Confining ultrafine Li3P nanoclusters in porous carbon for high-performance lithium-ion battery anode

High-capacity lithium-containing alloy anodes (e.g., Li4.4Si, Li4.4Sn, and Li3P) enable lithium-free cathodes (e.g., Sulfur, V2O5, and FeF3) to produce next-generation lithium-ion batteries (LIBs) with high energy density. Herein, we design a Li3P/C nanocomposite with Li3P ultrafine nanodomains embedded in micrometer-scale porous carbon particles. Benefiting from the unique micro/nanostructure of the Li3P/C nanocomposite, electrons transfer rapidly through the conductive pathway provided by the porous carbon framework and the volume change between Li3P and P is confined in the nanopores of the carbon, which avoids the collapse of the whole Li3P/C composite particles. As expected, the as-achieved Li3P/C nanocomposite provided a high available lithium-ion capacity of 791 mAh/g (calculated based on the mass of Li3P/C) at 0.1 C during the initial delithiation process. Meanwhile, the Li3P/C nanocomposite showed 75% of its 0.5 C capacity at 6 C and stable cycling stability.