| abstract |
The present invention relates to: a composite separation membrane for a lithium secondary battery, having an excellent effect of improving the lifetime and safety of a battery; and a lithium secondary battery comprising the same and, more specifically, to a composite separation membrane comprising: a porous base layer; a heat-resistant layer formed on one side or both sides of the porous base layer; and a fusion layer formed on an outermost layer, wherein the heat-resistant layer includes inorganic particles connected and fixed by binder polymers, and the fusion layer includes crystalline polymers in the form of particles having a melting temperature of 100°C or higher. |