High-performance silicon-aluminum composite negative electrode material, preparation method and application thereof

Abstract

This invention relates to a high-performance silicon-aluminum composite anode material, its preparation method, and its application. The high-performance silicon-aluminum composite anode material comprises: an aluminum-containing compound, and nano-silicon particles uniformly attached to a framework structure formed by the aluminum-containing compound; the aluminum-containing compound comprises: aluminum powder and / or lithium-aluminum alloy; the average particle size D of the aluminum-containing compound is... 50 The nanoparticles are between 5μm and 60μm; the proportion of nano-silicon particles in the high-performance silicon-aluminum composite anode material is 40wt% to 90wt%, and the proportion of aluminum-containing compounds is 10wt% to 60wt%; the high-performance silicon-aluminum composite anode material is obtained by ball milling nano-silicon particles and aluminum-containing compounds at low speed; the anode sheet prepared by the high-performance silicon-aluminum composite anode material of the present invention has the advantages of high electrode mechanical stability and fast electrode kinetics. When the anode sheet is assembled into a lithium-ion battery, the specific capacity, energy density, first-cycle coulombic efficiency and cycle performance of the battery can be improved.

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