Positive Electrode and Secondary Battery Including the Same

Patent metadata

Field	Value
Publication number	US-2024387818-A1
Application number	US-202218696039-A
Country	US
Kind code	A1
Filing date	Oct 7, 2022
Priority date	Oct 8, 2021
Publication date	Nov 21, 2024
Grant date	—

Abstract

A positive electrode includes a positive electrode current collector and a positive electrode active material layer disposed on at least one surface of the positive electrode current collector. The positive electrode active material layer includes a positive electrode active material and a conductive material. The conductive material includes a linear conductive material. The positive electrode active material includes a lithium composite transition metal oxide containing nickel (Ni), cobalt (Co), and manganese (Mn). The lithium composite transition metal oxide is in the form of a single particle. The positive electrode active material has an average particle diameter (D 50 ) of 2 μm to 10 μm. The positive electrode satisfies a specific equation for a BET specific surface area and an amount of the positive electrode active material and the linear conductive material.

First claim

1 . A positive electrode comprising:
a positive electrode current collector; and a positive electrode active material layer disposed on at least one surface of the positive electrode current collector, wherein the positive electrode active material layer comprises a positive electrode active material and a conductive material, the conductive material comprises a linear conductive material, the positive electrode active material comprises a lithium composite transition metal oxide containing nickel (Ni), cobalt (Co), and manganese (Mn), the lithium composite transition metal oxide is in the form of a single particle, the positive electrode active material has an average particle diameter (D 50 ) of 2 μm to 10 μm, and the positive electrode satisfies Equation 1 below:

1.2
≤

B
/
A

≤
4.7

[

Equation
⁢

1

]

wherein in Equation 1 above, A is a product of a BET specific surface area of the positive electrode active material and a percentage by weight of the positive electrode active material relative to a weight of the positive electrode active material layer, and B is a product of a BET specific surface area of the linear conductive material and a percentage by weight of the linear conductive material relative to a weight of the positive electrode active material layer.

2 . The positive electrode of claim 1 , wherein the positive electrode active material layer comprises the positive electrode active material in an amount of 90 wt % to 99 wt %.

3 . The positive electrode of claim 1 , wherein the positive electrode active material has a specific surface area of 0.2 m 2 /g to 3 m 2 /g.

4 . The positive electrode of claim 1 , wherein the linear conductive material comprises is carbon nanotubes.

5 . The positive electrode of claim 1 , wherein the conductive material consists of the linear conductive material.

6 . The positive electrode of claim 1 , wherein the linear conductive material has the specific surface area of 150 m 2 /g to 300 m 2 /g.

7 . The positive electrode of claim 1 , wherein the linear conductive material has a pellet density of 0.09 g/cc to 0.16 g/cc.

8 . The positive electrode of claim 1 , wherein the positive electrode active material layer comprises the linear conductive material in an amount of 0.50 wt % to 1.75 wt %.

9 . The positive electrode of claim 1 , wherein the BET specific surface area of the linear conductive material is 150 to 450 times the BET specific surface area of the positive electrode active material.

10 . The positive electrode of claim 1 , wherein a percentage by weight of the linear conductive material relative to a total weight of the positive electrode active material layer is 0.006 to 0.018 times a percentage by weight of the positive electrode active material relative to a total weight of the positive electrode active material layer.

11 . The positive electrode of claim 1 , wherein the positive electrode active material layer further comprises a binder.

12 . The positive electrode of claim 11 , wherein the positive electrode active material layer comprises the binder in a remaining amount excluding the positive electrode active material and the linear conductive material.

13 . A secondary battery comprising:
the positive electrode according to claim 1 ; a negative electrode facing the positive electrode; a separator interposed between the positive electrode and the negative electrode; and an electrolyte.

Assignees

• Lg Energy Solution Ltd

Inventors

• Cho Woo Hyung
• Heo Min Ji
• Park Sung Bin

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

• H01M4/625

  Carbon or graphite · CPC title

• H01M4/505

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