Binder for rechargeable lithium battery, electrode for rechargeable lithium battery, method of preparing electrode for rechargeable lithium battery and rechargeable lithium battery including electrode
A binder for a rechargeable lithium battery includes a copolymer having a weight average molecular weight of about 10,000 to about 500,000 and including a repeating unit represented by Chemical Formula X and a repeating unit represented by Chemical Formula Y-1: The binder may be used in preparing an electrode for a rechargeable lithium battery and a rechargeable lithium battery including the electrode exhibits improved stability, rate capability, and cycle-life.
1. A binder for a rechargeable lithium battery, comprising
a copolymer including a repeating unit represented by Chemical Formula X and a repeating unit represented by Chemical Formula Y-1, and having a weight average molecular weight of about 10,000 to about 500,000:
wherein in Chemical Formula X:
R 1 to R 4 are each independently selected from hydrogen, a substituted or unsubstituted C1 to C20 alkyl group, and a substituted or unsubstituted C6 to C30 aryl group,
L is a substituted or unsubstituted C2 to C10 alkenylene group, and
n is 0 or 1,
and wherein in Chemical Formula Y-1:
R 5 and R 6 are each independently selected from hydrogen and a substituted or unsubstituted C1 to C20 alkyl group, and
R 7 is selected from an unsubstituted C7 to C20 alkyl group; a substituted or unsubstituted C2 to C10 alkenyl group; a substituted or unsubstituted C2 to C10 alkynyl group; a substituted or unsubstituted C1 to C10 alkoxy group; a substituted or unsubstituted C3 to C10 cycloalkyl group; an unsubstituted C6 to C30 aryl group; a substituted or unsubstituted C1 to C30 heteroaryl group; a C1 to C20 alkyl group substituted with a C2 to C30 alkenyl group, a C2 to C30 alkynl group, a C1 to C10 alkylsilyl group, a C3 to C30 cycloalkyl group, a C6 to C30 aryl group, a C1 to C30 heteroaryl group, a C1 to C10 alkoxy group, a silane group, an alkylsilane group, an alkoxysilane group, or a halogen; and a C6 to C30 aryl group substituted with a C1 to C30 alkyl group, a C2 to C30 alkenyl group, a C2 to C30 alkynyl group, a C1 to C10 alkylsilyl group, a C3 to C30 cycloalkyl group, a C6 to C30 aryl group, a C1 to C30 heteroaryl group, a C1 to C10 alkoxy group, a silane group, an alkylsilane group, an alkoxysilane group, an amine group, an alkylamine group, an arylamine group, or a halogen.
2. The binder for a rechargeable lithium battery of claim 1 , wherein the copolymer comprises the repeating unit represented by Chemical Formula X and the repeating unit represented by Chemical Formula Y-1 in a mole ratio of about 40:60 to about 60:40.
3. The binder for a rechargeable lithium battery of claim 1 , wherein the binder is aqueous.
4. The binder for a rechargeable lithium battery of claim 1 , wherein the copolymer further comprises a repeating unit represented by Chemical Formula Z:
wherein in Chemical Formula Z:
R 11 is selected from hydrogen and a substituted or unsubstituted C1 to C20 alkyl group, and
R 12 and R 13 are independently selected from hydrogen, a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C2 to C10 alkenyl group, a substituted or unsubstituted C2 to C10 alkynyl group, a substituted or unsubstituted C1 to C10 alkoxy group, a substituted or unsubstituted C3 to C10 cycloalkyl group, a substituted or unsubstituted C6 to C30 aryl group, and a substituted or unsubstituted C1 to C30 heteroaryl group.
