Positive electrode active material for lithium secondary batteries, positive electrode for lithium secondary batteries, and lithium secondary battery

Patent metadata

Field	Value
Publication number	US-2019334170-A1
Application number	US-201716472161-A
Country	US
Kind code	A1
Filing date	Dec 21, 2017
Priority date	Dec 26, 2016
Publication date	Oct 31, 2019
Grant date	—

Abstract

A positive electrode active material for lithium secondary batteries includes a lithium composite metal compound containing secondary particles that are aggregates of primary particles which are capable of being doped or dedoped with lithium ions and satisfies all of specific requirements (1) to (4)

First claim

1 . A positive electrode active material for lithium secondary batteries including a lithium composite metal compound containing secondary particles that are aggregates of primary particles which are capable of being doped or dedoped with lithium ions, the positive electrode active material for lithium secondary batteries satisfying all of the following requirements (1) to (4),
(1) the lithium composite metal compound has a crystal structure of α-NaFeO 2 type which is represented by Composition Formula (A) described below,
Li[Li x (Ni a Co b Mn c M d ) 1-x ]O 2   (A)

(in Composition Formula (A), −0.1≤x≤0.2, 0.7≤a<1, 0<b≤0.3, 0≤c≤0.2, 0≤d≤0.1 and a+b+c+d=1 are satisfied, and M represents one or more elements selected from the group consisting of Mg, Ca, Sr, Ba, Zn, B, Al, Ga, Ti, Zr, Ge, Fe, Cu, Cr, V, W, Mo, Sc, Y, La, Nb, Ta, Tc, Ru, Rh, Pd, Ag, Cd, In, and Sn), (2) when the positive electrode active material for lithium secondary batteries is measured in powder X-ray diffraction measurement using CuKα radiation, a ratio A/B of an integrated intensity A of a peak within a range of 2θ=18.7±1° and an integrated intensity B of a peak within a range of 2θ=44.4±1° is 1.2 or more, (3) lithium carbonate included the positive electrode active material for lithium secondary batteries with respect to a total mass of the positive electrode active material for lithium secondary batteries is 0.7 mass % or less and lithium hydroxide included the positive electrode active material for lithium secondary batteries with respect to a total mass of the positive electrode active material for lithium secondary batteries is 0.7 mass % or less, and (4) a moisture content of the positive electrode active material for lithium secondary batteries with respect to a total mass of the positive electrode active material for lithium secondary batteries is 1000 ppm or less.

2 . The positive electrode active material for lithium secondary batteries according to claim 1 , wherein x in Composition Formula (A) is 0<x<0.1.

3 . The positive electrode active material for lithium secondary batteries according to claim 1 , wherein a BET specific surface area of the positive electrode active material for lithium secondary batteries is 0.1 m 2 /g or more and 2 m 2 /g or less.

4 . The positive electrode active material for lithium secondary batteries according to claim 1 , wherein
in a 10% cumulative particle diameter (D 10 ), a 50% cumulative particle diameter (D 50 ), and a 90% cumulative particle diameter (D 90 ) obtained from values of a particle size distribution measurement of the positive electrode active material for lithium secondary batteries, the 50% cumulative particle diameter (D 50 ) is 5 μm or more and 20 μm or less, and Equation (B) shown below is satisfied,
0.8≤( D 90 −D 10 )/ D 50 ≤1.5  (B).

5 . The positive electrode active material for lithium secondary batteries according to claim 1 , wherein a tap density of the positive electrode active material for lithium secondary batteries is 1.5 cc/g or more and 3.5 cc/g or less.

6 . The positive electrode active material for lithium secondary batteries according to claim 1 , further comprising at least one of a covering particle and a covering layer formed of lithium containing metal composite oxide containing Li and X (X is one or more element selected from the group consisting of B, Al, Ti, Zr, La, and W) on a surface of the primary particle or secondary particle of the lithium composite metal compound.

