Electrode and Secondary Battery Including the Same

Patent metadata

Field	Value
Publication number	US-2022158195-A1
Application number	US-202017598617-A
Country	US
Kind code	A1
Filing date	Sep 28, 2020
Priority date	Oct 4, 2019
Publication date	May 19, 2022
Grant date	—

Abstract

An electrode includes an electrode active material layer, wherein the electrode active material layer includes an electrode active material and a conductive agent, wherein the conductive agent includes a first conductive agent and a second conductive agent, wherein the first conductive agent includes a secondary particle in which a plurality of graphene sheets are arranged in different directions and a portion of one graphene sheet is connected to a portion of adjacent another graphene sheet, the second conductive agent includes a carbon nanotube structure in which 2 to 5,000 single-walled carbon nanotube units are bonded to each other, and the carbon nanotube structure is included in an amount of 0.01 wt % to 0.5 wt % in the electrode active material layer. A secondary battery including the electrode is also provided.

First claim

1 . An electrode comprising an electrode active material layer,
wherein the electrode active material layer comprises an electrode active material and a conductive agent, wherein the conductive agent comprises a first conductive agent and a second conductive agent, wherein the first conductive agent comprises a secondary particle in which a plurality of graphene sheets are arranged in different directions and a portion of one graphene sheet is connected to a portion of adjacent another graphene sheet, the second conductive agent comprises a carbon nanotube structure in which 2 to 5,000 single-walled carbon nanotube units are bonded to each other, and the carbon nanotube structure is included in an amount of 0.01 wt % to 0.5 wt % in the electrode active material layer.

2 . The electrode of claim 1 , wherein a weight ratio of the secondary particle to the carbon nanotube structure is in a range of 100:1 to 100:200.

3 . The electrode of claim 1 , wherein the secondary particle is included in an amount of 0.01 wt % to 1.0 wt % in the electrode active material layer.

4 . The electrode of claim 1 , wherein the carbon nanotube structures are interconnected in the electrode to form a network structure.

5 . The electrode of claim 1 , wherein the single-walled carbon nanotube units are arranged side by side and bonded in the carbon nanotube structure.

6 . The electrode of claim 1 , wherein the carbon nanotube structure has an average length of 1 μm to 500 μm.

7 . (canceled)

8 . The electrode of claim 1 , wherein the carbon nanotube structure has an average diameter of 2 nm to 200 nm.

9 . The electrode of claim 1 , wherein the carbon nanotube structure has an average diameter of 50 nm to 120 nm.

10 . The electrode of claim 1 , wherein the single-walled carbon nanotube unit has an average diameter of 0.5 nm to 5 nm.

11 . The electrode of claim 1 , wherein an oxygen content of the secondary particle is in a range of 1 wt % to 10 wt % based on a total weight of the secondary particle.

12 . The electrode of claim 1 , wherein the carbon nanotube structure is a carbon nanotube structure in which 50 to 4,000 single-walled carbon nanotube units are bonded to each other.

13 . The electrode of claim 1 , wherein the graphene sheet has a lateral size of 10 nm to 500 nm.

14 . The electrode of claim 1 , wherein the secondary particle has a D/G peak ratio of 0.9 to 2.0 during Raman spectrum measurement.

15 . The electrode of claim 1 , wherein the secondary particle has a value calculated by Equation 1 of 0 to 0.2:



b
-
a



a

[

Equation
⁢

⁢
1

]

wherein, in Equation 1, a is a specific surface area (m 2 /g) of the secondary particle which is measured by a nitrogen adsorption Brunauer-Emmett-Teller (BET) method, and b is an iodine adsorption value (mg/g) of the secondary particle.

16 . The electrode of claim 1 , wherein the secondary particle further comprises a connection portion connected to at least a part of the graphene sheets of the plurality of graphene sheets,
wherein the connection portion has a non-graphene shape.

17 . The electrode of claim 16 , wherein at least a portion of each of the plurality of graphene sheets is connected to the connection portion.

18 . The electrode of claim 1 , wherein the graphene sheet has an average thickness of 0.34 nm to 10 nm.

19 . The electrode of claim 1 , wherein the secondary particle has a specific surface area (m 2 /g) measured by a nitrogen adsorption BET method of 200 m 2 /g to 1,100 m 2 /g.

20 . The electrode of claim 1 , wherein the electrode is a positive electrode.

21 . A secondary battery comprising the electrode of claim 1 .

Assignees

• Lg Energy Solution Ltd

Inventors

• Kim Tae Gon
• Park Sin Young
• Lee Bo Ram
• Cho Hyung Man
• Yoo Tae Gu
• Kwak Min

Classifications

• H01M10/0525

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

• H01M4/625 Primary

  Carbon or graphite · CPC title

• H01M2004/021

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

• H01M2004/028

  Positive electrodes · CPC title

• H01M4/13

  Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof · CPC title