Positive Electrode for Lithium Secondary Battery and Lithium Secondary Battery Including the Same

Patent metadata

Field	Value
Publication number	US-2023402597-A1
Application number	US-202118034991-A
Country	US
Kind code	A1
Filing date	Dec 24, 2021
Priority date	Dec 24, 2020
Publication date	Dec 14, 2023
Grant date	—

Abstract

A positive electrode for a lithium secondary battery includes a positive electrode active material layer including: a first positive electrode active material represented by Formula 1 and having a crystalline size of 150 nm or more; a conductive agent including single-walled carbon nanotubes (SWCNTs); and a binder. A lithium secondary battery includes the positive electrode.

First claim

1 . A positive electrode for a lithium secondary battery comprising a positive electrode active material layer including:
a first positive electrode active material represented by Formula 1 below, wherein the first positive electrode active material has a crystalline size of 150 nm or more;
Li x1 [Ni a1 Co b1 M 1 c1 M 2 d1 ]O 2   [Formula 1]

wherein, in Formula 1 above, M 1 is Mn, Al, or a combination thereof, M 2 is at least one selected from the group consisting of Zr, B, W, Mg, Ce, Hf, Ta, La, Ti, Sr, Ba, F, P, and S, and 0.9≤x1≤1.1, 0.8≤a1<1, 0<b1<0.2, 0<c1<0.2, 0≤d1≤0.1, a conductive agent including single-walled carbon nanotubes; and a binder.

2 . The positive electrode for a lithium secondary battery of claim 1 , wherein the first positive electrode active material has a crystalline size of 150 nm to 200 nm.

3 . The positive electrode for a lithium secondary battery of claim 1 , wherein the first positive electrode active material has an average particle diameter D 50 of 10 μm to 20 μm.

4 . The positive electrode for a lithium secondary battery of claim 1 , wherein the positive electrode active material layer further includes a second positive electrode active material having an average particle diameter D 50 of 1 μm to 8 μm.

5 . The positive electrode for a lithium secondary battery of claim 4 , wherein the second positive electrode active material is represented by Formula 2 below, wherein the second positive electrode active material has a crystalline size of 90 nm to 160 nm:
Li x2 [Ni a2 Co b2 M 3 c2 M 4 d2 ]O 2   [Formula 1]
wherein, in Formula 2, M 3 is Mn, Al, or a combination thereof, M 4 is at least one selected from the group consisting of Zr, B, W, Mg, Ce, Hf, Ta, La, Ti, Sr, Ba, F, P, and S, and 0.9≤x2≤1.1, 0.6≤a2≤0.90, 0<b2<0.40, 0<c2<0.40, and 0≤d2≤0.1.

6 . The positive electrode for a lithium secondary battery of claim 4 , wherein the first positive electrode active material and the second positive electrode active material are included at a weight ratio of 50:50 to 95:5.

7 . The positive electrode for a lithium secondary battery of claim 1 , wherein the single-walled carbon nanotubes have a specific surface area of 700 m 2 /g to 1,500 m 2 /g.

8 . The positive electrode for a lithium secondary battery of claim 1 , wherein the conductive agent further includes at least one of graphite, carbon black, a conductive fiber, metal powder, a conductive whisker, or a conductive metal oxide.

9 . The positive electrode for a lithium secondary battery of claim 1 , wherein the single-walled carbon nanotubes are included in an amount of 0.01 wt % to 2 wt % based on a total weight of the positive electrode active material layer.

10 . A lithium secondary battery comprising the positive electrode for a lithium secondary battery of claim 1 .

Assignees

• Lg Energy Solution Ltd

Inventors

• Kim Hyeong Ii
• Kim Hak Yoon
• Baek So Ra
• Hur Hyuck
• Kim Dong Hwi
• Chae Seul Ki
• Jung Wang Mo
• Lee Dong Hun

Classifications

• 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

• H01M10/052

  Li-accumulators · CPC title

• H01M2004/028

  Positive electrodes · CPC title

• H01M4/364

  as mixtures · CPC title

• H01M4/625

  Carbon or graphite · CPC title