A review on system and materials for aqueous flexible metal–air batteries

Abstract

The exploration of aqueous flexible metal–air batteries with high energy density and durability has attracted many research efforts with the demand for portable and wearable electronic devices. Aqueous flexible metal–air batteries feature Earth‐abundant materials, environmental friendliness, and operational safety. Each part of one metal–air battery can significantly affect the overall performance. This review starts with the fundamental working principles and the basic battery configurations and then highlights on the common issues and the recent advances in designing high‐performance metal electrodes, solid‐state electrolytes, and air electrodes. Bifunctional oxygen electrocatalysts with high activity and long‐term stability for constructing efficient air electrodes in flexible metal–air batteries are summarized including metal‐free carbon‐based materials and nonprecious Co/Fe‐based materials (alloys, metal oxides, metal sulfites, metal phosphates, metal nitrates, single‐site metal–nitrogen–carbon materials, and composites). Finally, a perspective is provided on the existing challenges and possible future research directions in optimizing the performance and lifetime of the flexible aqueous solid‐state metal–air batteries.

Multiple‐dimensioned defect engineering for graphite felt electrode of vanadium redox flow battery

“…At present, enormous attention has been attributed to renewable energy technologies due to the overuse of fossil fuels resulting in irreversible environmental pollution and an energy depletion crisis. It is a key way to get out of the energy predicament by developing solar, wind, and tidal energy by virtue of their cleanness and renewability 1–5 . However, there is a problem in realizing effective usage of new energy owing to uncontrollable intermittency.…”

Impact of aluminum alloy grade as anode on electrochemical performance for Al‐Air cell in alkaline electrolyte

“…Each has some pros and cons, simultaneously 12‐15 . Among them, zinc anode‐based air batteries are explored widely due to their electrochemical rechargeable nature, high working potential~1.66 V, and currently being used in portable and wearable systems like hearing aids, and so forth 16 . Fe‐air batteries are also rechargeable and cost‐effective as well, but the low energy density is not meeting the expectations.…”

“…[12][13][14][15] Among them, zinc anode-based air batteries are explored widely due to their electrochemical rechargeable nature, high working potential$1.66 V, and currently being used in portable and wearable systems like hearing aids, and so forth. 16 Fe-air batteries are also rechargeable and costeffective as well, but the low energy density is not meeting the expectations. Deyab et al 17 have used ionic liquid for Fe-air battery to enhance their performance and obtained 416 mAh g À1 capacity with 94% retention after 1000 cycles.…”

Dysprosium-induced FeNx-Dy2O3 sites for Efficient Bifunctional Oxygen Electrocatalytic Reactions

“…With the worsening of global energy crisis and environmental pollution, it is urgent to develop clean, sustainable and high energy density energy storage and conversion devices such as fuel cells and metalair batteries [1][2][3][4][5][6] . Compared with traditional lithium batteries, rechargeable Zn-air batteries with abundant Zn resources, large speci c capacity, low cost and no explosion have great potential in the eld of new energy storage and conversion [7][8][9][10] .…”