High-performance LiTi2(PO4)3 anodes for high-areal-capacity flexible aqueous lithium-ion batteries
Developing flexible, high-energy and low-cost rechargeable batteries is critical to fulfil the increasing demands of flexible electronic devices. In this work, we report a high-performance nitrogen-doped carbon-coated LiTi2(PO4)3 (N-ccLTP) prepared via a one-pot carbonization incorporating sol–gel method. The N-ccLTP anode demonstrates an excellent rate capability with a superior cycle life up to 1000–2000 cycles at high C-rates (5C and 10C). Using the N-ccLTP anode coupled to a LiMn2O4 cathode, we develop high-areal-capacity flexible aqueous lithium-ion batteries (ALIBs). Under a wide range of bending curvatures at continuous and cyclic bending modes, the flexible ALIBs show no degradation from the non-bending state and demonstrated superior stability with a high areal capacity of 1.2–1.4 mA h cm−2 and a high volumetric energy density of 26–31 mW h cm−3. The designs of the N-ccLTP anode material and the flexible device structure offer effective strategies to develop high-performance flexible ALIBs for flexible electronic applications.