Battery assembly employed with separator of sealed top portion and secondary battery comprising the same

Disclosed herein are an electrode assembly having separators the upper ends of which are sealed and a secondary battery including the same. The electrode assembly has a cathode/separator/anode structure that can be charged and discharged. The separators, which protrude beyond the upper ends of the electrodes, are bent in one direction, the separators are heat-treated such that the bent state of the separators is fixed, and an insulative coating layer is formed at the bent surfaces of the separators. Consequently, foreign matter is prevented from being introduced into the electrode assembly, and therefore, the safety of electrode assembly is improved.