Long-lived Aqueous Rechargeable Lithium Batteries Using Mesoporous LiTi2(PO4)3@C Anode

The instability of anode materials during cycling has been greatly limiting the lifetime of aqueous rechargeable lithium batteries (ARLBs). Here, to tackle this issue, mesoporous LiTi2(PO4)3@C composites with a pore size of 4 nm and a large BET surface area of 165 m(2) g(-1) have been synthesized by a novel two-step approach. The ARLB with this type of LiTi2(PO4)3@C anode, commercial LiMn2O4 cathode and 2 M Li2(SO4) aqueous solution (oxygen was removed) exhibited superior cycling stability (a capacity retention of 88.9% after 1200 cycles at 150 mA g(-1) and 82.7% over 5500 cycles at 750 mA g(-1)) and excellent rate capability (discharge capacities of 121, 110, 90, and 80 mAh g(-1) based on the mass of LiTi2(PO4)3 at 30, 150, 1500, and 3000 mA g(-1), respectively). As verified, the mesoporous structure, large surface area and high-quality carbon coating layer of the LiTi2(PO4)3@C composite contribute to the breakthrough in achieving excellent electrochemical properties for ARLB.