Disclosed is an electrolyte for a battery, which comprises: (a) an electrolyte salt; (b) a solvent for electrolyte; and (c) a compound represented by the following formula 1: wherein R is a halogen atom, or a halogen-substituted or non-substituted C1˜C10 alkyl group or alkenyl group. An electrode comprising a passivation layer partially or totally formed on a surface thereof, wherein the passivation layer comprises a compound represented by the following Formula 1 or a chemical reaction product thereof, and a secondary battery using the electrolyte and/or the electrode are also disclosed. The compound can improve the initial charge/discharge efficiency and cycle life characteristics of a secondary battery, and can inhibit a battery from swelling under high-temperature storage conditions.