Positive electrode material for lithium secondary battery, and positive electrode for lithium secondary battery and lithium secondary battery including the same

Patent metadata

Field	Value
Publication number	US-12080877-B2
Application number	US-201917047884-A
Country	US
Kind code	B2
Filing date	May 22, 2019
Priority date	May 23, 2018
Publication date	Sep 3, 2024
Grant date	Sep 3, 2024

Abstract

A positive electrode material for a lithium secondary battery includes a first positive electrode active material and a second positive electrode active material, both of which are lithium composite transition metal oxides containing transition metals. The first positive electrode active material has a larger average particle size (D 50 ) than the second positive electrode active material, wherein a ratio (Li/Me) 1 of the mole number of lithium with respect to the total mole number of transition metals of the first positive electrode active material is more than 1 to 1.5 or less, and a ratio (Li/Me) 2 of the mole number of lithium (Li) with respect to the total mole number of transition metals of the second positive electrode active material is 0.9 to 1. The second positive electrode active material has a crystallite size of 180 nm or more.

First claim

The invention claimed is:

1. A positive electrode material for a lithium secondary battery, comprising:
a first positive electrode active material and a second positive electrode active material, wherein the first positive electrode active material and the second positive electrode active material are lithium composite transition metal oxides containing transition metals comprising nickel (Ni), cobalt (Co) and manganese (Mn),
an average particle size (D 50 ) of the first positive electrode active material is larger than an average particle size (D 50 ) of the second positive electrode active material,
a ratio (Li/Me) 1 of a mole number of lithium with respect to a total mole number of transition metals of the first positive electrode active material is more than 1 to 1.5 or less,
a ratio (Li/Me) 2 of a mole number of lithium (Li) with respect to a total mole number of transition metals of the second positive electrode active material is 0 .9 to 1,
and the second positive electrode active material has a crystallite size of 180 nm or more, wherein the second positive electrode active material is a secondary particle formed by agglomerating primary particles, and an average particle size (D 50 ) of the primary particle is 0.6 μm or more
and wherein the first positive electrode active material is represented by Formula 1 below:
Li 1+p1 [Ni 1−(x1+y1+z1) Co x1 Mn y1 M a z1 ] 1−p1 O 2   [Formula 1]

Where M a is at least one or more elements selected from the group consisting of Ba, Ca, Zr, Ti, Mg, Ta, Nb, Al, Cr and Mo, and
0<p1≤0.2, 0<x1≤0.5, 0<y1≤0.5, 0≤z1≤0.1, and 0<x1+y1+z1≤0.7.

2. The positive electrode material according to claim 1 , wherein the crystallite size of the second positive electrode active material is from 180 to 450 nm.

3. The positive electrode material according to claim 1 , wherein the average particle size (D 50 ) of the second positive electrode active material is 8 μm or less.

4. The positive electrode material according to claim 1 , wherein the average particle size (D 50 ) of the first positive electrode active material is 9 to 20 μm.

5. The positive electrode material according to claim 1 , wherein the second positive electrode active material is represented by Formula 2 below:
Li 1+p2 [Ni 1−(x2+y2+z2) Co x2 Mn y2 M b z2 ] 1−p2 O 2   [Formula 2]

where M b is at least one or more elements selected from the group consisting of Ba, Ca, Zr, Ti, Mg, Ta, Nb, Al, Cr and Mo, and
−0.05≤p2≤0, 0<x2≤0.5, 0<y2≤0.5, 0≤z2≤0.1, and 0<x2+y2+z2≤0.7.

6. The positive electrode material according to claim 1 , wherein the first positive electrode active material and the second positive electrode active material are mixed in a weight ratio of 60:40 to 85:15.

7. A positive electrode for a lithium secondary battery, comprising the positive electrode material for a lithium secondary battery according to claim 1 .

8. A lithium secondary battery comprising the positive electrode for a lithium secondary battery according to claim 7 .

Assignees

• Lg Chemical Ltd
• Lg Energy Solution Ltd

Inventors

• Kim Dong Hwi
• Lee Dong Hun
• Jung Wang Mo
• Park Sung Bin
• Han Gi Beom

Classifications

• H01M2004/028

  Positive electrodes · CPC title

• H01M2004/021

  Physical characteristics, e.g. porosity, surface area · CPC title

• H01M10/0525

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

• H01M4/505

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