Separator for lithium secondary battery, method for manufacturing same, and lithium secondary battery comprising same
A separator for a lithium secondary battery, a method for manufacturing the same and a lithium secondary battery comprising the same, where the separator includes a porous polymer substrate having a plurality of pores and a polymer coating layer on at least one surface of the porous polymer substrate. The polymer coating layer comprises a thermosetting phenol-containing resin having at least one hydroxyl group and at least one aromatic ring. A coating amount of the thermosetting phenol-containing resin is 0.01 g/m 2 to 3 g/m 2 of the porous polymer substrate based on one polymer coating layer.
1. A separator for a lithium secondary battery, comprising:
a porous polymer substrate having a plurality of pores; and
a polymer coating layer on at least one surface of the porous polymer substrate,
wherein the polymer coating layer comprises a thermosetting phenol-containing resin having at least one hydroxyl group and at least one aromatic ring, and
a coating amount of the thermosetting phenol-containing resin is 0.01 g/m 2 to 3 g/m 2 of the porous polymer substrate based on one polymer coating layer,
wherein the thermosetting phenol-containing resin is configured to be thermally cured at 120° C. to 200° C. in the separator to form a network structure, and
wherein the separator does not comprise inorganic particles.
2. The separator for the lithium secondary battery according to claim 1 , wherein the thermosetting phenol-containing resin comprises at least one of a novolac-containing phenol resin represented by Formula 1 or a resol-containing phenol resin represented by Formula 2:
in the Formula 1, n is an integer of 1 or greater, and R is any one of H, alkyl, alkoxy and alkenyl group having 1 to 100 carbon atoms,
wherein the alkyl, alkoxy and alkenyl group having 1 to 100 carbon atoms are optionally substituted,
in the Formula 2, each of n and m is an integer of 1 or greater, and R is any one of H, alkyl, alkoxy and alkenyl group having 1 to 100 carbon atoms,
wherein the alkyl, alkoxy and alkenyl group having 1 to 100 carbon atoms are optionally substituted.
3. The separator for the lithium secondary battery according to claim 1 , wherein the thermosetting phenol-containing resin is a phenol-formaldehyde resin.
4. The separator for the lithium secondary battery according to claim 1 , wherein the coating amount of the thermosetting phenol-containing resin is 0.05 g/m 2 to 2.5 g/m 2 of the porous polymer substrate based on one polymer coating layer.
5. The separator for the lithium secondary battery according to claim 1 , wherein the coating amount of the thermosetting phenol-containing resin is 0.35 g/m 2 to 2.1 g/m 2 of the porous polymer substrate based on one polymer coating layer.
6. The separator for the lithium secondary battery according to claim 1 , wherein the porous polymer substrate comprises a porous polymer film comprising at least one of polyethylene or polypropylene.
7. A lithium secondary battery, comprising:
a positive electrode,
a negative electrode, and
a separator interposed between the positive electrode and the negative electrode,
wherein the separator is defined in claim 1 .
8. A method for manufacturing a separator for a lithium secondary battery, comprising:
(S1) preparing a polymer solution comprising a thermosetting phenol-containing resin having at least one hydroxyl group and at least one aromatic ring is dissolved in a solvent; and
(S2) coating the polymer solution on at least one surface of a porous polymer substrate, wherein a coating amount of the thermosetting phenol-containing resin is 0.01 g/m 2 to 3 g/m 2 of the porous polymer substrate based on one polymer coating layer and drying the coated polymer solution to form a polymer coating layer,
wherein the thermosetting phenol-containing resin is configured to be thermally cured at 120° C. to 200° C. in the separator to form a network structure, and
wherein the separator does not comprise inorganic particles.
9. The method for manufacturing the separator for the lithium secondary battery according to claim 8 , wherein the thermosetting phenol-containing resin comprises at least one of a novolac-containing phenol resin represented by Formula 1 or a resol-containing phenol resin represented by Formula 2:
in the Formula 1, n is an integer of 1 or greater, and R is any one of H, alkyl, alkoxy and alkenyl group having 1 to 100 carbon atoms,
wherein the alkyl, alkoxy and alkenyl group having 1 to 100 carbon atoms are optionally substituted,
in the Formula 2, each of n and m is an integer of 1 or greater, and R is any one of H, alkyl, alkoxy and alkenyl group having 1 to 100 carbon atoms,
wherein the alkyl, alkoxy and alkenyl group having 1 to 100 carbon atoms are optionally substituted.
10. The method for manufacturing the separator for a lithium secondary battery according to claim 8 , wherein the coating amount of the thermosetting phenol-containing resin is 0.05 g/m 2 to 2.5 g/m 2 of the porous polymer substrate based on one polymer coating layer.
11. The method for manufacturing the separator for a lithium secondary battery according to claim 8 , wherein the coating amount of the thermosetting phenol-containing resin is 0.35 g/m 2 to 2.1 g/m 2 of the porous polymer substrate based on one polymer coating layer.