▎ 摘　　要

NOVELTY - Preparation of sodium-vanadium fluorophosphate involves carrying out pre-reaction with vanadium source, phosphorus source and reducing agent in water, adding sodium source and fluorine source to the pre-reaction solution, dispersing to obtain raw material solution, adding alkali solution to the raw material solution, precipitating at 85-95℃ with pH of 5-7, performing solid-liquid separation, washing, and drying. USE - Preparation of sodium-vanadium fluorophosphate used for preparing sodium-vanadium fluorophosphate/carbon composite positive electrode material for sodium-ion battery (all claimed) for electronic device and electric automobile. ADVANTAGE - The method: utilizes water as preparation system, through pre-reaction-precipitation reaction and combined control of temperature and pH of the precipitation stage; provides synergistic synthesis of sodium vanadium fluorophosphate under normal pressure aqueous system, thus effectively improving the yield of the product, improving the crystal grain and surface-active modified structure of product, to improve the electrochemical performance of product in the sodium ion battery, provides simple preparation, low energy consumption, low cost, and environment-friendly, high utilization rate (not less than 90 %), forming fast, sustainable (mother liquor can be reused), suitable for scale production, and utilizes the vanadium source that is low-cost oxide vanadium or metavanadate. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a preparation of a sodium-vanadium fluorophosphate/carbon composite positive electrode active material, which involves compounding the sodium-vanadium fluorophosphate with a carbon source, and carbonizing in a protective atmosphere including nitrogen and/or argon, or adding conductive carbon to the sodium-vanadium fluorophosphate and dispersing. The carbon source is organic substance, preferably starch, β-cyclodextrin and/or glucose. The weight ratio of sodium vanadium fluorophosphate and carbon source is 1:0.05-0.2. The conductive carbon is carbon nanotubes and/or graphene. The weight ratio of sodium vanadium fluorophosphate and conductive carbon is 1:0.005-0.02. DESCRIPTION OF DRAWING(S) - The drawing shows a flow chart illustrating preparation of sodium-vanadium fluorophosphate. (Drawing shows a non-English language text)