Solution-Processed All-V2 O5 Battery.

Exploring new battery technologies will promote the advance of energy storage systems. Designing a symmetrical-structured rechargeable battery with the same electrode materials is a meaningful exploration for battery technology. Here, a solution-processed all-V2 O5 rechargeable battery with V2 O5 as both anode and cathode is presented, in which the anionic/cationic redox reactions are decoupled by precisely clamping its working potential windows. The battery shows good electrochemical performance with high capacity of 151 mAh g-1 at 0.10 C, good rate performance with 70% capacity retention when the current increases from 0.10 to 5 C, and promising cycling stability over 83% capacity retention after 900 cycles at 1 C. Moreover, the battery is highly profitable for simplified fabrication and scalable production, which benefits from its symmetrical configuration as well as the solution-processed strategy. This work offers a new paradigm to construct advanced symmetrical energy storage devices.