AlSixP: A new family of ternary Si-based anodes for Li-ion batteries with superior Li-storage properties

Silicon, as the highest capacity lithium-ion battery (LIB) anode material, has been commercialized due to its mature industrial foundation, abundant reserves, and environmental benign. However, its relatively slow Li-ionic and electronic conductivity impede its large-scale application when fast charging and discharging are required. To significantly improve the reaction kinetics, we propose to co-introduce aluminum and phosphorus into silicon at the same time, forming a novel family AlSixP (x = 1, 3, 6) solid solutions. As anodes for LIBs, the equimolar compound of AlSiP presents longer cycling stability and much higher rate performance than Si counterparts due to the faster electronic and Li-ionic conductivity and the rich underlithiated electrochemical intermediates of which reduce the volume variation. The AlSi3P and AlSi6P are also prepared and present similar Li-storage superiority, suggesting the AlSixP series materials are promising to be utilized in the real world.