Gel polymer electrolyte and lithium secondary battery comprising the same
View Patent ↗Provided are a gel polymer electrolyte including a polymer network, and an electrolyte solution impregnated in the polymer network, wherein the polymer network is formed by combining a first oligomer, which includes unit A derived from a monomer including at least one copolymerizable acrylate or acrylic acid, unit C including urethane, and unit E including siloxane, in a three-dimensional structure, and a lithium secondary battery including the gel polymer electrolyte.
1. A gel polymer electrolyte comprising:
a polymer network; and
an electrolyte solution impregnated in the polymer network,
wherein the polymer network is formed by combining a first oligomer represented by Formula 1, which includes unit A derived from a monomer including at least one copolymerizable acrylate or acrylic acid, unit C including urethane, and unit E including siloxane, in a three-dimensional structure,
A-[C-E] k -C-A [Formula 1]
where k is an integer of 1 to 200.
2. The gel polymer electrolyte of claim 1 , wherein unit A is a unit derived from at least one compound selected from the group consisting of hydroxymethyl(meth)acrylate and hydroxyethyl(meth)acrylate, or a unit represented by Formula (i):
wherein unit C comprises a unit represented by Formula 2a or Formula 2b:
where R′ is at least one selected from the group consisting of a linear or non-linear alkylene group having 1 to 10 carbon atoms, a substituted or unsubstituted cycloalkylene group having 3 to 10 carbon atoms, a substituted or unsubstituted bicycloalkylene group having 6 to 20 carbon atoms, a substituted or unsubstituted arylene group having 6 to 20 carbon atoms, a substituted or unsubstituted biarylene group having 6 to 20 carbon atoms, a naphthalene group, and an anthracene group;
wherein unit E comprises a unit represented by Formula 3:
where R 1 and R 2 are a linear or non-linear alkylene group having 1 to 5 carbon atoms,
R 3 and R 4 are each independently one selected from the group consisting of hydrogen, an alkyl group having 1 to 5 carbon atoms, and a phenyl group,
R 5 to R 10 are each independently one selected from the group consisting of hydrogen, an alkyl group having 1 to 5 carbon atoms, a phenyl group, and fluorine,
O is an integer of 0 or 1,
P is an integer of 0 to 400,
r is an integer of 1 to 400, and
a molar ratio of p:r is in a range of 0:100 to 80:20.
3. The gel polymer electrolyte of claim 2 , wherein R′ is a compound selected from the group consisting of groups below:
4. The gel polymer electrolyte of claim 2 , wherein unit E comprises at least one compound selected from the group consisting of Formulae 3a to 3g:
where P is 0 or an integer of 1 to 400,
r is an integer of 1 to 400, and
a molar ratio of p:r is in a range of 0:100 to 80:20.
5. The gel polymer electrolyte of claim 1 , wherein an amount of unit A is 1 mol or 2 mols in 1 mol of the first oligomer, and a molar ratio of unit C:unit E is in a range of 1.005:1 to 2:1.
6. The gel polymer electrolyte of claim 1 , wherein the first oligomer selectively further comprises at least one unit selected from the group consisting of unit B represented by Formula 4 and unit D represented by Formula 5:
*—CO—R″—O—* [Formula 4]
*—O—[R′″—O] m —* [Formula 5]
where R″ is a substituted or unsubstituted linear alkylene group having 1 to 10 carbon atoms, or a substituted or unsubstituted non-linear alkylene group having 1 to 10 carbon atoms,
R′″ is a substituted or unsubstituted linear alkylene group having 1 to 10 carbon atoms, or a substituted or unsubstituted non-linear alkylene group having 1 to 10 carbon atoms, and
m is an integer of 1 to 30.
7. The gel polymer electrolyte of claim 6 , wherein unit B is at least one compound selected from the group consisting of groups below:
*—CO—CH 2 CH 2 —O—* (B-i)
*—CO—CHCH 3 CH 2 —O—* (B-ii)
*—CO—CH 2 CH 2 CH 2 CH 2 CH 2 —O—* (B-iii)
*—CO—CHCH 3 CH 2 CH 2 —O—* (B-iv), and
wherein unit D is at least one compound selected from the group consisting of groups below:
*—O—CH 2 CH 2 —O—* (D-i)
*—O—CHCH 3 CH 2 —O—* (D-ii).
8. The gel polymer electrolyte of claim 6 , wherein an amount of unit A is 1 mol or 2 mols in 1 mol of the first oligomer, and
a molar ratio of unit B:unit C:unit D:unit E is in a range of 0 to 35:2 to 201:0 to 35:1 to 200 (where unit B and unit D are not 0 at a same time).
9. The gel polymer electrolyte of claim 6 , wherein the first oligomer is at least one compound selected from the group consisting of Formulae 7a to 7d:
where k is an integer of 1 to 200,
n is an integer of 1 to 30,
m is an integer of 1 to 30,
P is an integer of 1 to 400,
r is an integer of 1 to 400, and
a molar ratio of p:r is in a range of 0:100 to 80:20.
