US 11,658,298 B2
Stabilized lithium metal oxide electrode material and method of preparation
Albert L. Lipson, Forest Park, IL (US); and Jessica L. Durham, Frankfort, IL (US)
Assigned to UCHICAGO ARGONNE, LLC, Chicago, IL (US)
Filed by UCHICAGO ARGONNE, LLC, Chicago, IL (US)
Filed on May 19, 2020, as Appl. No. 16/877,925.
Prior Publication US 2021/0367235 A1, Nov. 25, 2021
Int. Cl. H01M 4/525 (2010.01); H01M 4/36 (2006.01); H01M 4/04 (2006.01); H01M 10/0525 (2010.01); H01M 10/0568 (2010.01); H01M 10/0569 (2010.01); H01M 50/40 (2021.01)
CPC H01M 4/525 (2013.01) [H01M 4/0471 (2013.01); H01M 4/366 (2013.01); H01M 10/0525 (2013.01); H01M 10/0568 (2013.01); H01M 10/0569 (2013.01); H01M 50/40 (2021.01); H01M 2300/002 (2013.01)] 13 Claims
OG exemplary drawing
 
1. A stabilized layered lithium metal oxide (LMO) material comprising microparticles of a lithium metal oxide of empirical formula LiMO2, wherein M comprises a Ni, Mn, Co, or a combination of two or more thereof, and optionally up to 5 mole percent of one or more additional metal element, M′; the individual microparticles comprise a core of a first layered LMO in which M comprises Ni, Mn, Co, or a combination of two or more thereof, and optionally M′; a 50 to 2000 nm thick coating of a second layered LMO in which M comprises Co, Mn, or a combination thereof, and optionally M′, surrounding the core; and an interface region of a third layered LMO in which M comprises Ni, Co, Mn, or a combination of two or more thereof, and optionally M′, between the core and the coating; wherein the interface region has a thickness of about 50 to about 2000 nm; the concentrations of M′, Ni, Mn, and Co in the interface region vary in the direction from surface to core; the Ni and Co concentrations are substantially uniform within the core when the core comprises Ni and Co; and the Mn concentration of the core varies by up to about +/−5 percent in nested concentric regions within the core when the core comprises Mn and Co.
 
5. A stabilized layered lithium metal oxide (LMO) material comprising microparticles of a lithium nickel manganese cobalt oxide (NMC) of formula LiMO2, wherein M comprises a combination of Ni, Mn, and Co; the microparticles comprise a core of a first layered LMO in which M comprises Ni, Mn, and Co; a 50 to 2000 nm thick coating of a second layered LMO in which M comprises Mn, Co, or a combination thereof surrounding the core; and an interface region of a third layered LMO in which M comprises Ni, Mn, and Co between the core and the coating; the interface region has a thickness of about 50 to about 2000 nm; the Ni concentration of the interface region increases in the direction from surface to core, while the Mn and Co concentrations of the interface region decrease in the direction from surface to core when the second LMO comprises Mn; the Ni and Co concentrations are substantially uniform within the core, and the Mn concentration of the core varies by up to about +/−5 percent in nested concentric regions within the core.
 
10. A stabilized layered lithium metal oxide (LMO) material comprising microparticles of a lithium metal oxide of empirical formula LiMO2 wherein M comprises Ni, Mn, Co, or a combination of two or more thereof; wherein the microparticles comprise a core of a first layered LMO, a coating of a second layered LMO, and an interface layer of a third layered LMO between the core and the coating; and the stabilized layered lithium metal oxide material is prepared by a method comprising the sequential steps of:
(a) continuously adding an alkali metal hydroxide solution, an aqueous ammonium hydroxide solution, and an aqueous solution of metal salts to a stirring reactor at a temperature of about 25 to 60° C., at hydroxide addition rates sufficient to maintain a constant pH of greater than or equal to 11 in the reactor, thereby coprecipitating metal hydroxide core precursor particles; and halting the additions of the solutions when the average particle size of the core precursor particles reaches a selected target size; the metal salts comprising a nickel salt, a manganese salt, a cobalt salt, or a combination of two or more thereof;
(b) continuously adding an aqueous coating solution comprising a manganese salt, a cobalt salt, or a combination thereof, to a stirring slurry of the core precursor particles formed in step (a) without addition of any hydroxide and without controlling the pH, at a temperature of about 25 to 60° C.; thereby coprecipitating cobalt and manganese hydroxide on the surface and interior of the core precursor particles to form coated precursor particles; and halting addition of the coating solution when the pH drops by a selected target level of about 0.1 to 1 pH units;
(c) recovering the coated precursor particles;
(d) mixing the recovered coated precursor particles with at least one molar equivalent of lithium hydroxide relative to the total moles of metal hydroxides present in the coated precursor particles to produce a precursor mixture; and
(e) calcining the precursor mixture from step (d) at a temperature in the range of about 725 to 900° C. for about 4 to 50 hours, to form the stabilized lithium metal oxide material.