Synthesis and characterization of binary and ternary phases in the Li–Si–P system as new materials for Li-ion batteries

The binary compounds Li15Si4 and SiP were synthesized via various synthetic methods, structurally and morphologically characterized and tested against lithium as anode materials. The reactivity of Li15Si4 with the electrolyte was investigated. The investigation of the ternary Li–Si–P system led to the discovery of four new compounds: Li8SiP4, Li5SiP3, Li2SiP2 and Li10.68(3)Si5P. The new phases were structurally characterized via X-ray diffraction and solid-state NMR spectroscopy. The Li-ion conductivity of Li8SiP4 and Li2SiP2 was determined by impedance spectroscopy.