10. The gel polymer electrolyte of claim 1 , further comprising a second oligomer which includes a unit derived from at least one selected from the group consisting of methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, butyl acrylate, butyl methacrylate, hexyl acrylate, hexyl methacrylate, ethylhexyl acrylate, ethylhexyl methacrylate, 2,2,2-trifluoroethyl acrylate, 2,2,2-trifluoroethyl methacrylate, 2,2,3,3-tetrafluoropropyl acrylate, and 2,2,3,3-tetrafluoropropyl methacrylate.
11. The gel polymer electrolyte of claim 10 , wherein the second oligomer is included in an amount of 50 wt % or less based on a total amount of the first oligomer.
12. The gel polymer electrolyte of claim 1 , wherein the polymer network further contains inorganic particles in the polymer network.
13. A composition for a gel polymer electrolyte, the composition comprising:
a lithium salt;
an electrolyte solution solvent;
a polymerization initiator; and
a first oligomer represented by Formula 1, which includes unit A derived from a monomer including at least one copolymerizable acrylate or acrylic acid, unit C including urethane, and unit E including siloxane,
A-[C-E] k -C-A [Formula 1]
where k is an integer of 1 to 200.
14. The composition for a gel polymer electrolyte of claim 13 , wherein the first oligomer is included in an amount of 0.5 wt % to 20 wt % based on a total weight of the composition for a gel polymer electrolyte.
15. The composition for a gel polymer electrolyte of claim 13 , wherein unit A is a unit derived from at least one compound selected from the group consisting of hydroxymethyl(meth)acrylate and hydroxyethyl(meth)acrylate, or a unit represented by Formula (i):
wherein unit C comprises a unit represented by Formula 2a or Formula 2b:
where R′ is at least one selected from the group consisting of a linear or non-linear alkylene group having 1 to 10 carbon atoms, a substituted or unsubstituted cycloalkylene group having 3 to 10 carbon atoms, a substituted or unsubstituted bicycloalkylene group having 6 to 20 carbon atoms, a substituted or unsubstituted arylene group having 6 to 20 carbon atoms, a substituted or unsubstituted biarylene group having 6 to 20 carbon atoms, a naphthalene group, and an anthracene group; and
wherein unit E comprises a unit represented by Formula 3:
where R 1 and R 2 are a linear or non-linear alkylene group having 1 to 5 carbon atoms,
R 3 and R 4 are each independently one selected from the group consisting of hydrogen, an alkyl group having 1 to 5 carbon atoms, and a phenyl group,
R 5 to R 10 are each independently one selected from the group consisting of hydrogen, an alkyl group having 1 to 5 carbon atoms, a phenyl group, and fluorine,
O is an integer of 0 or 1,
P is an integer of 0 to 400,
r is an integer of 1 to 400, and
a molar ratio of p:r is in a range of 0:100 to 80:20.
16. The composition for a gel polymer electrolyte of claim 13 , wherein an amount of unit A is 1 mol or 2 mols in 1 mol of the first oligomer, and a molar ratio of unit C:unit E is in a range of 1.005:1 to 2:1.
17. The composition for a gel polymer electrolyte of claim 13 , wherein the first oligomer selectively further comprises at least one unit selected from the group consisting of unit B represented by Formula 4 and unit D represented by Formula 5:
*—CO—R″—O—* [Formula 4]
*—O—[R′″—O] m —* [Formula 5]
where R″ is a substituted or unsubstituted linear alkylene group having 1 to 10 carbon atoms, or a substituted or unsubstituted non-linear alkylene group having 1 to 10 carbon atoms,
R′″ is a substituted or unsubstituted linear alkylene group having 1 to 10 carbon atoms, or a substituted or unsubstituted non-linear alkylene group having 1 to 10 carbon atoms, and
m is an integer of 1 to 30.
18. The composition for a gel polymer electrolyte of claim 17 , wherein an amount of unit A is 1 mol or 2 mols in 1 mol of the oligomer, an
a molar ratio of unit B:unit C:unit D:unit E is in a range of 0 to 35:2 to 201:0 to 35:1 to 200 (where unit B and unit D are not 0 at a same time).
19. The composition for a gel polymer electrolyte of claim 17 , wherein the first oligomer is at least one compound selected from the group consisting of Formulae 7a to 7d:
where k is an integer of 1 to 200,
n is an integer of 1 to 30,
m is an integer of 1 to 30,
P is an integer of 1 to 400,
r is an integer of 1 to 400, and
a molar ratio of p:r is in a range of 0:100 to 80:20.
20. The composition for a gel polymer electrolyte of claim 13 , wherein the polymer network further contains inorganic particles in the polymer network.
21. A lithium secondary battery comprising:
a positive electrode and a negative electrode capable of intercalating and deintercalating lithium; and
a polymer electrolyte disposed between the positive electrode and the negative electrode,
wherein the polymer electrolyte comprises the gel polymer electrolyte of claim 1 .