Positive electrode active material, positive electrode plate, secondary battery, battery module, battery pack and power consuming device

Patent metadata

Field	Value
Publication number	US-2024282969-A1
Application number	US-202418641410-A
Country	US
Kind code	A1
Filing date	Apr 21, 2024
Priority date	Oct 22, 2021
Publication date	Aug 22, 2024
Grant date	—

Abstract

A positive electrode active material has an inner core and a shell coating the inner core, wherein the inner core comprises at least one of a ternary material, dLi 2 MnO 3 ·(1−d)LiMO 2 and LiMPO 4 , where 0<d<1, and M includes one or more selected from Fe, Ni, Co, and Mn; and the shell contains a crystalline inorganic substance having a full width at half maximum of the main peak of 0-3° as measured by means of X-ray diffraction, and the crystalline inorganic substance includes one or more selected from a metal oxide and an inorganic salt.

First claim

What is claimed is:

1 . A positive electrode active material comprising:
an inner core comprising at least one of a ternary material, dLi 2 MnO 3 ·(1−d)LiMO 2 and LiMPO 4 , where 0<d<1, and M includes one or more selected from Fe, Ni, Co, and Mn; and a shell comprising a crystalline inorganic substance, the crystalline inorganic substance having a full width at half maximum of the main peak of 0-3° as measured by means of X-ray diffraction, and the crystalline inorganic substance including one or more selected from a metal oxide and an inorganic salt.

2 . The positive electrode active material according to claim 1 , wherein the shell comprises at least one of the metal oxide and the inorganic salt, and carbon.

3 . The positive electrode active material according to claim 1 , wherein the inner core comprises LiMPO 4 , and M includes Mn and a non-Mn element, wherein the non-Mn element satisfies at least one of the following conditions:
the ionic radius a of the non-Mn element and the ionic radius b of manganese element satisfy that |a−b|/b is not greater than 10%; the valence alternation voltage U of the non-Mn element satisfies 2 V<U<5.5 V; the chemical activity of a chemical bond formed by the non-Mn element and O is not less than that of a P—O bond; and the highest valence of the non-Mn element is not greater than 6.

4 . The positive electrode active material according to claim 3 , wherein the non-Mn element includes one or two of a first doping element and a second doping element, the first doping element is doped at the manganese site, and the second doping element is doped at the phosphorus site.

5 . The positive electrode active material according to claim 4 , wherein the first doping element satisfies at least one of the following conditions:
the ionic radius a of the first doping element being denoted and the ionic radius b of manganese element satisfy that |a−b|/b is not greater than 10%; and the valence alternation voltage U of the first doping element satisfies 2 V<U<5.5 V.

6 . The positive electrode active material according to claim 4 , wherein the second doping element satisfies at least one of the following conditions:
the chemical activity of a chemical bond formed by the second doping element and oxygen is not less than that of a P—O bond; and the highest valence of the second doping element is not greater than 6.

7 . The positive electrode active material according to claim 4 , wherein the positive electrode active material contains at least two of the first doping elements.

8 . The positive electrode active material according to claim 4 , wherein the first doping element includes one or more elements selected from Zn, Al, Na, K, Mg, Mo, W, Ti, V, Zr, Fe, Ni, Co, Ga, Sn, Sb, Nb and Ge.

9 . The positive electrode active material according to claim 8 , wherein the first doping element includes at least two selected from Fe, Ti, V, Ni, Co, and Mg.

10 . The positive electrode active material according to claim 4 , wherein the second doping element includes one or more elements selected from B (boron), S, Si and N.

11 . The positive electrode active material according to claim 1 , wherein the inner core has a compound with a chemical formula of Li 1+x Mn 1-y A y P 1-z R z O 4 , where x is any numerical value in a range of 0.100-0.100, y is any numerical value in a range of 0.001-0.500, z is any numerical value in a range of 0.001-0.100, A includes one or more elements selected from Zn, Al, Na, K, Mg, Mo, W, Ti, V, Zr, Fe, Ni, Co, Ga, Sn, Sb, Nb, and Ge, and
R includes one or more elements selected from B (boron), S, Si and N.

12 . The positive electrode active material according to claim 11 , wherein the ratio of y to 1−y is 1:10 to 1:1.

