Large Scalable Preparation of Ti -Doped Na4fe3(Po4)2p2o7 as Cathode Material for High Rate and Long-Life Sodium Ion Batteries

Sodium-ion batteries (SIBs) have received widespread attention in the domain of large-scale energy storage on account of its cost advantages. With regard to electrode materials applied in the energy-storage field, low cost, long life and scalable synthesis are first to be considered. However, there are no reports of such materials for mass production. Herein, using FePO4 and Na2CO3 as source materials, a green and scalable synthesis method has been developed to synthesis Na4Fe3(PO4)2P2O7/C (NFPP/C) composite. In addition, the Ti-doping strategy is adopted to remedy its poor electrical conductivity, which will improve its discharge capacity and cycle stability. The prepared Ti-Na4Fe3(PO4)2P2O7/C (Ti-NFPP/C) cathode exhibits excellent rate performances (66.7 mAh g−1 at 30 C) and cycling stability (capacity retention of 93.8 % after 2000 cycles at 10 C). In particular, the Ti-Na4Fe3(PO4)2P2O7/C//HC full battery assembled by the Ti-NFPP/C cathode and hard carbon (HC) anode exhibits an energy density of 145 Wh kg−1 at 0.5 C. The results provide a feasible approach for sodium-ion batteries to be applied in business.