Advanced Fiber-Shaped Aqueous Zn Ion Battery Integrated with Strain Sensor
Haozhe Zhang, Ting Xiong, Tianzhu Zhou, Xiao Zhang, Yuntian Wang, Xuhui Zhou, Lei Wei
Abstract
Multifunctional batteries have attracted increasing attention, offering additional functionalities beyond the conventional batteries. Herein, we report a fiber-shaped Zn ion battery that not only acts as a high-performance power supply but also provides a sensing function to monitor human motions. Titanium fiber coated with α-MnO2 nanoflowers is exploited as the cathode for the fiber-shaped Zn ion battery, taking full advantage of such unique three-dimensional nanoflower structures of α-MnO2 with a large electrochemically active surface area and fast electrochemical reaction kinetics. Thus, the obtained fiber-shaped Zn ion battery shows a high capacity of 280 mAh g–1 at 0.1 A g–1, resulting in a notable energy density of 396 Wh kg–1, good stability (capacity retention of 80.6% after 300 cycles), and high flexibility. As a demonstration, an electronic watch and five LEDs are successfully driven by two fiber-shaped Zn ion batteries. Furthermore, the fiber-shaped Zn ion battery is integrated with a strain sensor based on a carbon nanotube/polydimethylsiloxane film, offering good sensitivity to monitor motions of different body parts, such as the wrist, finger, elbow, and knee. This work provides insights into multifunctional battery applications for next-generation wearable electronics.