▎ 摘　　要

NOVELTY - Graphene nanosheet comprises an alkaline chloride layer formed on its surface. USE - The nanosheet is useful in cathode active material for lithium secondary battery (all claimed). ADVANTAGE - The sheet improves initial efficiency of battery. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for producing graphene nanosheet, comprising (a) preparing graphene nanosheet, (b) mixing and stirring an aqueous solution of alkali chloride and graphene nanosheet, (c) filtering out the stirred mixture under reduced pressure, and (d) drying the obtained product in a vacuum oven at 60-200 degrees C.