SEPARATOR FOR RECHARGEABLE BATTERY AND RECHARGEABLE LITHIUM BATTERY INCLUDING THE SAME

1 . A separator for a rechargeable battery, comprising:

a porous substrate and a heat resistance layer on at least one surface of the porous substrate,

wherein the heat resistance layer comprises an acryl-based copolymer, a polyvinyl alcohol-based polymer, and a sheet-shaped inorganic particle,

the sheet-shaped inorganic particle is selected from mica, clay, magnesium hydroxide (Mg(OH) 2 ), aluminum hydroxide (Al(OH) 3 ), talc, and a combination thereof, and

a particle diameter of the sheet-shaped inorganic particle is about 0.1 μm to about 10 μm.

2 . The separator of claim 1 , wherein the acryl-based copolymer comprises a unit derived from (meth)acrylate or (meth)acrylic acid, a cyano group-containing unit, and/or a sulfonate group-containing unit.

3 . The separator of claim 2 , wherein the unit derived from (meth)acrylate or (meth)acrylic acid is represented by Chemical Formula 1, Chemical Formula 2, Chemical Formula 3, or a combination thereof:

wherein, in Chemical Formula 1 to Chemical Formula 3,

R 1 , R 2 , and R 3 are each independently a hydrogen atom or a methyl group, and in Chemical Formula 2, M is an alkali metal.

4 . The separator of claim 2 , wherein the cyano group-containing unit is represented by Chemical Formula 4:

wherein, in Chemical Formula 4,

R 4 is a hydrogen atom or a C1 to C3 alkyl group,

L 1 is —C(═O)—, —C(═O)O—, —OC(═O)—, —O—, or —C(═O)NH—,

L 2 is a substituted or unsubstituted C1 to C10 alkylene group, a substituted or unsubstituted C3 to C20 cycloalkylene group, a substituted or unsubstituted C6 to C20 arylene group, or a substituted or unsubstituted C3 to C20 heterocyclic group,

x is an integer from 0 to 2, and

y is an integer from 0 to 2.

5 . The separator of claim 2 , wherein the sulfonate group-containing unit is represented by Chemical Formula 5, Chemical Formula 6, Chemical Formula 7, or a combination thereof:

wherein, in Chemical Formula 5 to Chemical Formula 7,

R 5 , R 6 , and R 7 are each independently a hydrogen atom or a C1 to C3 alkyl group,

L 3 , L 5 , and L 7 are each independently —C(═O)—, —C(═O)O—, —OC(═O)—, —O—, or —C(═O)NH—,

L 4 , L 6 , and L 8 are each independently a substituted or unsubstituted C1 to C10 alkylene group, a substituted or unsubstituted C3 to C20 cycloalkylene group, a substituted or unsubstituted C6 to C20 arylene group, or a substituted or unsubstituted C3 to C20 heterocyclic group,

a, b, c, d, e, and f are each independently an integer ranging from 0 to 2, and

in Chemical Formula 6, M′ is an alkali metal.

6 . The separator of claim 1 , wherein the polyvinyl alcohol-based polymer comprises polyvinyl alcohol, modified polyvinyl alcohol, or a combination thereof.

7 . The separator of claim 1 , wherein an average thickness of the sheet-shaped inorganic particle is about 10 nm to about 500 nm.

8 . The separator of claim 1 , wherein a specific surface area of the sheet-shaped inorganic particle is about 1 m 2 /g to about 50 m 2 /g.

9 . The separator of claim 1 , wherein the acryl-based copolymer is included in an amount of about 1 wt % to about 30 wt % based on a total weight of the heat resistance layer.

10 . The separator of claim 1 , wherein the polyvinyl alcohol-based polymer is included in an amount of about 0.01 wt % to about 0.03 wt % based on a total weight of the heat resistance layer.

11 . The separator of claim 1 , wherein the sheet-shaped inorganic particle is included in an amount of about 50 wt % to about 99 wt % based on a total weight of the heat resistance layer.

12 . The separator of claim 1 , wherein a thickness of the heat resistance layer is about 0.01 μm to about 20 μm.

13 . A rechargeable lithium battery, comprising:

a positive electrode, a negative electrode, and the separator for a rechargeable battery of claim 1 between the positive electrode and the negative electrode.