Epoxy resin-derived N, P co-doping hard carbon with improved yield and anode performance in Li-ion battery

Electrochemical energy storage devices play key roles in collecting energy from new energy power sources, transferring energy in place and time difference, and supplying energy for those energy consumers. In this work, in order to further improve the high energy density of Li-ion battery, a hard carbon anode is suggested by chosen epoxy as carbon source, accompanied by the simultaneous introduction of three curing agents (dicyandiamide, phytic acid (PA), and ferric acetylacetone). Furthermore, dicyandiamide supplies N-dopant, while PA gives P-dopant and also increases the yield of hard carbon from 23.6 to 40.9%. Based on the synergistic effect of N and P atoms, as well as catalytic effect of Fe, the optimized hard carbon of CNFP-60–700, as Li-ion battery anode, exhibits a reversible capacity of 779.2 mAh g −1 and an initial Coulombic efficiency (ICE) of 58.8% at 0.1 A g −1 for the first cycle, and it still retains a capacity of 508.3 mAh g −1 after 160 cycles.