Positive electrode and lithium battery including the same

Patent metadata

Field	Value
Publication number	US-11575128-B2
Application number	US-201916675359-A
Country	US
Kind code	B2
Filing date	Nov 6, 2019
Priority date	Dec 21, 2018
Publication date	Feb 7, 2023
Grant date	Feb 7, 2023

Abstract

A positive electrode includes a composite material including a positive active material and a coating layer on a surface of the positive active material, wherein the coating layer includes a copolymer including a first repeating unit represented by Formula 1 below and a second repeating unit represented by Formula 2 below:

wherein Ar 1 , R 1 to R 6 , A, A 1 ,

Y − , m, and n are the same as defined in the specification.

First claim

What is claimed is:

1. A positive electrode for a lithium battery comprising:
a composite material comprising
a positive active material as a core of the composite material, and
a coating layer located on a surface of the positive active material forming a shell on the core of the composite material,

wherein the coating layer has a thickness of about 0.1 nanometer to about 100 nanometers; and
wherein the coating layer comprises a copolymer comprising a first repeating unit represented by Formula 1, and a second repeating unit represented by Formula 2:

wherein in Formula 1,
Ar 1 is a substituted or unsubstituted C6-C30 arylene group or a substituted or unsubstituted C6-C30 heteroarylene group,
R 1 , R 2 , and R 3 are each independently hydrogen, a substituted or unsubstituted C1-C30 alkyl group, a substituted or unsubstituted C6-C30 aryl group, or a substituted or unsubstituted C3-C30 heteroaryl group,
A is a bond, a substituted or unsubstituted C1-C30 alkylene group, a substituted or unsubstituted C6-C30 arylene group, a substituted or unsubstituted C3-C30 heteroarylene group, a substituted or unsubstituted C4-C30 cycloalkylene group, or a substituted or unsubstituted C3-C30 heterocycloalkylene group,

is a 3-membered to 31-membered ring system comprising 2 to 30 carbon atoms, and X is —S, —N(R), or —P(R′),
R and R′ are each independently hydrogen, a substituted or unsubstituted C1-C30 alkyl group, a substituted or unsubstituted C1-C30 heteroalkyl group, a substituted or unsubstituted C1-C30 alkoxy group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C7-C30 arylalkyl group, a substituted or unsubstituted C6-C30 aryloxy group, a substituted or unsubstituted C3-C30 heteroaryl group, a substituted or unsubstituted C4-C30 heteroarylalkyl group, a substituted or unsubstituted C3-C30 cycloalkyl group, a substituted or unsubstituted C2-C30 alkenyl group, or a substituted or unsubstituted C3-C30 alkynyl group, and
Y − is an anion,

wherein in Formula 2,
A l is a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C2-C30 heteroaryl group, or —C(═O)O—(CH 2 CH 2 O) a —R 7 , wherein R 7 is hydrogen, a substituted or unsubstituted C1-C30 alkyl group, or a substituted or unsubstituted C6-C30 aryl group, and a is an integer of 1 to 10, and
R 4 , R 5 , and R 6 are each independently hydrogen, a substituted or unsubstituted C1-C30 alkyl group, a substituted or unsubstituted C6-C30 aryl group, or a substituted or unsubstituted C3-C30 heteroaryl group, and
in Formulae 1 and 2, m and n are mole fractions of the first repeating unit represented by Formula 1 and the second repeating unit represented by Formula 2, respectively, wherein a sum of m and n is 1, and m and n are each independently greater than 0 and less than 1.

2. The positive electrode of claim 1 , wherein Ar 1 of Formula 1 comprises a phenylene group, a biphenylene group, a naphthalenylene group, a phenanthrenylene group, a triphenlylenylene group, an anthracenylene group, a fluorenylene group, or a carbazolylene group.

3. The positive electrode of claim 1 , wherein Ar 1 of Formula 1 is one of the groups represented by Formula 3-1, Formula 3-2, Formula 3-3, Formula 3-3, Formula 3-4, or Formula 3-5 below:

wherein in Formula 3-1, Formula 3-2, Formula 3-3, Formula 3-4, and Formula 3-5, * is a point of attachment, and R 11 to R 20 are each independently hydrogen, a substituted or unsubstituted C1-C30 alkyl group, a substituted or unsubstituted C6-C30 aryl group, or a substituted or unsubstituted C3-C30 heteroaryl group.

