Methods for preparing positive electrode material for rechargeable lithium ion batteries

Patent metadata

Field	Value
Publication number	US-2021143423-A1
Application number	US-201917041022-A
Country	US
Kind code	A1
Filing date	Mar 13, 2019
Priority date	Mar 29, 2018
Publication date	May 13, 2021
Grant date	—

Abstract

A method for preparing a powderous positive electrode material comprising single crystal monolithic particles and having a general formula Li 1+a ((Ni z (Ni 1/2 Mn 1/2 ) y Co x ) 1-k A k ) 1-a O 2 , wherein A is a dopant, −0.03≤a≤0.06, 0.05≤x≤0.35, 0.10≤z≤0.95, x+y+z=1 and k≤0.05 is described. The method comprises providing a mixture comprising a Ni- and Co-bearing precursor and a Li bearing precursor, subjecting the mixture to a multiple step sintering process whereby in the final sintering step a sintered lithiated intermediate material is obtained comprising agglomerated primary particles having a primary particle size distribution with a D50 between 2.0 and 8.0 μm, subjecting the lithiated intermediate material to a wet ball milling step to deagglomerate the agglomerated primary particles and obtain a slurry comprising deagglomerated primary particles, separating the deagglomerated primary particles from the slurry, and heat treating the deagglomerated primary particles at a temperature between 300° C. and at least 20° C. below the temperature in the final sintering step.

First claim

1 - 15 . (canceled)

16 . A method for preparing a powderous positive electrode material comprising single crystal monolithic particles comprising Ni and Co and having a general formula Li 1+a ((Ni z (Ni 1/2 Mn 1/2 ) y Co x ) 1-k A k ) 1-a O 2 , wherein A is a dopant, −0.03≤a≤0.06, 0.05≤x≤0.35, 0.10≤z≤0.95, x+y+z=1 and k≤0.05, the method comprising the steps of
providing a mixture comprising a Ni- and Co-bearing precursor and a Li bearing precursor,
subjecting the mixture to a multiple step sintering process whereby in the final sintering step a sintered lithiated intermediate material is obtained comprising agglomerated primary particles having a primary particle size distribution with a D50 between 2.0 and 8.0 μm,
subjecting the lithiated intermediate material to a wet ball milling step whereby the agglomerated primary particles are deagglomerated and a slurry comprising deagglomerated primary particles is obtained,
separating the deagglomerated primary particles from the slurry, and
heat treating the deagglomerated primary particles at a temperature between 300° C. and at least 20° C. below the temperature in the final sintering step of the multiple step sintering process, whereby single crystal monolithic particles comprising Ni and Co are obtained.

17 . The method according to claim 16 , wherein the Ni- and Co-bearing precursor has a particle size distribution with a D50≥10 μm.

18 . The method according to claim 16 , wherein the Ni- and Co-bearing precursor is obtained from a pyrolysis process of a Ni- and Co-bearing sulfate or chloride solution.

19 . The method according to claim 16 , wherein in the mixture comprising a Ni- and Co-bearing precursor and a Li bearing precursor, the Li to transition metal ratio is between 0.65 and 0.95, and the multiple step sintering process comprises the following steps:
a first sintering step in an oxidizing atmosphere at a temperature between 650 and 850° C., for a time between ⅓ and 15 hours, thereby obtaining a lithium deficient precursor powder, mixing the lithium deficient precursor powder with one of LiOH, Li 2 O or LiOH.H 2 O, thereby obtaining a second mixture whereby the mixture has a Li to transition metal ratio between 0.95 and 1.10, and sintering the second mixture in an oxidizing atmosphere at a temperature between 800 and 1000° C., for a time between 6 and 36 hours.

20 . The method according to claim 16 , further comprising a dry milling-step performed in an air classifying mill or an air jet mill between the step of subjecting the mixture to a multiple step sintering process and the wet ball milling step.

21 . The method according to claim 16 , wherein the wet ball milling step is performed in a solution with the solvent in the solution being water.

22 . The method according to claim 16 , wherein the wet ball milling step is performed in a solution comprising a solvent and between 30 and 70 wt % of lithiated intermediate material, and using one of steel, ZrO 2 , Al 2 O 3 or WC beads having a diameter between 0.5 and 10 mm.

23 . The method according to claim 21 , wherein the wet ball milling step is a cascade wet-milling step performed using one of steel, ZrO 2 , Al 2 O 3 or WC beads, the cascade wet ball milling step comprising a first step using beads of 10 to 50 mm and a milling speed <20 cm/s, and a final step using beads of 0.2 to 5 mm and a milling speed <500 cm/s.

24 . The method according to claim 16 , wherein the wet ball milling step is performed until achieving a slurry comprising deagglomerated primary particles with a D50 between 2 and 8 μm and a span below 1.3.

25 . The method according to claim 16 , wherein the heat treatment step of the deagglomerated primary particles is performed at temperature between 300 and 850° C.

26 . The method according to claim 16 , wherein in the wet ball milling step, a dopant A-bearing precursor or a Co-bearing precursor is added to the solution.

27 . The method according to claim 26 , wherein the dopant A- or Co-bearing precursor is one of aluminum or cobalt hydroxide, CoSO 4 , Al 2 (SO 4 ) 3 or NaAl(OH) 4 .

28 . The method according to claim 26 , wherein the Co-bearing precursor is a Co-nano oxide or a cobalt salt, and the dopant A-bearing precursor is a nano oxide or salt of one or more of Al, Mg, Zr, Nb, Si, P, Mo, Ba, Sr, Ca, Zn, Cr, V, and Ti.

29 . The method according to claim 16 , wherein the deagglomerated primary particles separated from the slurry are dry coated with nano particles comprising one of Al(OH) 3 , Al 2 O 3 , Co nitrate or a Mn doped Co oxide, before the heat treatment step.

30 . A powderous positive electrode material comprising single crystal monolithic particles comprising Ni and Co and having a general formula Li 1+a ((Ni z (Ni 1/2 Mn 1/2 ) y Co x ) 1-k A k ) 1-a O 2 , wherein A is a dopant, −0.03≤a≤0.06, 0.05≤x≤0.35, 0.10≤z≤0.95, x+y+z=1 and k≤0.05, the particles having a particle size distribution with a D50 between 2.0 and 8.0 μm, and with a span ≤1.5.

Assignees

• Umicore Nv
• Umicore Korea Ltd

Inventors

• Paulsen Jens
• Kumakura Shinichi
• Yang Taehyeon
• Kim Dae-Hyun
• Yang Hyejeong

Classifications

• C01P2004/03

  obtained by SEM · CPC title

• C01G53/50 Primary

  of the type (MnO2)n-, e.g. Li(NixMn1-x)O2 or Li(MyNixMn1-x-y)O2 · CPC title

• H01M2004/028

  Positive electrodes · CPC title

• C01P2006/40

  Electric properties · CPC title

• C01P2004/51

  Particles with a specific particle size distribution · CPC title