▎ 摘　　要

NOVELTY - Aqueous calcium-ion battery anode active material comprises nano- wire or nano- strip-shaped potassium vanadate. The potassium vanadate is K2V6O16.nH2O, where 0less than or equal tonless than or equal to2.7. USE - The aqueous calcium-ion battery anode active material is useful as composition of the calcium ion battery anode material in the calcium ion battery (claimed). ADVANTAGE - The anode active material: has excellent electrochemical performance and cycle performance; and exhibits a higher specific capacity. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for preparing the aqueous calcium-ion battery anode active material comprising (i) adding ammonium meta vanadate into deionized water, stirring until the ammonium meta vanadate is completely dissolved to obtain a light yellow solution, then adding potassium chloride and continuously stirring until the potassium meta vanadate is completely dissolved to obtain a mixed solution, adjusting the pH value of the mixed solution obtained in the resultant step to 2-4, then transferring the mixed solution to a reaction kettle for hydrothermal reaction, and naturally cooling the mixed solution to room temperature after the reaction is finished obtaining a brownish green product, and (iii) centrifugally washing the resultant brown green product and then freeze-drying to obtain the product.