Flexible rechargeable Ni//Zn battery based on self-supported NiCo2O4 nanosheets with high power density and good cycling stability

The overall electrochemical performances of Ni-Zn batteries are still far from satisfactory, specifically for rate performance and cycling stability Herein, we demonstrated a high-performance flexible Ni//Zn battery with outstanding durability and high power density based on selfsupported NiCo2O4nanosheets as cathode and Zn nanosheets as anode. This Ni//Zn battery is able to deliver a remarkable capacity of183.1 mAh g-1and a good cycling performance(82.7% capacity retention after 3500 cycles). More importantly, this battery achieves an admirable power density of 49.0 kW kg-1and energy density of 303.8 Wh kg-1, substantially higher than most recently reported batteries. With such excellent electrochemical performance, this battery will have great potential as an ultrafast power source in practical application.