Abstract: The present invention provides a composition for a gel polymer electrolyte, including an oligomer represented by Formula 1; a polymerization initiator; a non-aqueous solvent; and a lithium salt, and a gel polymer electrolyte and a lithium secondary battery including the same.

Abstract: The present invention relates to a method for preparing a lithium bis(fluorosulfonyl)imide salt, including a step of dissolving bis(chlorosulfonyl)imide in an organic solvent in a non-glass vessel to prepare a first reaction solution; a step of injecting lithium fluoride (LiF) to the first reaction solution in the non-glass vessel and refluxing while heating to prepare a second reaction solution; a step of separating a product including a lithium bis(fluorosulfonyl)imide salt and the organic solvent from the second reaction solution; and a step of obtaining the lithium bis(fluorosulfonyl)imide salt in a solid phase from the product, wherein the organic solvent is at least one or more selected from the group consisting of ethyl acetate, butyl acetate, chloroform, dichloromethane, dichloroethane, benzene, xylene and acetonitrile.

Abstract: The present invention provides a method for manufacturing a lithium secondary battery, the method including injecting a composition for a gel polymer electrolyte into a lithium secondary battery case having an electrode assembly including a metal electrode current collector and then sealing the same, placing the lithium secondary battery case inside a fixing member having an electromagnetic field generation means, and heating the metal electrode current collector using the electromagnetic field generation means, to heat-cure the composition for a gel polymer electrolyte.

Abstract: A lithium secondary battery is disclosed herein. In some embodiment, a lithium secondary battery which includes a positive electrode including a positive electrode material mixture layer, wherein the positive electrode material mixture layer has a loading capacity of 3.7 mAh/cm2 to 10 mAh/cm2, a negative electrode including a negative electrode material mixture layer, a separator disposed between the positive electrode and the negative electrode, and a non-aqueous electrolyte solution including a lithium salt, an organic solvent, and a compound represented by Formula 1, the concentration of the lithium salt in the non-aqueous electrolyte solution is 1.5 M to 3 M, the organic solvent is a mixed solvent including a cyclic carbonate-based organic solvent and a linear carbonate-based organic solvent, and the compound represented by Formula 1 is included in an amount of 0.1 wt % to 5 wt % based on a total weight of the non-aqueous electrolyte solution.

Abstract: The present invention relates to an electrolyte for a lithium secondary battery and a lithium secondary battery including the same, the electrolyte including a lithium salt, an additive containing a compound represented by Formula 1, and an organic solvent.

Abstract: An electrolyte for a lithium secondary battery, and a lithium secondary battery including the same are disclosed herein. In some embodiments, an electrolyte includes a lithium salt having a concentration of 1.6 M to 5 M, an oligomer including a unit represented by Formula A, and an organic solvent including a cyclic carbonate-based compound and an acetate-based compound, wherein the cyclic carbonate-based compound is present in an amount of 6 vol % to 19 vol % based on the total volume of the organic solvent.

Abstract: The present invention provides a lithium secondary battery comprising a non-aqueous liquid electrolyte comprising lithium bis(fluorosulfonyl)imide (LiFSI) and a fluorinated benzene-based compound as additives, a positive electrode comprising a lithium-nickel-manganese-cobalt-based oxide as a positive electrode active material, a negative electrode, and a separator. With the non-aqueous liquid electrolyte for a lithium secondary battery of the present invention, a solid SEI film is formed on a negative electrode when initially charging a lithium secondary battery comprising the non-aqueous liquid electrolyte, and an output property of the lithium secondary battery is improved, and an output property and stability after high temperature storage are capable of being enhanced as well.

Abstract: The present invention relates to a method of preparing a pouch type secondary battery, and particularly to a method of preparing a pouch type secondary battery which includes preparing a pouch type preliminary secondary battery by accommodating an electrode assembly in an inner space of a pouch type case, disposing a metallic ultrasonic member by being closely attached to both surfaces of the pouch type preliminary secondary battery, injecting a composition for a gel polymer electrolyte into the pouch type preliminary secondary battery, applying ultrasonic vibration to the pouch type preliminary secondary battery while pressurizing the pouch type preliminary secondary battery using the ultrasonic member, performing formation on the pouch type preliminary secondary battery, curing the composition for a gel polymer electrolyte, and degassing, wherein the ultrasonic member is maintained at a temperature of 30° C. to 80° C.

Abstract: An electrolyte additive composition of the present invention may improve high-rate charge and discharge characteristics and high-temperature storage and life characteristics of a lithium secondary battery when the electrolyte additive composition is used in an electrolyte while including a novel borate-based lithium compound as well as a non-lithiated additive.

Abstract: An electrolyte for a lithium secondary battery and a lithium secondary battery including the same are disclosed herein. In an embodiment, an electrolyte for a lithium secondary battery includes a lithium salt, an organic solvent, and an oligomer represented by Formula 1 described in the present specification or a polymer derived from the oligomer represented by Formula 1. A lithium secondary battery including the electrolyte for a lithium secondary battery is improved by suppressing reactivity of lithium metal.