High-Performance Cable-Type Flexible Rechargeable Zn Battery Based on MnO2@CNT Fiber Microelectrode

Nowadays, linear-shaped batteries have received increasing attentions because the unique one-dimensional architecture offers an omni-directional flexibility. We developed a cable-type flexible rechargeable Zn microbattery based on a microscale MnO2@carbon nanotube fiberlike composite cathode and Zn wire anode. The Zn-MnO2 cable microbattery exhibits a large specific capacity, good rate performance, and cyclic stability. The capacity of Zn-MnO2 cable batteries are 322 and 290 mAh/g based on MnO2 with aqueous and gel polymer electrolyte, corresponding to the specific energy of 437 and 360 Wh/kg, respectively. Besides, the Zn-MnO2 cable battery shows excellent flexibility, which can be folded into arbitrary shapes without sacrificing electrochemical performance. Furthermore, we studied electrochemical properties of Zn-MnO2 cable microbatteries with different Zn salt electrolytes, such as Zn salt with small anions (ZnSO4 or ZnCl2, etc.) and Zn salt with bulky anions (Zn(CF3SO3)(2), etc.). With the merits of impressive electrochemical performance and flexibility, this first flexible rechargeable Zn-MnO2 cable-like battery presents a new approach to develop high-performance power sources for portable and wearable electronics.