Disclosed is a binder, which comprises polymer particles obtained by polymerization of: (a) 1˜80 parts by weight of a (meth)acrylic acid ester monomer; (b) 1˜20 parts by weight of an unsaturated carboxylic acid monomer; and (c) 0.001˜40 parts by weight of a vinyl monomer, based on 100 parts by weight of the binder polymer, and which allows electrode active material particles capable of lithium intercalation/deintercalation to be fixed and linked among themselves, and between the particles and a collector. An electrode comprising the binder, and a lithium secondary battery having the electrode are also disclosed. Further, a method for evaluating interrelation between wettability of a binder to an electrolyte and quality of a battery comprising the binder is disclosed.