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

Patent metadata

Field	Value
Publication number	US-12159996-B2
Application number	US-202117211650-A
Country	US
Kind code	B2
Filing date	Mar 24, 2021
Priority date	Mar 25, 2020
Publication date	Dec 3, 2024
Grant date	Dec 3, 2024

Abstract

A lithium secondary battery includes a positive electrode including a positive electrode active material, a negative electrode, and an electrolyte located therebetween. The positive electrode active material includes a lithium cobalt-based active material and a lithium nickel cobalt-based active material, wherein the lithium cobalt-based active material is larger in size and amount than the lithium nickel cobalt-based active material, and the lithium nickel cobalt-based active material is a one-body positive electrode active material.

First claim

What is claimed is:

1. A positive electrode active material comprising:
a lithium cobalt-based active material; and
a lithium nickel cobalt-based active material,
wherein:
the lithium cobalt-based active material is larger in size and amount than the lithium nickel cobalt-based active material, and
the lithium nickel cobalt-based active material is a one-body active material primarily composed of one-body particles each being produced by increasing a size of a primary particle and each of the one-body particles being present in independent phase without being morphologically agglomerated with other one-body particles,
the lithium cobalt-based active material is a one-body active material primarily composed of one-body particles each being produced by increasing a size of a primary particle and each of the one-body particle being present in independent phase without being morphologically agglomerated with other one-body particles, and
the lithium nickel cobalt-based active material is a compound represented by Formula 8:
Li x CO a Ni b Al c O 2   Formula 8

wherein, in Formula 8, 0.9<x<1.2, 0<a≤0.09, 0.6≤b<1, 0<c≤0.01, and a+b+c=1.

2. The positive electrode active material of claim 1 , wherein:
an average particle diameter of the lithium cobalt-based active material is 10 μm to 20 μm, and
an average particle diameter of the lithium nickel cobalt-based active material is 3 μm to 8 μm.

3. The positive electrode active material of claim 1 , wherein the lithium cobalt-based active material is a compound represented by Formula 1, a compound represented by Formula 2, or a combination thereof:
Li x Co 1-y M y A 2   Formula 1

wherein, in Formula 1, 0.9≤x≤1.2, and 0≤y≤0.5,
M is Mn, Mg, Ca, Sr, Ba, Ti, Zr, Nb, Mo, W, Zn, Al, Si, Cr, Fe, V, a rare earth element, or a combination thereof, and
A is O, F, S, P, or a combination thereof, and
Li x Co 1-y M y O 2-z X z   Formula 2

wherein, in Formula 2, 0.9≤x≤1.2, 0≤y≤0.5, and 0≤z≤0.5,
M is Mn, Mg, Ca, Sr, Ba, Ti, Zr, Nb, Mo, W, Zn, Al, Si, Cr, Fe, V, a rare earth element, or a combination thereof, and
X is F, S, P, or a combination thereof.

4. The positive electrode active material of claim 1 , wherein the lithium cobalt-based active material is a compound represented by Formula 5:
Li x CO a O 2+α   Formula 5

wherein, in Formula 5, 0.9≤x≤1.2, 0.98≤a≤1.00, and −0.1≤α≤0.1.

5. The positive electrode active material of claim 1 ,
wherein:
the lithium cobalt-based active material is LiCoO 2 , and
the lithium nickel cobalt-based active material is the compound represented by Formula 8, and the compound represented by Formula 8 is LiNi 0.9 Co 0.09 Al 0.01 O 2 , Li 1.05 Ni 0.9 Co 0.09 Al 0.01 O 2 , or a combination thereof.

6. A positive electrode comprising a positive electrode active material including:
a lithium cobalt-based active material; and
a lithium nickel cobalt-based active material,
wherein:
the lithium cobalt-based active material is larger in size and amount than the lithium nickel cobalt-based active material, and
the lithium nickel cobalt-based active material is a one-body active material primarily composed of one-body particles each being produced by increasing a size of a primary particle and each of the one-body particle being present in independent phase without being morphologically agglomerated with other one-body particles,
the lithium nickel cobalt-based active material is a compound represented by Formula 8:
Li x CO a Ni b Al c O 2   Formula 8

wherein, in Formula 8, 0.9<x<1.2, 0<a≤0.09, 0.6≤b<1, 0<c≤0.01, and a+b+c=1.

