A Flexible Rechargeable Zinc–Air Battery with Excellent Low‐Temperature Adaptability

Abstract

Flexible zinc–air batteries (ZAB) are a promising battery candidate for emerging flexible electronic devices, but the catalysis‐based working principle and unique semi‐opened structure pose a severe challenge to their overall performance at cold temperature. Herein, we report the first flexible rechargeable ZAB with excellent low‐temperature adaptability, based on the innovation of an efficient electrocatalyst to offset the electrochemical performance shrinkage caused by decreased temperature and a highly conductive hydrogel with a polarized terminal group to render the anti‐freezing property. The fabricated ZABs show excellent electrochemical performances that outperform those of many aqueous ZABs at room temperature. They also deliver a high capacity of 691 mAh g−1 and an energy density of 798 Wh kg−1 at −20 °C (92.7 % and 87.2 % retention of the room temperature counterparts, respectively), together with excellent flexibility and reverting capability.

Defect Electrocatalysts and Alkaline Electrolyte Membranes in Solid‐State Zinc–Air Batteries: Recent Advances, Challenges, and Future Perspectives

“…In addition, other reaction modifiers have been introduced into the membrane to reduce the charging overpotential by changing the pathway of the conventional OER, which seems to be able to effectively Reproduced with permission. [200] Copyright 2020, Wiley-VCH GmbH.…”

“…[197][198][199] Currently, the popular polymer hosts include poly(ethylene oxide) (PEO), PVA, polyacrylamide (PAM), sodium polyacrylate (PANa), gelatin, and poly(acrylic acid) (PAA), as well as dual-network gels that are based on these polymers. [174,187,[189][190][191][200][201][202] In addition, certain soluble reaction modifiers in the electrolyte could greatly lower the charge voltage of ZABs by introducing an oxidation reaction on the air cathode with lower activation energy barriers. The low charge overpotential minimizing side effects would result in high round-trip efficiency and long-time life.…”

“…In addition, the introduced reaction modifier, I − , changes the pathway of the conventional OER, and significantly reduces the charging overpotential by a thermodynamically favorable pathway. The assembled solid-state ZAB demonstrates an exceptionally low charge voltage of 1.69 V and a long cycling time of 200 h. Besides, some polymer additives such as PEG, PAA, and PANa, [187,189,190,200,201] with excellent water retention capability, show great promise in optimizing PVA-based GPEs. Recently, Hu and co-workers [187] developed a porous PVA-based nanocomposite GPE with high ionic conductivity and electrolyte retention (Figure 17a,b).…”

“…[ 205 ] Recently, Chen al. [ 200 ] synthesized a dual‐crosslinked A‐PAA hydrogel using a free‐radical polymerization method, and the hydrogel electrolyte presented excellent low‐temperature adaptability ( Figure a–c). DFT results suggest that more polarized terminal groups in hydrogels can interact more intensively with the water molecule.…”

Confined Synthesis of N, P Co–Doped 3D Hierarchical Carbons as High‐Efficiency Oxygen Reduction Reaction Catalysts for Zn–Air Battery

“…Nowadays, Pt and its alloys are regarded as state‐of‐the‐art ORR electrocatalysts. Nevertheless, the large‐scale commercialization of the precious catalysts is limited by the high‐cost and poor stability of Pt . Therefore, great efforts are devoted to develop inexpensive, durable, and high‐performance ORR catalysts.…”