<0.500 and 0.001<y<0.050.

8. The positive electroactive material of claim 1 , wherein the nanoscale lithium transition metal phosphate material is Li a Fe 1-x-y Mn x D y (PO 4 ) z and 0.350≤x<0.500 and 0.001<y<0.050.

9. The positive electroactive material of claim 1 , wherein the nanoscale lithium transition metal phosphate material is one or more electroactive materials selected from the group consisting of:

Li 1.050 Fe 0.500 Mn 0.450 Co 0.010 Ni 0.010 V 0.030 (PO 4 ) 1.025 ,

Li 1.040 Fe 0.560 Mn 0.400 Co 0.010 Ni 0.010 V 0.020 (PO 4 ) 1.015 ,

Li 1.040 Fe 0.510 Mn 0.450 Co 0.010 Ni 0.010 V 0.020 (PO 4 ) 1.015 ,

Li 1.030 Fe 0.520 Mn 0.450 Co 0.010 Ni 0.010 V 0.010 (PO 4 ) 1.005 ,

Li 1.040 Fe 0.510 Mn 0.450 Co 0.010 Ni 0.010 V 0.030 (PO 4 ) 1.010 F 0.015 ,

Li 1.050 Fe 0.510 Mn 0.450 Co 0.0100 Ni 0.005 V 0.020 (PO 4 ) 1.020 ,

Li 1.050 Fe 0.500 Mn 0.450 Co 0.010 Nb 0.010 V 0.030 (PO 4 ) 1.025 ,

Li 1.040 Fe 0.560 Mn 0.400 Co 0.010 Nb 0.010 V 0.020 (PO 4 ) 1.015 ,

Li 1.040 Fe 0.510 Mn 0.450 Co 0.010 Nb 0.010 V 0.020 (PO 4 ) 1.015 ,

Li 1.030 Fe 0.520 Mn 0.450 Co 0.010 Nb 0.010 V 0.010 (PO 4 ) 1.005 ,

Li 1.040 Fe 0.510 Mn 0.450 Co 0.010 Nb 0.010 V 0.030 (PO 4 ) 1.010 F 0.015 , and

Li 1.050 Fe 0.510 Mn 0.450 Co 0.0100 Nb 0.005 V 0.025 (PO 4 ) 1.020 .

10. The positive electroactive material of claim 1 , wherein the lithium metal oxide is selected from the group consisting of lithium nickel cobalt aluminum oxide (NCA), lithium nickel cobalt magnesium oxide (NCMg), lithium nickel cobalt manganese oxide (NCM), lithium nickel cobalt rare earth oxide (NCRE), spinel lithium manganese oxide (LMO), layered layered oxide cathode (LLC), lithium cobalt oxide (LCO), layered Mn oxide, and combinations thereof.

11. The positive electroactive material of claim 1 , wherein the lithium metal oxide is a lithium nickel cobalt manganese oxide (NCM).

12. The positive electroactive material of claim 1 , wherein the lithium metal oxide is a lithium nickel cobalt aluminum oxide (NCA).

13. The positive electroactive material of claim 1 , wherein the lithium metal oxide is lithium nickel cobalt manganese oxide (NCM) and the nanoscale lithium transition metal phosphate material is Li a Fe 1-x-y Mn x D y (PO 4 ) z , wherein 0.350≤x<0.500.

14. The positive electroactive material of claim 1 , further comprising additional lithium transition metal polyanion materials.

15. The positive electroactive material of claim 1 , wherein the positive electroactive material comprises from about 40-70% of the nanoscale lithium transition metal phosphate material.

16. The positive electroactive material of claim 1 ,

wherein the nanoscale lithium transition metal phosphate material is in the form of a particulate;

wherein the lithium metal oxide is in the form of a particulate; and

wherein a ratio of the specific surface area of the nanoscale lithium transition metal phosphate material to the specific surface area of the lithium metal oxide is between about 1.5 and 100.

17. A positive electroactive material, comprising: a doped nanoscale lithium transition metal phosphate material having at least an olivinic phase that comprises lithium (Li), iron (Fe), manganese (Mn), one or more dopants (D), and phosphate (PO 4 ), where an overall stoichiometric composition includes v amount of Li, w amount of Fe, x amount of Mn, y amount of D, and z amount of PO 4 , where w+x+y=1.0, a ratio of v:(w+x+y) ranging from about 1.0 to about 1.05, a ratio of z:(w+x+y) ranging from about 1.0 to about 1.025, and D is one or more metals selected from the group consisting of cobalt (Co), nickel (Ni), vanadium (V), niobium (Nb), and mixtures thereof, and x ranges from about 0.350 to less than 0.600; and

a lithium metal oxide,

wherein the lithium metal oxide has a specific surface area of less than about 10 m 2 /g,

wherein the nanoscale lithium transition metal phosphate material is optionally doped with Ti, Zr, Nb, Al, Ta, W, Mg, or F,

wherein a weight ratio of the nanoscale lithium transition metal phosphate material to the lithium metal oxide is between 50:50 and 70:30, and

wherein the nanoscale lithium transition metal phosphate material is in the form of particulates having a size of about 75 nm or less, and

wherein the nanoscale lithium transition metal phosphate material particulates have a specific surface area greater than about 15 m 2 /g to form a high surface to volume ratio relative to the size of the particulates.

18. The positive electroactive material of claim 17 , wherein x ranges from 0.400 to 0.550 and y ranges from 0.005 to 0.05.

19. The positive electroactive material of claim 17 , wherein the nanoscale lithium transition metal phosphate material is one or more electroactive materials selected from the group consisting of:

Li 1.025 Fe 0.580 Mn 0.400 Co 0.020 PO 4 , and

Li 1.025 Fe 0.530 Mn 0.450 Co 0.020 PO 4 .

20. The positive electroactive material of claim 17 , wherein the lithium metal oxide is selected from the group consisting of lithium nickel cobalt aluminum oxide (NCA), lithium nickel cobalt magnesium oxide (NCMg), lithium nickel cobalt manganese oxide (NCM), lithium nickel cobalt rare earth oxide (NCRE), spinel lithium manganese oxide (LMO), layered layered oxide cathode (LLC), lithium cobalt oxide (LCO), layered Mn oxide, and combinations thereof.

21. The positive electroactive material of claim 17 , further comprising additional lithium transition metal polyanion materials.

22. The positive electroactive material of claim 17 , wherein the positive electroactive material comprises from about 40-70% of the nanoscale lithium transition metal phosphate material.