Current collector

Patent metadata

Field	Value
Publication number	US-2026031364-A1
Application number	US-202318995650-A
Country	US
Kind code	A1
Filing date	Aug 2, 2023
Priority date	Aug 2, 2022
Publication date	Jan 29, 2026
Grant date	—

Abstract

Disclosed is a current collector, and a method for using the current collector. The current collector is capable of forming an electrode, which does not affect performance and operation of a secondary battery by exhibiting, in a normal state, excellent electrical characteristics including low resistance, and can ensure stability by blocking, in an abnormal state, energization of an electrode assembly through resistance increase. The current collector is also capable of ensuring excellent adhesive force between layers forming the electrode.

First claim

1 . A current collector comprising:
a current collector body; and a polymer layer on at least one side of the current collector body, wherein the polymer layer comprises a conductive copolymer, and wherein an adhesive force of adhesion of the polymer layer to the current collector body is 20 gf/20 mm or more.

2 . A current collector comprising:
a current collector body; and a polymer layer on at least one side of the current collector body, wherein the polymer layer comprises a conductive copolymer comprising a polar functional group, and wherein the polar functional group comprises one group selected from the group consisting of a carboxyl group, a hydroxy group, an amino group, a cyano group, a nitro group, an ether group, and a functional group of Formula 3 below:

where L 4 is a single bond, an alkylene group or an alkylidene group, L 3 is an alkylene group or an alkylidene group, R 5 is hydrogen or an alkyl group, and n is a number in a range of 1 to 10.

3 . The current collector according to claim 2 , wherein the conductive copolymer has an EP value in a range of 6,000 to 20,000, the EP value being determined according to Equation A:

EP
=

Mn
/
P

[

Equation
⁢

A

]

where the EP value is a relationship of Mn and P, where Mn is a number average molecular weight of the conductive copolymer, and P is a mole number of monomer units containing the polar functional group in the conductive copolymer.

4 . The current collector according to claim 1 , wherein the conductive copolymer has a number average molecular weight in a range of 5,000 g/mol to 100,000 g/mol.

5 . The current collector according to claim 1 , wherein a DC resistance of the current collector is 10,000 Ω·cm or less at 25° C.

6 . The current collector according to claim 1 , wherein an AC impedance resistance of the current collector is 1,000Ω or less.

7 . The current collector according to claim 1 , wherein a ΔR 1 of the current collector is 100 Ω·cm/° C. or more, the ΔR 1 being determined according to the Equation 1:

Δ
⁢
R
⁢
1

=

Max
⁢

{

(

R

n
+
5

⁢

R
n

)

/
5

}

[

Equation
⁢

1

]

where R n is a DC resistance at any temperature n° C. within a temperature range of 25° C. to 135° C., and R n+5 is a DC resistance at a temperature ((n+5° C.)) 5° C. higher than the temperature n° C., and Max {(R n+5 /R n )/5} is a maximum value among (R n+5 /R n )/5 values confirmed within the temperature range of 25° C. to 135° C.

8 . The current collector according to claim 7 , wherein a temperature of R n at which the ΔR 1 is identified is more than 80° C.

9 . The current collector according to claim 1 , wherein a ΔR 2 of the current collector is 10 Ω/° C. or more, the ΔR 21 being determined according to the Equation 2:

Δ
⁢
R
⁢
2

=

Max
⁢

{

(

R

z
+
5

/

R
z

)

/
5

}

[

Equation
⁢

2

]

where R z is an AC impedance resistance at any temperature n° C. within a temperature range of 25° C. to 135° C., and R z+5 is an AC impedance resistance at a temperature ((n+5° C.)) 5° C. higher than the temperature n° C., and Max {(R z+5 /R z )/5} is a maximum value among (R z+5 /R z )/5 values confirmed within the temperature range of 25° C. to 135° C.

10 . The current collector according to claim 9 , wherein a temperature of R z at which the ΔR 2 is identified is 80° C. or more.

11 . The current collector according to claim 2 , wherein the conductive copolymer further comprises a long-chain hydrocarbon functional group.

12 . The current collector according to claim 11 , wherein a ratio M1/M2 of a mole number M1 of the long-chain hydrocarbon functional group relative to a mole number M2 of the polar functional group in the conductive copolymer is in a range of 1.5 to 20.

13 . The current collector according to claim 1 , wherein the conductive copolymer comprises a monomer unit of Formula 1:

Assignees

• Lg Chemical Ltd
• Lg Energy Solution Ltd

Inventors

• Kang Joon Koo
• Kwon Soon Ho
• Kim Ki Hwan
• Park Eun Kyoung
• Song In Taek
• Koh Jong Kwan
• Park Sung Bin
• Kim Min Gyu
• Cho Woo Hyung

Classifications

• C08G2261/514

  Electron transport · CPC title

• C08G2261/3247

  containing combinations of different heteroatoms other than nitrogen and oxygen or nitrogen and sulfur · CPC title

• C08G2261/3223

  containing one or more sulfur atoms as the only heteroatom, e.g. thiophene · CPC title

• C08G2261/1424

  containing ether groups, including alkoxy · CPC title

• C08G2261/122

  statistical · CPC title