5. A binder for a rechargeable lithium battery, comprising
a copolymer including a repeating unit represented by Chemical Formula X, and a repeating unit represented by Chemical Formula Y-1, and having a weight average molecular weight of about 10,000 to about 500,000:
wherein in Chemical Formula X:
R 1 to R 4 are each independently selected from hydrogen, a substituted or unsubstituted C1 to C20 alkyl group, and a substituted or unsubstituted C6 to C30 aryl group,
L is a substituted or unsubstituted C2 to C10 alkenylene group, and
n is 0 or 1;
wherein in Chemical Formula Y-1:
R 5 and R 6 are each independently selected from hydrogen and a substituted or unsubstituted C1 to C20 alkyl group, and
R 7 is selected from an unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C2 to C10 alkenyl group, a substituted or unsubstituted C2 to C10 alkynyl group, a substituted or unsubstituted C1 to C10 alkoxy group, a substituted or unsubstituted C3 to C10 cycloalkyl group, a substituted or unsubstituted C6 to C30 aryl group, and a substituted or unsubstituted C1 to C30 heteroaryl group;
wherein the copolymer further comprises a repeating unit represented by Chemical Formula Z:
wherein in Chemical Formula Z:
R 11 is selected from hydrogen and a substituted or unsubstituted C1 to C20 alkyl group, and
R 12 and R 13 are independently selected from hydrogen, a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C2 to C10 alkenyl group, a substituted or unsubstituted C2 to C10 alkynyl group, a substituted or unsubstituted C1 to C10 alkoxy group, a substituted or unsubstituted C3 to C10 cycloalkyl group, a substituted or unsubstituted C6 to C30 aryl group, and a substituted or unsubstituted C1 to C30 heteroaryl group;
wherein the copolymer comprises:
about 5 mol % to about 35 mol % of the repeating unit represented by Chemical Formula X,
about 5 mol % to about 35 mol % of the repeating unit represented by Chemical Formula Y-1, and
about 30 mol % to about 90 mol % of the repeating unit represented by Chemical Formula Z.
6. The binder for a rechargeable lithium battery of claim 4 , wherein the copolymer further comprises repeating units represented by at least one of the following Chemical Formulas W-1 to W-5:
wherein:
R 21 , R 23 , R 25 , R 27 , and R 30 are each independently selected from hydrogen and a substituted or unsubstituted C1 to C20 alkyl group;
R 22 , R 24 , and R 26 are each independently selected from hydrogen, a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C2 to C20 alkenyl group, a substituted or unsubstituted C2 to C20 alkynyl group, a C3 to C8 cycloalkyl group, a substituted or unsubstituted C6 to C30 aryl group, a substituted or unsubstituted C1 to C30 heteroaryl group, a silane group, a C1 to C20 alkylsilane group, a C1 to C20 alkoxysilane group, a C1 to C20 alkylamine group, a C1 to C20 alkyl group substituted with an alkoxysilane group, and a C1 to C20 alkyl group substituted with an amine group;
R 28 and R 29 are each independently selected from hydrogen, a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C2 to C20 alkenyl group, a substituted or unsubstituted C2 to C20 alkynyl group, a C3 to C8 cycloalkyl group, a substituted or unsubstituted C6 to C30 aryl group, a substituted or unsubstituted C1 to C30 heteroaryl group, a silane group, a C1 to C20 alkylsilane group, a C1 to C20 alkoxysilane group, and a C2 to C20 carbonyl group;
R 28 and R 29 are each linear or are linked as a fused ring;
R 31 and R 32 are each independently selected from hydrogen, a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C2 to C20 alkenyl group, a substituted or unsubstituted C2 to C20 alkynyl group, a C3 to C8 cycloalkyl group, a substituted or unsubstituted C6 to C30 aryl group, a substituted or unsubstituted C1 to C30 heteroaryl group, a silane group, a C1 to C20 alkylsilane group, a C1 to C20 alkoxysilane group, and a C2 to C20 carbonyl group; and
R 31 and R 32 are each linear or are linked as a fused ring.
