SPINEL NICKEL LITHIUM MANGANATE OXIDE MATERIAL AND PREPARATION METHOD THEREOF

1 . A spinel lithium nickel manganese oxide material, wherein,

an X-ray diffraction (XRD) pattern of the spinel lithium nickel manganese oxide material satisfies: 0<(A(43.7°)/A(18.8°)) 1/2 ≤0.2,

where A(43.7°) represents a peak area of a diffraction peak appearing in a vicinity of 43.7° in the XRD pattern, and A(18.8°) represents a peak area of a diffraction peak appearing in the vicinity of 18.8° in the XRD pattern.

2 . The spinel lithium nickel manganese oxide material according to claim 1 , wherein,

a crystal structure satisfies: 0<(A(43.7°)/A(18.8°)) 1/2 ≤0.1.

3 . The spinel lithium nickel manganese oxide material according to claim 1 , wherein,

a stoichiometric formula of the spinel lithium nickel manganese oxide material is Li x (Ni 0.5 Mn 1.5 ) n M m O 4 ,

where M is one or more elements selected from W, P, B, Nb, Mo or Ta, and as stoichiometric numbers, n+m=1, x is in a range from 0.95 to 1.1, and m is in a range from 0.001 to 0.015.

4 . The spinel lithium nickel manganese oxide material according to claim 1 , wherein,

the spinel lithium nickel manganese oxide material is a single crystal of an octahedron with corners of obtuse angles.

5 . The spinel lithium nickel manganese oxide material according to claim 1 , wherein,

a volume distribution average particle size Dv50 of the spinel lithium nickel manganese oxide material is in a range from 5 μm to 15 μm.

6 . The spinel lithium nickel manganese oxide material according to claim 5 , wherein,

the volume distribution average particle size Dv50 of the spinel lithium nickel manganese oxide material is in a range from 5 μm to 10 μm.

7 . The spinel lithium nickel manganese oxide material according to claim 1 , wherein,

a particle volume distribution span (Dv90−Dv10)/Dv50 of the spinel lithium nickel manganese oxide material is 1.0 or less.

8 . The spinel lithium nickel manganese oxide material according to claim 1 , wherein,

a BET specific surface area of the nickel manganese spinel material is in a range from 0.3 m 2 /g to 1.0 m 2 /g.

9 . The spinel lithium nickel manganese oxide material according to claim 8 , wherein,

the BET specific surface area of the nickel manganese spinel material is in a range from 0.3 m 2 /g to 0.5 m 2 /g.

10 . A preparation method of the spinel lithium nickel manganese oxide material of claim 1 , the preparation method comprising:

step S1: putting a lithium salt, a nickel manganese hydroxide precursor and an M-containing compound into a mixer for mixing to obtain a mixed material;

step S2: heating the mixed material obtained in the step S1 in an oxygen-enriched atmosphere for first sintering, naturally cooling to a room temperature after the first sintering is finished, and then carrying out ball milling to obtain a powder; and

step S3: heating the powder obtained in the step S2 in an oxygen-enriched atmosphere again for second sintering, holding a temperature after the second sintering is finished, then naturally cooling to the room temperature, and then carrying out ball milling to obtain the spinel lithium nickel manganate oxide material.

11 . The preparation method of the spinel lithium nickel manganese oxide material according to claim 10 , wherein,

in the step S1, the lithium salt and the nickel manganese hydroxide are mixed in a molar ratio of Li/(Ni+Mn) of (0.45 to 0.55):1, where (Ni+Mn) represents a total number of moles of metals nickel and manganese, and

the M-containing compound is doped in an amount according to a molar ratio of Li/M of 1:(0.001 to 0.01).

12 . The preparation method of the spinel lithium nickel manganese oxide material according to claim 11 , wherein,

the M-containing compound is doped in an amount according to a molar ratio of Li/M of 1:(0.003 to 0.007).

13 . The preparation method of the spinel lithium nickel manganese oxide material according to claim 10 , wherein,

in the step S1, the mixer is a ploughshare mixer, a high-speed mixer or an inclined mixer.

14 . The preparation method of the spinel lithium nickel manganese oxide material according to claim 10 , wherein,

in the step S2 and the step S3, a heating rate during the first sintering and the second sintering is 5° C./min or lower.

15 . The preparation method of the spinel lithium nickel manganese oxide material according to claim 14 , wherein,

in the step S2 and the step S3, the heating rate during the first sintering and the second sintering is 3° C./min or lower.

16 . The preparation method of the spinel lithium nickel manganese oxide material according to claim 10 , wherein,

in the step S2 and the step S3, an oxygen content of the oxygen-enriched atmosphere is higher than 60%.

17 . The preparation method of the spinel lithium nickel manganese oxide material according to claim 16 , wherein,

in the step S2 and the step S3, the oxygen content of the oxygen-enriched atmosphere is in a range from 80% to 100%.

18 . The preparation method of the spinel lithium nickel manganese oxide material according to claim 10 , wherein,

in the step S2 and the step S3, a pressure in a sintering furnace relative to an atmospheric pressure is in a range from 0.02 MPa to 0.08 MPa.

19 . The preparation method of the spinel lithium nickel manganese oxide material according to claim 18 , wherein,

in the step S2 and the step S3, the pressure in the sintering furnace relative to the atmospheric pressure is in a range from 0.02 MPa to 0.04 MPa.

20 . The preparation method of the spinel lithium nickel manganese oxide material according to claim 10 , wherein,

in the step S2, the first sintering is carried out at a temperature in a range from 500° C. to 1200° C., and in the step S3, the second sintering is carried out at a temperature in a range from 400° C. to 700° C.