Separator including coating layer with ethylenically unsaturated binder, and secondary battery including polymer network formed by gel polymer electrolyte and ethylenically unsaturated binder in coating layer of separator
The present invention relates to a separator for a secondary battery, the separator including a substrate and a coating layer formed on the surface of the substrate, wherein the coating layer includes an organic binder and inorganic particles, and the organic binder contains an ethylenically unsaturated group, and to a lithium secondary battery including the same.
1 . A separator for a lithium secondary battery, the separator comprising:
a substrate; and
a coating layer formed on a surface of the substrate, wherein
the coating layer includes an organic binder and inorganic particles, and
the organic binder contains an ethylenically unsaturated group positioned at an end portion or a side portion of a polymer including at least one unit selected from the group consisting of Formulas X-1, X-2, and X-4:
in Formula X-1, the ml is an integer of 1 to 100,
in Formula X-2, the m2 and the m3 are each independently an integer of 1 to 100,
in Formula X-4, the m5 is an integer of 1 to 100,
wherein the ethylenically unsaturated group is at least one selected from the group consisting of a vinyl group, an acryloxy group and a methacryloxy group, and
wherein the inorganic particles is included in an amount of 60 parts by weight to 99 parts by weight based on 100 parts by weight of the coating layer.
2 . The separator of claim 1 , wherein the thickness of the separator is in a range of 0.1 to 20 μm.
3 . The separator of claim 1 , wherein the substrate include a non-woven fabric comprising at least one of polymer resins selected from the group consisting of polyolefin, polyethylene, polyethylene terephthalate, polybutylene terephthalate, polyacetal, polyamide, polycarbonate, polyimide, polyetheretherketone, polyethersulfone, poloxylene oxide, polyphenylenesulfide, and polyethylene naphthalene, or a laminate of two or more thereof.
4 . The separator of claim 1 , wherein the substrate include a porous polymer film comprising at least one of polymer resins selected from the group consisting of polyolefin, polyethylene, polyethylene terephthalate, polybutylene terephthalate, polyacetal, polyamide, polycarbonate, polyimide, polyetheretherketone, polyethersulfone, poloxylene oxide, polyphenylenesulfide, and polyethylene naphthalene, or a laminate of two or more thereof.
5 . The separator of claim 1 , wherein the inorganic particles include at least one selected from the group consisting of SiO 2 , Al 2 O 3 , TiO 2 , ZrO 2 , SnO 2 , CeO 2 , MgO, CaO, ZnO, Y 2 O 3 , Pb(Zr,Ti)O 3 (PZT), Pb (1-a1) La a1 Zr (1-b) Ti b1 O 3 wherein 0≤a1≤1, 0≤b1≤1, PLZT, PB(Mg 3 Nb 2/3 )O 3 -PbTiO 3 (PMN-PT), BaTiO 3 , HfO 2 (hafnia), and SrTiO 3 .
6 . The separator of claim 1 , wherein the inorganic particles is included in an amount of 60 parts by weight to 90 parts by weight based on 100 parts by weight of the coating layer.
7 . The separator of claim 1 , wherein the inorganic particles include at least one selected from the group consisting of Al 2 O 3 , TiO 2 , ZrO 2 , SnO 2 , CeO 2 , MgO, CaO, ZnO, Y 2 O 3 , Pb(Zr, Ti)O 3 (PZT), Pb (1-a1) La a1 Zr (1-b1) Ti b1 O 3 wherein 0≤a1, 0≤b1≤1, PLZT, PB(Mg 3 Nb 2/3 )O 3 -PbTiO 3 (PMN-PT), BaTiO 3 , HfO 2 (hafnia), and SrTiO 3 .
8 . The separator of claim 1 , wherein the organic binder is included in an amount of 1 part by weight to 40 parts by weight based on 100 parts by weight of the coating layer.
9 . The separator of claim 1 , wherein the ethylenically unsaturated group comprises a vinyl group.
10 . The separator of claim 1 , wherein the ethylenically unsaturated group comprises
an acryloxy group.
11 . The separator of claim 1 , wherein the ethylenically unsaturated group comprises a methacryloxy group.
12 . The separator of claim 1 , wherein the organic binder is included in an amount of 5 parts by weight to 40 parts by weight based on 100 parts by weight of the coating layer.
13 . The separator of claim 1 , wherein the organic binder is included in an amount of 20 parts by weight to 40 parts by weight based on 100 parts by weight of the coating layer.