7. The positive electrode of claim 6 , wherein the positive electrode has a mixture density of 4.1 g/cc or greater.

8. The positive electrode of claim 6 , wherein an average particle diameter of the lithium cobalt-based active material is 10 μm to 20 μm, and
an average particle diameter of the lithium nickel cobalt-based active material is 3 μm to 8 μm.

9. The positive electrode of claim 6 , wherein the lithium cobalt-based active material is a one-body active material.

10. The positive electrode of claim 6 , wherein the lithium cobalt-based active material is a compound represented by Formula 1, a compound represented by Formula 2, or a combination thereof:
Li x Co 1-y M y A 2   Formula 1

wherein, in Formula 1, 0.9≤x≤1.2, and 0≤y≤0.5,
M is Mn, Mg, Ca, Sr, Ba, Ti, Zr, Nb, Mo, W, Zn, Al, Si, Cr, Fe, V, a rare earth element, or a combination thereof, and
A is O, F, S, P, or a combination thereof, and
Li x Co 1-y M y O 2-z X z   Formula 2

wherein, in Formula 2, 0.9≤x≤1.2, 0≤y≤0.5, and 0≤z≤0.5,
M is Mn, Mg, Ca, Sr, Ba, Ti, Zr, Nb, Mo, W, Zn, Al, Si, Cr, Fe, V, a rare earth element, or a combination thereof, and
X is F, S, P, or a combination thereof.

11. The positive electrode of claim 6 , wherein the lithium cobalt-based active material is a compound represented by Formula 5:
Li x CO a O 2+α   Formula 5

wherein, in Formula 5, 0.9≤x≤1.2, 0.98≤a≤1.00, and −0.1≤α≤0.1.

12. The positive electrode of claim 6 , wherein:
the lithium cobalt-based active material is LiCoO 2 , and
the lithium nickel cobalt-based active material is LiNi 0.9 Co 0.09 Al 0.01 O 2 , Li 1.05 Ni 0.9 Co 0.09 Al 0.01 O 2 , or a combination thereof.

13. A lithium secondary battery comprising:
the positive electrode of claim 6 ,
a negative electrode, and
an electrolyte therebetween.

14. A positive electrode comprising a positive electrode active material including:
a lithium cobalt-based active material; and
a lithium nickel cobalt-based active material,
wherein:
the lithium cobalt-based active material is larger in size and amount than the lithium nickel cobalt-based active material,
the lithium nickel cobalt-based active material is a one-body active material, and
the positive electrode has a mixture density of 4.1 g/cc or greater.

15. A positive electrode active material comprising:
a lithium cobalt-based active material; and
a lithium nickel cobalt-based active material,
wherein:
the lithium cobalt-based active material is larger in size and amount than the lithium nickel cobalt-based active material, and
the lithium nickel cobalt-based active material is a one-body active material comprising one-body particles each being produced by increasing a size of a primary particle and each of the one-body particle being present in independent phase without being morphologically agglomerated with other one-body particles, the lithium cobalt-based active material is a one-body active material comprising one-body particles each being produced by increasing a size of a primary particle and each of the one-body particle being present in independent phase without being morphologically agglomerated with other one-body particles, and
the lithium nickel cobalt-based active material is LiNi 0.9 Co 0.09 Mn 0.01 O 2 , Li 1.05 Ni 0.9 Co 0.09 Mn 0.01 O 2 , or a combination thereof.

Assignees

• Samsung Sdi Co Ltd

Inventors

• Yang Mihwa
• Cho Moonju
• Kim Minjae
• Kim Beomkwon

Classifications

• 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

• H01M4/505

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

• Y02E60/10

  Energy storage using batteries · CPC title

• C01P2004/03

  obtained by SEM · CPC title