An efficient dual-phase strategy of preparing K_0.5V₂O₅/NaV₃O₈ hybrid for durable zinc storage

Rechargeable aqueous zinc-ion batteries (ZIBs) are promising candidates in energy storage because of intrinsic safety, low-cost and eco-friendliness. However, restricted by cathode materials, ZIBs usually exhibit inferior capacity and limited cycling performance. Herein, an efficient dual-phase strategy is employed to fabricate novel heterogeneous K0.5V2O5/NaV3O8 (KNaVO) hybrid cathode. In traditional aqueous batteries, the hybrid persistently offers long lifespan zinc-ions storage with reversible capacity of 150 mAh g(-1) up to 5500 at 5 A g(-1), and impressive rate performance with 128.7 mAh g(-1) even at 10 A g(-1) due to the ameliorated conductivity and conspicuous pseudocapacitance effect. In quasi-solid-state batteries, the flexible ZIBs can well withstand large-angle deformation from 30 degrees to 120 degrees. And at a large bend angle, ZIBs harvest the considerable capacity of 138.4 mAh g(-1) after 1050 cycles at 1 A g(-1) due to robust mechanical strength of gel electrolyte and enhanced Zn-storage of dual-phase structured KNaVO. This will be a prospect of applying flexible quasi-solid-state ZIBs in portable and wearable electronics.