Hierarchical Porous Bi2Te3@C for Wide-Temperature-Range Aqueous Zn-Based Batteries with Air-Recharging Capability

Air-rechargeable batteries integrating energy harvesting, conversion, and storage provide the most portable and popular approach to self-charging power systems. However, air-rechargeable batteries are currently mostly aqueous Zn-based battery systems in which it has remained a significant challenge to solve the low discharge capacities and poor cycling stability of chemical self-charging due to continuous insertion/extraction of large-size hydrated Zn2+. Herein, efficient Bi2Te3@C cathodes with an active carbon paper substrate are developed. Further ex situ characterization analysis confirms the energy storage mechanism regarding the coexistence of H+/Zn2+ coinsertion and conversion reaction in the aqueous Zn||Bi2Te3@C battery. Benefiting from the fast dynamics process attributed to the unique mechanism, a reliable energy supply is provided even in an extended temperature range from −10 to 45 °C. More importantly, Bi2Te3@C cathodes boost the superior and repeatable air-rechargeability. A discharge capacity of up to 264.20 mA h g–1 at 0.30 A g–1 is manifested after self-charging for 11.00 h. In addition, two quasi-solid-state battery devices are connected in series to continuously power a timer. After the device is discharged and then air self-charged for just a few seconds, an LED is lit.