POSITIVE ELECTRODE ACTIVE MATERIAL AND THE METHOD FOR PREPARING THE SAME, SECONDARY BATTERY, BATTERY MODULE, BATTERY PACK, AND ELECTRICAL DEVICE

1 . A positive electrode active material, comprising a layered sodium composite oxide containing antimony having a chemical formula of Formula I,

Na x Mn a Fe b Ni c Sb d LeO 2   (I),

in which 0.7<x≤1, 0<a, 0≤b, 0.1<c≤0.3, 0<d≤0.1, 0≤e, a+b+c+d+e=1, (b+c)/(a+d+e)≤1, and L is one or more selected from Cu, Li, Ti, Zr, K, Nb, Mg, Ca, Mo, Zn, Cr, W, Bi, Sn, Ge, Al, Si, La, Ta, P, and B.

2 . The positive electrode active material according to claim 1 , wherein,

in Formula I, 0.3≤a≤0.4, 0.2≤b≤0.3, 0.15≤c≤0.2, 0.05≤d≤0.1, 0.05≤e≤0.1, a+b+c+d+e=1, and 0.4<(b+c)/(a+d+e)≤1.

3 . The positive electrode active material according to claim 1 , wherein

L is one or more selected from Cu, Li, Ti, Zr, Mg, Ca, Zn, Bi, Sn, Al, Si, La, Ta, P, and B, and optionally, L is one or more selected from Cu, Li, Mg, Zn, Al, Si, and B.

4 . The positive electrode active material according to claim 1 , wherein

the sodium composite oxide containing antimony includes an O3 phase which has a layered crystal structure with a space group R 3 m.

5 . The positive electrode active material according to claim 1 , wherein

the sodium composite oxide containing antimony has an interlayer spacing of from 0.53 nm to 0.54 nm.

6 . The positive electrode active material according to claim 1 , wherein

the sodium composite oxide containing antimony has a X-ray diffraction spectrum that satisfies I 1 /I 0 ≥0.2,

wherein I 1 is the peak intensity of the X-ray diffraction peak on the 003 crystal surface of the O3 phase of the sodium composite oxide containing antimony after being immersed in deionized water for 24 hours, and I 0 is the peak intensity of the X-ray diffraction peak on the 003 crystal surface of the O3 phase of the sodium composite oxide containing antimony before being immersed in deionized water.

7 . The positive electrode active material according to claim 1 , wherein,

the positive electrode active material satisfies one or more of the following conditions (1) to (4):

(1) the volume average particle size Dv50 of the positive electrode active material is from 3 μm to 30 μm, and optionally from 5 μm to 15 μm;

(2) the specific surface area of the positive electrode active material is from 0.1 m 2 /g to 5 m 2 /g, and optionally from 0.3 m 2 /g to 3 m 2 /g;

(3) the tap density of the positive electrode active material is from 1 g/cm 3 to 3 g/cm 3 , and optionally from 1.5 g/cm 3 to 2.5 g/cm 3 ; and

(4) the powder compaction density of the positive electrode active material under a pressure of 8 tons is from 3 g/cm 3 to 5 g/cm 3 , and optionally from 3.5 g/cm 3 to 4.5 g/cm 3 .

8 . A method for preparing a positive electrode active material, comprising

providing a raw material that has elements and the portions thereof satisfying the chemical formula of Formula I according to claim 1 ;

calcining the raw material, to obtain a positive electrode active material,

wherein, the positive electrode active material comprises a layered sodium composite oxide containing antimony, wherein the sodium composite oxide containing antimony has a chemical formula of Formula I,

Na x Mn a Fe b Ni c Sb d LeO 2   (I),

in which 0.7<x≤1, 0<a, 0≤b, 0.1<c≤0.3, 0<d<0.1, 0≤e, a+b+c+d+e=1, (b+c)/(a+d+e)≤1, and L is one or more selected from Cu, Li, Ti, Zr, K, Nb, Mg, Ca, Mo, Zn, Cr, W, Bi, Sn, Ge, Al, Si, La, Ta, P, and B.

9 . The method for preparing a positive electrode active material according to claim 8 , wherein,

the providing a raw material comprises

stirring a sodium source, manganese source, iron source, nickel source, antimony source, and L source homogeneously, to obtain the raw material,

wherein the L source is selected one or more sources selected from Cu source, Li source, Ti source, Zr source, K source, Nb source, Mg source, Ca source, Mo source, Zn source, Cr source, W source, Bi source, Sn source, Ge source, Al source, Si source, La source, Ta source, P source, and B source.

10 . The method for preparing a positive electrode active material according to claim 8 , wherein, the raw material satisfies one or more of the following conditions (5) to (9):

(5) the sodium source is one or more selected from Na 2 CO 3 , NaHCO 3 , NaOH, and Na 2 O 2 ;

(6) the iron source is one or more selected from Fe 2 O 3 , Fe 3 O 4 , and FeO;

(7) the manganese source is one or more selected from Mn 2 O 3 , Mn 3 O 4 , MnO, and MnO 2 ;

(8) the nickel source is selected from NiO or Ni(OH) 2 ;

(9) the antimony source is one or more selected from elemental antimony, antimony-containing oxides, or antimony salts.

11 . The method for preparing a positive electrode active material according to claim 8 , wherein providing a raw material comprises

mixing iron source, manganese source, nickel source, and L source with water, to obtain a mixture solution, wherein the L source is one or more selected from Cu source, Li source, Ti source, Zr source, K source, Nb source, Mg source, Ca source, Mo source, Zn source, Cr source, W source, Bi source, Sn source, Ge source, Al source, Si source, La source, Ta source, P source, and B source;

mixing the mixture solution with a precipitant, to form a precipitate;

stirring the precipitate, sodium source, and antimony source homogeneously, to obtain the raw material.

12 . The method for preparing a positive electrode active material according to claim 11 , wherein the raw material satisfies one or more of the following conditions (10) to (15):

(10) the sodium source is one or more selected from Na 2 CO 3 , NaHCO 3 , NaOH, and Na 2 O 2 ;

(11) the iron source is one or more selected from iron-containing chlorides, iron-containing sulfates, and iron-containing nitrates;

(12) the manganese source is one or more selected from manganese-containing chlorides, manganese-containing sulfates, and manganese-containing nitrates;

(13) the nickel source is one or more selected from nickel-containing chlorides, nickel-containing sulfates, and nickel-containing nitrates;

(14) the antimony source is one or more selected from elemental antimony, antimony-containing oxides, or antimony salts;

(15) the precipitant is one or more selected from hydroxides, carbonates, and oxalates.

13 . A secondary battery, characterized in comprising the positive electrode active material according to claim 1 .

14 . A secondary battery, characterized in comprising the positive electrode active material prepared by the method for preparing the positive electrode active material according to claim 8 .

15 . A battery module, including the secondary battery according to claim 13 .

16 . A battery pack, including the battery module according to claim 15 .

17 . An electrical device, including the secondary battery according to claim 13 .

18 . A powder device, including the battery model according to claim 15 .

19 . A powder device, including the battery pack according to claim 16 .