Separator for lithium secondary battery and lithium secondary battery comprising same

A separator for a lithium secondary battery, comprising:

• a porous polymer substrate;
• and
• a porous coating layer on at least one surface of the porous polymer substrate,
• wherein the porous coating layer comprises flame-resistant particles, a heat resistant binder polymer and a fluorine-containing binder polymer,
• wherein the flame-resistant particles have an endothermic reaction temperature at 150° C. to 250° C.,
• wherein the heat resistant binder polymer have a K-value of 120 or more and a glass transition temperature of 100° C. or higher,
• wherein a weight ratio, R, of the flame-resistant particles to the heat resistant binder polymer satisfies Formula 1, and
• wherein an amount of the fluorine-containing binder polymer is larger than an amount of the heat resistant binder polymer:
• 5<R≤10. [Formula 1]