Abstract: An electrolyte for a lithium secondary battery is provided. The electrolyte improves battery safety, high temperature storage characteristics, and electrochemical properties of lithium batteries. The electrolyte comprises at least one lithium salt and a non-aqueous organic solvent comprising a cyclic carbonate and a lactone-based compound. The lactone based compound comprises substituents selected from the group consisting of alkyl groups, alkenyl groups, alkynyl groups, aryl groups, and combinations thereof. A lithium battery is also provided, which comprises a negative electrode capable of intercalating/deintercalating lithium, a positive electrode capable of intercalating/deintercalating lithium, and an inventive electrolyte.

Abstract: A polymer electrolyte composition for a rechargeable lithium battery includes an acrylate-based polymer, a lactone-based compound having an alkyl substituent, a non-aqueous organic solvent, and a lithium salt. The electrolyte for a rechargeable lithium battery of the present invention exhibits excellent high temperature storage characteristics, excellent high temperature cycle-life characteristics, and improved safety without deteriorating cell performance.

Abstract: The present embodiments relate to a method and an apparatus for managing fuel cell performance and a direct methanol type fuel cell using the method, capable of setting an activation time point to a user's use time point and spontaneously performing performance recovery during long time use thereof. The method for managing performance of the fuel cell stack according to the present embodiments includes the steps of: receiving a first drive request signal or a performance recovery request signal; circulating high-concentration liquid fuel having higher density than fuel supplied to a stack through an anode flow of the fuel cell stack in response to the received request signal; and circulating water through the anode flow after stopping the circulation of the high-concentration liquid fuel.

Abstract: A polymer electrolyte composition for a rechargeable lithium battery includes an acrylate-based polymer, a lactone-based compound having an alkyl substituent, a non-aqueous organic solvent, and a lithium salt. The electrolyte for a rechargeable lithium battery of the present invention exhibits excellent high temperature storage characteristics, excellent high temperature cycle-life characteristics, and improved safety without deteriorating cell performance.

Abstract: An electrolyte for a lithium secondary battery is provided. The electrolyte improves battery safety, high temperature storage characteristics, and electrochemical properties of lithium batteries. The electrolyte comprises at least one lithium salt and a non-aqueous organic solvent comprising a cyclic carbonate and a lactone-based compound. The lactone based compound comprises substituents selected from the group consisting of alkyl groups, alkenyl groups, alkynyl groups, aryl groups, and combinations thereof. A lithium battery is also provided, which comprises a negative electrode capable of intercalating/deintercalating lithium, a positive electrode capable of intercalating/deintercalating lithium, and an inventive electrolyte.