7 . The positive electrode active material for lithium secondary batteries according to claim 1 , further comprising a covering particle or a covering layer formed of lithium containing metal composite oxide containing Li and X (X is one or more element selected from the group consisting of B, Al, Ti, Zr, La, and W) on a surface of the primary particle or secondary particle of the lithium composite metal compound.

8 . The positive electrode active material for lithium secondary batteries according to claim 6 , wherein a proportion ({X/(Ni+Co+Mn+M)}×100) which is an atomic ratio of X in the covering particle or the covering layer with respect to a sum of the atomic ratio of Ni, Co, Mn, and M in the positive electrode active material for lithium secondary batteries is 0.05 mol % or more and 5 mol % or less.

9 . The positive electrode active material for lithium secondary batteries according to claim 6 , wherein the covering particle or the covering layer comprises at least one of LiAlO 2 .

10 . The positive electrode active material for lithium secondary batteries according to claim 6 , wherein the covering particle or the covering layer comprises at least one of Li 2 WO 4 and Li 3 WO 5 .

11 . A positive electrode for lithium secondary batteries comprising the positive electrode active material for lithium secondary batteries according to claim 1 .

12 . A lithium secondary batteries comprising the positive electrode for lithium secondary batteries according to claim 11 .

13 . The positive electrode active material for lithium secondary batteries according to claim 2 , wherein a BET specific surface area of the positive electrode active material for lithium secondary batteries is 0.1 m 2 /g or more and 2 m 2 /g or less.

14 . The positive electrode active material for lithium secondary batteries according to claim 2 , wherein
in a 10% cumulative particle diameter (D 10 ), a 50% cumulative particle diameter (D 50 ), and a 90% cumulative particle diameter (D 90 ) obtained from values of a particle size distribution measurement of the positive electrode active material for lithium secondary batteries, the 50% cumulative particle diameter (D 50 ) is 5 μm or more and 20 μm or less, and Equation (B) shown below is satisfied,
0.8≤( D 90 −D 10 )/ D 50 ≤1.5  (B).

15 . The positive electrode active material for lithium secondary batteries according to claim 2 , wherein a tap density of the positive electrode active material for lithium secondary batteries is 1.5 cc/g or more and 3.5 cc/g or less.

16 . The positive electrode active material for lithium secondary batteries according to any one of claim 2 , further comprising at least one of a covering particle and a covering layer formed of lithium containing metal composite oxide containing Li and X (X is one or more element selected from the group consisting of B, Ai, Ti, Zr, La, and W) on a surface of the primary particle or secondary particle of the lithium composite metal compound.

17 . The positive electrode active material for lithium secondary batteries according to claim 2 , further comprising a covering particle or a covering layer formed of lithium containing metal composite oxide containing Li and X (X is one or more element selected from the group consisting of B, Al, Ti, Zr, La, and W) on a surface of the primary particle or secondary particle of the lithium composite metal compound.

18 . The positive electrode active material for lithium secondary batteries according to claim 16 , wherein a proportion ({X/(Ni+Co+Mn+M)}×100) which is an atomic ratio of X in the covering particle or the covering layer with respect to a sum of the atomic ratio of Ni, Co, Mn, and M in the positive electrode active material for lithium secondary batteries is 0.05 mol % or more and 5 mol % or less.

19 . The positive electrode active material for lithium secondary batteries according to claim 16 , wherein the covering particle or the covering layer comprises at least one of LiAlO 2 .

20 . The positive electrode active mat

Assignees

• Sumitomo Chemical Co
• Tanaka Chemical Corp

Inventors

• Takamori Kenji
• Imanari Yuichiro
• Maeda Yusuke

Classifications

• H01M10/052

  Li-accumulators · CPC title

• H01M4/525 Primary

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

• C01G53/50 Primary

  of the type (MnO2)n-, e.g. Li(NixMn1-x)O2 or Li(MyNixMn1-x-y)O2 · CPC title

• H01M4/364

  as mixtures · CPC title

• H01M4/505

  of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy · CPC title