13 . The positive electrode active material according to claim 11 , wherein the ratio of z to 1−z is 1:9 to 1:999.

14 . The positive electrode active material according to claim 11 , wherein x is selected from a range of 0.001 to 0.005; and/or, y is selected from a range of 0.01 to 0.5; and/or, z is selected from a range of 0.001 to 0.005; and/or, n is selected from a range of 0.001 to 0.005.

15 . The positive electrode active material according to claim 1 , wherein the inner core has a compound with a chemical formula of Li 1+x C m Mn 1-y A y P 1-z R z O 4-n D n ,
where C includes one or more elements selected from Zn, Al, Na, K, Mg, Nb, Mo and W, A includes one or more elements selected from Zn, Al, Na, K, Mg, Mo, W, Ti, V, Zr, Fe, Ni, Mg, Co, Ga, Sn, Sb, Nb and Ge, R includes one or more elements selected from B (boron), S, Si and N, D includes one or more elements selected from S, F, Cl and Br, and x is any numerical value in a range of 0.100-0.100, y is any numerical value in a range of 0.001-0.500, z is any numerical value in a range of 0.001-0.100, n is any numerical value in a range of 0.001 to 0.1, and m is any numerical value in a range of 0.9 to 1.1.

16 . The positive electrode active material according to claim 15 , wherein C, R and D are each independently any element within the respective ranges above, and A is at least two elements within the range thereof.

17 . The positive electrode active material according to claim 1 , wherein the lattice change rate of the positive electrode active material is 8% or less.

18 . The positive electrode active material according to claim 1 , wherein the Li/Mn antisite defect concentration of the positive electrode active material is 4% or less.

19 . The positive electrode active material according to claim 1 , wherein the surface oxygen valency of the positive electrode active material is −1.89 to −1.98.

20 . The positive electrode active material according to claim 1 , wherein the positive electrode active material has a compacted density under 3 T of 2.0 g/cm 3 or more.

21 . The positive electrode active material according to claim 1 , wherein the crystalline inorganic substance includes a pyrophosphate of QP 2 O 7 and a phosphate of XPO 4 , and the metal oxide includes Q′ e O f , where:
Q and X are each independently selected from one or more of Li, Fe, Ni, Mg, Co, Cu, Zn, Ti, Ag, Zr, Nb or Al;
Q′ is selected from one or more elements of Li, Fe, Ni, Mg, Co, Cu, Zn, Ti, Ag, Zr, Nb and Al;
M′ is selected from one or more elements of an alkali metal, an alkaline earth metal, a transition metal, a group IIIA element, a group IVA element, a lanthanide and Sb;
e is greater than 0 and less than or equal to 2; and
f is greater than 0 and less than or equal to 5.

22 . The positive electrode active material according to claim 21 , wherein the pyrophosphate includes Li a QP 2 O 7 and/or Q b (P 2 O 7 ) c , where 0≤a≤2, 1≤b≤4, 1≤c≤6, the values of a, b, and c satisfy the condition of keeping the Li a QP 2 O 7 or Q b (P 2 O 7 ) c electrically neutral, and Q in the Li a QP 2 O 7 and Q b (P 2 O 7 ) c is each independently selected from one or more elements of Fe, Ni, Mg, Co, Cu, Zn, Ti, Ag, Zr, Nb, or Al.

23 . The positive electrode material according to claim 21 , wherein:
the phosphate has an interplanar spacing of 0.244-0.425 nm, and an included angle of crystal orientation (111) of 20.00°-37.00°; and the pyrophosphate has an interplanar spacing of 0.293-0.470 nm.

24 . The positive electrode active material according to claim 21 , wherein the pyrophosphate and the phosphate each independently have a crystallinity of 10% to 100%.

25 . The positive

Assignees

• Contemporary Amperex Technology Co Ltd

Inventors

• Jiang Yao
• Ouyang Chuying
• Zhang Xinxin
• Deng Bin
• Wang Zhiqiang
• Yuan Tianci
• Xu Bo
• Chen Shangdong

Classifications

• C01G45/22

  Compounds containing manganese, with or without oxygen or hydrogen, and containing two or more other elements · CPC title

• H01M2004/028

  Positive electrodes · CPC title

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• H01M4/625

  Carbon or graphite · CPC title

• H01M4/525

  of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy · CPC title