▎ 摘　　要

NOVELTY - Preparing carbon-wrapped pyrophosphate polyanion composite material, comprises dispersing sodium source, iron source, phosphorus source, doping element source, carbon source and reducing agent in a solvent, high-energy ball milling, drying, tableting and sintering. The mol ratio of sodium element, iron element and phosphorus element in the raw material is 3-3.3:1.8-2.5:3.9-4.1. The mol ratio of metal element and reducing agent in the raw material is 2-3:3. The conditions of the sintering process are: the temperature is 400-600°C under an inert/reducing atmosphere, and the time is 6-20 hours. The mol ratio of described sodium element and doping element is 3-3.3:0-0.5. The doping element is manganese, vanadium, titanium, magnesium, aluminum, copper, yttrium or zirconium. USE - The material is useful as anode active material for sodium ion battery (claimed). ADVANTAGE - The material has high voltage platform, good stability, and excellent electrochemical performance. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for carbon-wrapped pyrophosphate polyanion composite material.