Bimodal lithium transition metal based oxide powder for use in a rechargeable battery

1. A bimodal lithium transition metal oxide based powder for a rechargeable battery, comprising:

a first lithium transition metal oxide based powder having an average particle size (D50) of at least 15 μm and comprising a material A, having a layered crystal structure comprising the elements Li, a metal M and oxygen, wherein the Li content is stoichiometrically controlled, wherein the metal M has a formula M=Co 1−a M′ a , with 0≤a≤0.05, wherein M′ is one or more metals selected from the group consisting of Al, Ga and B, and wherein the first lithium transition metal oxide based powder has an electrical conductivity of less than 10 −4 S/cm; and

a second lithium transition metal oxide based powder having the formula Li 1+b N′ 1−b O 2 , wherein 0.10≤b≤0.25, and N′=Ni x Mn y Co z A d , wherein 0.15≤x≤0.30, 0.50≤y≤0.75, 0.05<z≤0.15 and 0≤d≤0.10, and wherein A is a dopant; wherein the second powder has an average particle size (D50) of less than 5 μm and wherein the ratio of the D50 value of the first powder to the D50 value of the second powder is at least 5:1.

2. A bimodal lithium transition metal oxide based powder for a rechargeable battery, comprising:

a first lithium transition metal oxide based powder having an average particle size (D50) of at least 15 μm and comprising a material B, having a core and a surface layer, wherein the core comprises a layered crystal structure comprising the elements Li, a metal M and oxygen, wherein the Li content is stoichiometrically controlled, wherein the metal M has a formula M=Co 1−a M′ a , with 0≤a≤0.05, and wherein M′ is one or more metals selected from the group consisting of Al, Ga and B; wherein the surface layer comprises a mixture of the elements of the core and inorganic N-based oxides, wherein N comprises one or more metals selected from the group consisting of Mg, Ti, Fe, Cu, Ca, Ba, Y, Sn, Sb, Na, Zn, Zr, Si, Nb, Mo, Ru, Rh, Pd, Ag, Cd, Sc, Ce, Pr, Nd, Gd, Dy, and Er, and wherein the first lithium transition metal oxide based powder has an electrical conductivity of less than 10 −4 S/cm; and

a second lithium transition metal oxide based powder having the formula Li 1+b N′ 1−b O 2 , wherein 0.10≤b≤0.25, and N′=Ni x Mn y Co z A d , wherein 0.15≤x≤0.30, 0.50≤y≤0.75, 0.05≤z≤0.15 and 0≤d≤0.10, and wherein A is a dopant; wherein the second powder has an average particle size (D50) of less than 5 μm.

3. The bimodal lithium transition metal oxide based powder of claim 1 , wherein the first lithium transition metal oxide based powder has a surface area measured by BET of less than 0.20 m 2 /g, and the second lithium transition metal oxide based powder has a surface area measured by BET of at least 0.50 m 2 /g.

4. The bimodal lithium transition metal oxide based powder of claim 2 , wherein the ratio of the weight fraction of the first lithium transition metal oxide based powder to the weight fraction of the second lithium transition metal oxide based powder is at least 2:1.

5. The bimodal lithium transition metal oxide based powder of claim 2 , wherein the first lithium transition metal oxide based powder has an electrical conductivity of less than 10'S/cm, measured under a pressure of 63.7 MPa.

6. A positive electrode for a rechargeable battery, comprising the bimodal lithium transition metal oxide based powder of claim 1 , and having a porosity ≤15%.

7. A rechargeable battery comprising the positive electrode of claim 6 , wherein less than 15 vol % of organic electrolyte fills pores of the positive electrode.

8. The rechargeable battery of claim 7 , wherein the total mass of electrolyte per mass of positive electrode is less than 15%.

9. The bimodal lithium transition metal oxide based powder of claim 2 , wherein the first lithium transition metal oxide based powder comprises large dense particles having a D50 of at least 15 μm, and wherein the ratio of the D50 value of the first lithium transition metal oxide based powder to the D50 value of the second lithium transition metal oxide based powder is at least 3:1.

10. The bimodal lithium transition metal oxide based powder of claim 2 , wherein the first lithium transition metal oxide based powder has a surface area measured by BET of less than 0.20 m 2 /g, and the second lithium transition metal oxide based powder has a surface area measured by BET of at least 0.50 m 2 /g.

11. A positive electrode for a rechargeable battery, comprising the bimodal lithium transition metal oxide based powder of claim 2 , and having a porosity ≤15%.

12. A rechargeable battery comprising the positive electrode of claim 11 , wherein less than 15 vol % of organic electrolyte fills pores of the positive electrode.