4. The positive electrode of claim 1 , wherein

of Formula 1 comprises a group represented by Formula 4-1, Formula 4-2, Formula 4-3, Formula 4-4, or Formula 4a:

wherein in Formula 4-1, Formula 4-2, Formula 4-3, and Formula 4-4, Z is S, N, or P, and Ru to R 25 are each independently hydrogen, a substituted or unsubstituted C1-C30 alkyl group, a substituted or unsubstituted C1-C30 alkoxy group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C6-C30 aryloxy group, a substituted or unsubstituted C3-C30 heteroaryl group, a substituted or unsubstituted C3-C30 heteroaryloxy group, a substituted or unsubstituted C4-C30 cycloalkyl group, or a substituted or unsubstituted C3-C30 heterocycloalkyl group,
wherein R 11 is absent when Z is S,

wherein in Formula 4a, R 22 to R 26 are defined the same as R 11 to R 25 of Formula 4-1, Formula 4-2, Formula 4-3, Formula 4-4, and Z is N.

5. The positive electrode of claim 1 , wherein

of Formula 1 comprises a group represented by Formula 5-1 or Formula 5-2, and
Y − in Formula 1 comprises BF 4 − , PF 6 − , AsF 6 − , SbF 6 − , AlCl 4 − , HSO 4 − , CH 3 SO 3 − , (CF 3 SO 2 ) 2 N − , C 1 − , Br − , I, SO 4 −2 , ClO 4 − , CF 3 SO 3 − , CF 3 CO 2 − , (C 2 F 5 SO 2 ) 2 N − , (C 2 F 5 SO 2 )(CF 3 SO 2 )N − , (FSO 2 ) 2 N − , NO 3 , Al 2 C 7 − , CH 3 COO − , (CF 3 SO 2 ) 3 C − , (CF 3 ) 2 PF 4 − , (CF 3 ) 3 PF 3 − , (CF 3 ) 4 PF 2 − , (CF 3 ) 5 PF − , (CF 3 ) 6 P − , SF 5 CF 2 SO 3 − , SF 5 CHFCF 2 SO 3 − , CF 3 CF 2 (CF 3 ) 2 C − , (CF 3 SO 2 ) 2 CH − , (SF 5 ) 3 C − , (O(CF 3 ) 2 C 2 (CF 3 ) 2 O) 2 PO − , or a combination thereof:

wherein in Formula 5-1 and Formula 5-2, R 20 to R 28 are each independently hydrogen, a substituted or unsubstituted C1-C30 alkyl group, a substituted or unsubstituted C1-C30 alkoxy group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C6-C30 aryloxy group, a substituted or unsubstituted C3-C30 heteroaryl group, a substituted or unsubstituted C3-C30 heteroaryloxy group, a substituted or unsubstituted C4-C30 cycloalkyl group, or a substituted or unsubstituted C3-C30 heterocycloalkyl group.

6. The positive electrode of claim 1 , wherein an amount of the copolymer in the coating layer is from about 0.1 parts by weight to about 10 parts by weight, based on 100 parts by weight of a total weight of the positive electrode.

7. The positive electrode of claim 1 , wherein the copolymer comprises a random copolymer.

8. The positive electrode of claim 1 , wherein a molar ratio of m to n in Formula 1 is from about 2:8 to about 5:5.

9. The positive electrode of claim 1 , wherein the copolymer has a degree of polymerization of about 10 to about 5,000.

10. The positive electrode of claim 1 , wherein the copolymer is represented by Formula 6 below, and has a degree of polymerization of about 10 to about 5,000:

Assignees

• Samsung Electronics Co Ltd
• Samsung Sdi Co Ltd
• Samsung Sdi Co Ld

Inventors

• Choi Hongsoo
• Gwon Hyeokjo
• Kim Soyeon
• Kim Hyunseok
• Chang Wonseok

Classifications

• H01M4/366 Primary

  as layered products · CPC title

• C08F212/08 Primary

  Styrene · CPC title

• H01M4/382 Primary

  Lithium (H01M4/405 takes precedence) · CPC title

• H01M4/628

  Inhibitors, e.g. gassing inhibitors, corrosion inhibitors · CPC title

• H01M4/13 Primary

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