US 12,107,266 B2
Composite positive electrode material and preparation method thereof, secondary battery, battery group including secondary battery, and electric apparatus including secondary battery
Bangrun Wang, Ningde (CN); and Na Liu, Ningde (CN)
Assigned to CONTEMPORARY AMPEREX TECHNOLOGY CO., LIMITED, Ningde (CN)
Filed by CONTEMPORARY AMPEREX TECHNOLOGY CO., LIMITED, Ningde (CN)
Filed on Jul. 26, 2022, as Appl. No. 17/873,861.
Application 17/873,861 is a continuation of application No. PCT/CN2021/099876, filed on Jun. 11, 2021.
Prior Publication US 2022/0399540 A1, Dec. 15, 2022
Int. Cl. H01M 4/36 (2006.01); H01M 4/505 (2010.01); H01M 4/525 (2010.01); H01M 4/58 (2010.01); H01M 10/0525 (2010.01); H01M 4/02 (2006.01)
CPC H01M 4/366 (2013.01) [H01M 4/505 (2013.01); H01M 4/525 (2013.01); H01M 4/5825 (2013.01); H01M 10/0525 (2013.01); H01M 2004/021 (2013.01); H01M 2004/028 (2013.01)] 14 Claims
OG exemplary drawing
 
1. A preparation method of a composite positive electrode material, comprising the following steps:
providing a kernel material, wherein the kernel material contains a lithium-rich metal oxide, and a surface of the lithium-rich metal oxide comprises a free lithium compound;
providing a positive electrode active material precursor;
attaching the positive electrode active material precursor to at least a partial surface of the kernel material; and
making the positive electrode active material precursor react with the free lithium compound comprising: performing heat treatment at 600° C.-800° C. in a protective gas atmosphere for 2 hours to 8 hours; so that a positive electrode active material is formed on at least a partial surface of the lithium-rich metal oxide, to obtain the composite positive electrode material;
wherein the free lithium compound comprises one or more of Li2O, LiOH, and Li2CO3, and a mass percentage of the free lithium compound in the kernel material that is obtained through titration is 0.5 wt %-15 wt %;
wherein the lithium-rich metal oxide is selected from one or more of Li2M1O2, Li2M2O3, Li3M3O4, Li5M4O4, and Li6M5O4, wherein
M1 comprises one or more of Ni, Co, Fe, Mn, Zn, Mg, Ca, and Cu;
M2 comprises one or more of Mn, Sn, Mo, Ru, and Ir;
M3 comprises one or more of V, Nb, Cr, and Mo;
M4 comprises one or more of Fe, Cr, V, and Mo;
M5 comprises one or more of Co, V, Cr, and Mo; and
a valence state of each metal element other than Li in the lithium-rich metal oxide is lower than a highest oxidation valence state of the metal element; and wherein the positive electrode active material precursor is selected from one or more of Nix1COy1Mnz1(OH)2, Nix2Coy2Alz2(OH)2, Nix3Coy3Mnz3CO3, Nix4Coy4ALz4CO3, and MPO4, wherein x1+y1+z1=1, x2+y2+z2=1, x3+y3+z3=1, x4+y4+z4=1, and M is selected from one or more of Fe, Ni, Co, and Mn.