Bonding agent used in lithium-ion battery
A bonding agent includes: structural units represented by Formula I, Formula II, Formula III, and Formula IV: where each of R 1 , R 2 , R 3 , and R 4 is independently selected from the group consisting of hydrogen, and C 1-8 straight-chain or branched alkyl groups substituted or not substituted by a substituting group, each of R 5 , R 6 , and R 7 is independently selected from the group consisting of hydrogen, and C 1-6 straight-chain or branched alkyl groups substituted or not substituted by a substituting group, R 8 is selected from C 1-15 alkyl groups substituted or not substituted by a substituting group, each of R 9 , R 10 , and R 11 is independently selected from the group consisting of hydrogen, and C 1-6 straight-chain or branched alkyl groups substituted or not substituted by a substituting group.
1. A bonding agent, the bonding agent being a polymer comprising:
at least four different structural units represented by each of Formula I, Formula II, Formula III, and Formula IV:
wherein each of R 1 , R 2 , R 3 , and R 4 is independently selected from the group consisting of hydrogen, and C 1-8 straight-chain or branched alkyl groups substituted by a substituting group or not substituted by a substituting group, wherein each of R 5 , R 6 , and R 7 is independently selected from the group consisting of hydrogen, and C 1-6 straight-chain or branched alkyl groups substituted by a substituting group or not substituted by a substituting group,
wherein R 8 is selected from C 1-15 alkyl groups substituted by a substituting group or not substituted by a substituting group,
wherein each of R 9 , R 10 , and R 11 is independently selected from the group consisting of hydrogen, and C 1-6 straight-chain or branched alkyl groups substituted by a substituting group or not substituted by a substituting group, and
wherein the substituting group is selected from halogens, and wherein each of n 1 , n 2 , n 3 and n 4 is independently an integer greater than 0, and wherein:
a molar percent of the structural units represented by Formula I in the bonding agent is 50% to 90%;
a molar percent of the structural units represented by Formula II in the bonding agent is 0.1% to 20%;
a molar percent of the structural units represented by Formula III in the bonding agent is 1% to 25%;
a molar percent of the structural units represented by Formula IV in the bonding agent is 0.1% to 10%.
2. The bonding agent of claim 1 , wherein:
the molar percent of the structural units represented by Formula I in the bonding agent is 60% to 75%;
the molar percent of the structural units represented by Formula II in the bonding agent is 5% to 10%;
the molar percent of the structural units represented by Formula III in the bonding agent is 10% to 25%;
the molar percent of the structural units represented by Formula IV in the bonding agent is 3% to 5%.
3. The bonding agent of claim 1 , wherein, in Formula II, each of R 1 , R 2 , R 3 , and R 4 is independently selected from the group consisting of hydrogen, and C 1-6 straight-chain or branched alkyl groups.
4. The bonding agent of claim 3 , wherein, in Formula II, each of R 1 , R 2 , R 3 , and R 4 is independently selected from the group consisting of hydrogen and C 1-3 alkyl groups.
5. The bonding agent of claim 1 , wherein, in Formula III, each of R 5 , R 6 , and R 7 is independently selected from the group consisting of hydrogen and C 1-3 alkyl groups, wherein R 8 is selected from C 1-12 alkyl groups substituted by the substituting group or not substituted by the substituting group.
6. The bonding agent of claim 5 , wherein, in Formula III, each of R 5 , R 6 , and R 7 is independently selected from the group consisting of hydrogen, methyl, and trifluoromethyl, wherein R 8 is selected from the group consisting of methyl, ethyl, n-butyl, isobutyl, sec-butyl, t-butyl, n-propyl, cyclohexyl, C 12 alkyl, 2-ethylhexyl, isobornyl, trifluoroethyl, and trifluoromethyl.
7. The bonding agent of claim 1 , wherein, in Formula IV, each of R 9 , R 10 , and R 11 is independently selected from the group consisting of hydrogen and C 1-3 alkyl groups.
8. The bonding agent of claim 7 , wherein, in Formula IV, each of R 9 , R 10 , and R 11 is independently selected from the group consisting of hydrogen, methyl, and trifluoromethyl.
9. The bonding agent of claim 1 , wherein a number average molecular weight of the bonding agent is 500,000 to 1.2 million.