Composition for electrolyte of lithium secondary battery, gel polymer electrolyte, and lithium secondary battery including gel polymer electrolyte

A composition for an electrolyte of a lithium secondary battery, comprising:

• a lithium salt;
• an organic solvent;
• a polyalkylene carbonate-based first polymer having a weight average molecular weight of 1,000 g/mol to 1,500,000 g/mol, wherein an amount of the first polymer is in a range of 0.1 wt % to 30 wt % based on a total weight of the composition;
• and
• a polypropylene carbonate-based second polymer including a unit represented by Formula 2 and having a weight average molecular weight of 200 g/mol to 1,000 g/mol, wherein the weight average molecular weight of the second polymer is in a range of 1/3,000 to ⅓ of the weight average molecular weight of the first polymer:
• wherein in the Formula 2,
• R5 to R8 are the same as or different from each other and are each independently hydrogen, or an alkyl group having 1 to 5 carbon atoms, and at least one of R5 to R8 is an alkyl group having 1 to 5 carbon atoms,
• * is a site connected to a main chain or an end group of the second polymer, and
• h is a number of the unit represented by the Formula 2 and an integer of any one of 1 to 200.