▎ 摘　　要

NOVELTY - Preparation of graphene coated spherical cobalt sulfide composite material comprises dissolving 0.2-0.5 g cobalt acetate tetrahydrate in 5-15 mL deionized water, adding to 25 mL alumina graphene solution, stirring for 10 minutes, adding 0.3-0.6 g L-cysteine, stirring, adding 10 mL ethylene glycol, stirring, heating at 120-180 degrees C, reacting for 6-18 hours, washing with deionized water, and drying. USE - Method for preparing graphene-coated spherical cobalt sulfide composite material used for sodium-ion battery (all claimed). ADVANTAGE - The method is simple, stable, inexpensive, repeatable, and has high product capacity. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for the preparation of sodium-ion battery comprising mixing cobalt sulfide, polyvinylidene fluoride and acetylene black at mass ratio of 70:20:10, grinding, coating on copper cathode, using sodium metal as counter electrode, and adding electrolyte.