7. A binder for a rechargeable lithium battery, comprising
a copolymer including a repeating unit represented by Chemical Formula X, and a repeating unit represented by Chemical Formula Y-1, and having a weight average molecular weight of about 10,000 to about 500,000:
wherein in Chemical Formula X:
R 1 to R 4 are each independently selected from hydrogen, a substituted or unsubstituted C1 to C20 alkyl group, and a substituted or unsubstituted C6 to C30 aryl group,
L is a substituted or unsubstituted C2 to C10 alkenylene group, and
n is 0 or 1;
wherein in Chemical Formula Y-1:
R 5 and R 6 are each independently selected from hydrogen and a substituted or unsubstituted C1 to C20 alkyl group, and
R 7 is selected from a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C2 to C10 alkenyl group, a substituted or unsubstituted C2 to C10 alkynyl group, a substituted or unsubstituted C1 to C10 alkoxy group, a substituted or unsubstituted C3 to C10 cycloalkyl group, a substituted or unsubstituted C6 to C30 aryl group, and a substituted or unsubstituted C1 to C30 heteroaryl group;
wherein the copolymer further comprises a repeating unit represented by Chemical Formula Z and repeating units represented by at least one of Chemical Formulas W-1 to W-5:
wherein in Chemical Formula Z:
R 11 is selected from hydrogen and a substituted or unsubstituted C1 to C20 alkyl group, and
R 12 and R 13 are independently selected from hydrogen, a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C2 to C10 alkenyl group, a substituted or unsubstituted C2 to C10 alkynyl group, a substituted or unsubstituted C1 to C10 alkoxy group, a substituted or unsubstituted C3 to C10 cycloalkyl group, a substituted or unsubstituted C6 to C30 aryl group, and a substituted or unsubstituted C1 to C30 heteroaryl group;
wherein in Chemical Formulas W-1 to W-5:
R 21 , R 23 , R 25 , R 27 , and R 30 are each independently selected from hydrogen and a substituted or unsubstituted C1 to C20 alkyl group;
R 22 , R 24 , and R 26 are each independently selected from hydrogen, a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C2 to C20 alkenyl group, a substituted or unsubstituted C2 to C20 alkynyl group, a C3 to C8 cycloalkyl group, a substituted or unsubstituted C6 to C30 aryl group, a substituted or unsubstituted C1 to C30 heteroaryl group, a silane group, a C1 to C20 alkylsilane group, a C1 to C20 alkoxysilane group, a C1 to C20 alkylamine group, a C1 to C20 alkyl group substituted with an alkoxysilane group, and a C1 to C20 alkyl group substituted with an amine group;
R 28 and R 29 are each independently selected from hydrogen, a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C2 to C20 alkenyl group, a substituted or unsubstituted C2 to C20 alkynyl group, a C3 to C8 cycloalkyl group, a substituted or unsubstituted C6 to C30 aryl group, a substituted or unsubstituted C1 to C30 heteroaryl group, a silane group, a C1 to C20 alkylsilane group, a C1 to C20 alkoxysilane group, and a C2 to C20 carbonyl group;
R 28 and R 29 are each linear or are linked as a fused ring;
R 31 and R 32 are each independently selected from hydrogen, a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C2 to C20 alkenyl group, a substituted or unsubstituted C2 to C20 alkynyl group, a C3 to C8 cycloalkyl group, a substituted or unsubstituted C6 to C30 aryl group, a substituted or unsubstituted C1 to C30 heteroaryl group, a silane group, a C1 to C20 alkylsilane group, a C1 to C20 alkoxysilane group, and a C2 to C20 carbonyl group; and
R 31 and R 32 are each linear or are linked as a fused ring;
wherein the copolymer comprises:
about 5 mol % to about 35 mol % of the repeating unit represented by Chemical Formula X,
about 5 mol % to about 35 mol % of the repeating unit represented by Chemical Formula Y-1,
about 20 mol % to about 89 mol % of the repeating unit represented by Chemical Formula Z, and
about 1 mol % to about 10 mol % of at least one of repeating units represented by Chemical Formulas W-1 to W-5.