▎ 摘　　要

NOVELTY - Preparation of linear aqueous lithium ion battery comprises preparing polyimide/graphene composite fiber through hydrothermal reaction; preparing lithium iron phosphate/graphene composite fiber through hydrothermal reaction; preparing aqueous gel electrolyte using lithium sulfate as main raw material; and assembling polyimide/graphene composite fiber as negative electrode, lithium iron phosphate/graphene composite fiber as positive electrode and lithium sulfate gel electrolyte as electrolyte. USE - Method for preparation of linear aqueous lithium ion battery (claimed). ADVANTAGE - The linear lithium ion battery saves 90% of the initial capacity at 20C current charge and discharge of 200 times, and has energy density and power density close to the conventional lithium ion battery, battery power density of 10000 W/kg and energy density of 50 W.hour/kg, and Coulomb efficiency close to 100%.