Lithium-rich nickel-manganese-cobalt cathode powders for lithium-ion batteries
The invention provides a dual component lithium-rich layered oxide positive electrode material for a secondary battery, the material consisting of a single-phase lithium metal oxide with space group R-3m and having the general formula Li 1 + b N 1−b O 2 , wherein 0.155≤b≤0.25 and N=Ni x Mn y CO z Zr c A d , with 0.10≤x≤0.40, 0.30≤y≤0.80, 0<z≤0.20, 0.005≤c≤0.03, and 0≤d≤0.10, and wherein x+y+z+c+d=1, with A being a dopant comprising at least one element, and the material further consisting of a Li 2 ZrO 3 component.
1. A dual component lithium-rich layered oxide positive electrode material for a secondary battery, the material comprising a single-phase lithium metal oxide component and a Li 2 ZrO 3 component, wherein the single-phase lithium metal oxide component has a general formula Li 1+b N 1−b O 2 , wherein 0.155≤b≤0.25 and N=Ni x Mn y Co z Zr c A d , wherein 0.10≤x≤0.40, 0.30≤y≤0.80, 0<z≤0.20, 0.005≤c≤0.03, 0≤d≤0.10, wherein x+y+z+c+d=1, with A being a dopant comprising at least one element, and wherein the Li 2 ZrO 3 component is distributed in the layered oxide material.
2. The dual component lithium-rich layered oxide positive electrode material of claim 1 , wherein 0.205<b≤0.25.
3. The dual component lithium-rich layered oxide positive electrode material of claim 2 , wherein the Li 2 ZrO 3 component is homogeneously distributed in the layered oxide material.
4. The dual component lithium-rich layered oxide positive electrode material of claim 1 , wherein 0.15≤x≤0.30, 0.50≤y≤0.75, 0.05<z≤0.15, 0.01≤c≤0.03, and 0≤d≤0.10.
5. The dual component lithium metal oxide powder of claim 1 , wherein the dopant A comprises one or more elements selected from the group consisting of Al, Mg, Ti, Cr, V, W, Nb and Ru.
6. The dual component lithium metal oxide powder of claim 1 , wherein 0.15≤x≤0.25, 0.55≤y≤0.70, and 0.05≤z≤0.15.
7. The dual component lithium metal oxide powder of claim 1 , wherein x=0.22±0.02, y=0.67±0.05, z=0.11±0.05 and 0.18≤b≤0.21.
8. A method for preparing the dual component lithium-rich layered oxide positive electrode material according to claim 1 , comprising:
providing a precursor comprising Ni, Mn and Co,
providing a precursor comprising Zr that is insoluble in water,
providing a precursor comprising dopant A,
providing a precursor comprising Li,
preparing a dry mixture comprising the precursors of Ni, Mn and Co; lithium, Zr and A, wherein the amounts of the different elements are stoichiometrically controlled to reach a general formula Li 1+b N 1−b O 2 , with 0.155≤b≤0.25 and N=Ni x Mn y Co z Zr c A d , with 0.10≤x≤0.40, 0.30≤y≤0.80, 0<z≤0.20, 0.005≤c≤0.03, and 0≤d≤0.10, and wherein x+y+z+c+d=1,
heating the mixture to a sintering temperature of at least 700° C.,
sintering the mixture at the sintering temperature for a period of time, and
cooling the sintered mixture.
9. The method according to claim 8 , wherein 0.205<b≤0.25.
10. The method according to claim 8 , wherein the step of providing a precursor comprising Ni, Mn and Co comprises:
providing separate sources of Ni, Mn and Co, the sources being one of nitrates, sulfates or oxalates,
mixing stoichiometrically controlled quantities of the separate sources in a water-based liquid to reach a general formula Ni x Mn y Co z ,
adding a precipitation agent that is either a hydroxide or a carbonate, whereby the precursor, being a Ni—Mn—Co oxy-hydroxide or a Ni—Mn—Co carbonate is precipitated.
11. The method according to claim 8 , wherein the Zr precursor is ZrO 2 .
12. The method according to claim 8 , wherein the Zr precursor is a sub-micron sized ZrO 2 powder having a D50<500 nm and a BET≥40 m 2 /g.
13. The method according to claim 8 , wherein the precursor of the dopant A is one or more compounds selected from the group consisting of Al 2 O 3 , TiO 2 , MgO, WO 3 , Cr 2 O 3 , V 2 O 5 , Nb 2 O 5 and RuO 2 .