The invention discloses carbon-coated
doping modified
lithium titanate and a preparation method thereof. The carbon-coated
doping modified
lithium titanate is characterized in that carbon-coated
doping modified
lithium titanate has a general formula of Li[4-x]MgxTi[5-y]AlyO12 / C, wherein x is not less than 0.05 and not greater than 0.5, and y is not less than 0.02 and not greater than 0.25. The preparation method sequentially comprises the following steps of: dispersing
titanium dioxide, soluble
sugar and
aluminium powder or
iron powder in absolute ethyl
alcohol, stirring to obtain a suspension,
drying to obtain a paste, performing heat treatment to obtain carbon-coated
titanium dioxide, soaking with
hydrochloric acid or sulphuric acid, and preparing carbon-coated
titanium dioxide with micro pores on a
coating layer via washing,
drying and
grinding; weighing a lithium source, carbon-coated
titanium dioxide, a
magnesium source and an
aluminium source, and mixing; calcining the
mixed materials, and preserving heat; and
grinding and sieving to obtain the carbon-coated doping modified
lithium titanate. The carbon-coated doping modified
lithium titanate and the preparation method thereof disclosed by the invention have the greatest
advantage that the
conductivity of the material is remarkably improved and a high
discharge specific capacity and an excellent
cycling stability are shown under a
high rate. The method is simple in process, low in
raw material price and available in raw materials, and easily realizes industrialized production. The carbon-coated doping modified
lithium titanate and the preparation method thereof have a wide application prospect in the fields of negative materials for small, power and energy-storing lithium
ion batteries.