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 MnO 2 @carbon nanotube fiberlike composite cathode and Zn wire anode. The Zn–MnO 2 cable microbattery exhibits a large specific capacity, good rate performance, and cyclic stability. The capacity of Zn–MnO 2 cable batteries are 322 and 290 mAh/g based on MnO 2 with aqueous and gel polymer electrolyte, corresponding to the specific energy of 437 and 360 Wh/kg, respectively. Besides, the Zn–MnO 2 cable battery shows excellent flexibility, which can be folded into arbitrary shapes without sacrificing electrochemical performance. Furthermore, we studied electrochemical properties of Zn–MnO 2 cable microbatteries with different Zn salt electrolytes, such as Zn salt with small anions (ZnSO 4 or ZnCl 2, etc.) and Zn salt with bulky anions (Zn(CF 3 SO 3 ) 2, etc.). With the merits of impressive electrochemical performance and flexibility, this first flexible rechargeable Zn–MnO 2 cable-like battery presents a new approach to develop high-performance power sources for portable and wearable electronics.