Rechargeable alkaline zinc batteries: Progress and challenges

2020 Roadmap on Zinc Metal Batteries

“…For Zn anode, H 2 evolution corrosion and Zn dendrite issues also deteriorate the electrochemical performance and safety of ZnÀ Ag batteries. [7] In addition, silver oxide can be dissolved in alkaline electrolytes during charge/discharge process, leading to the formation of Ag(OH) 2 À species, which will oxidize separators and cause the decomposition of separators. Meanwhile, Ag(OH) 2 À also will be reduced to Ag particles on separators resulting in the short circuit of battery.…”

“…Therefore, improving the stability of AgO cathode and inhibiting O 2 evolution play vital roles in guaranteeing long cycle stability and reserve life of Zn−Ag batteries with high energy and power density. For Zn anode, H 2 evolution corrosion and Zn dendrite issues also deteriorate the electrochemical performance and safety of Zn−Ag batteries [7] . In addition, silver oxide can be dissolved in alkaline electrolytes during charge/discharge process, leading to the formation of Ag(OH) 2 − species, which will oxidize separators and cause the decomposition of separators.…”

A Function‐Separated Design of Electrode for Realizing High‐Performance Hybrid Zinc Battery

“…Alkaline Zn–transition metal compound (Zn–MX) batteries (e.g., Zn–Co batteries, Zn–Ni batteries) are important categories of Zn‐based batteries. [ 11 ] Some of the cathode materials (Co 3 O 4 , [ 12 ] NiO [ 13 ] ) for the Zn–MX batteries demonstrated higher discharge voltages than the conventional air cathodes for Zn–air batteries. By introducing the function of a Zn–MX battery into the air electrode of a Zn–air battery, a so‐called hybrid Zn battery was proposed, which may show both high power density and excellent energy density.…”

“…The construction of a porous electrode with suitable pore size and pore distribution is a widely adopted strategy in Zn–air batteries and Zn–MX batteries, which can improve the mass transfer to some extent. [ 11,33–36 ] Another effective strategy for achieving fast mass transfer is through tuning the wettability (i.e., hydrophilicity or hydrophobicity) of the cathode. [ 30,37,38 ] The Faradaic cation redox in a Zn–MX battery cathode requires improved electrolyte accessibility for better ionic transfer, [ 11 ] while the oxygen redox in a Zn–air battery cathode requires improved gas accessibility for accelerated gas diffusion.…”

“…[ 11,33–36 ] Another effective strategy for achieving fast mass transfer is through tuning the wettability (i.e., hydrophilicity or hydrophobicity) of the cathode. [ 30,37,38 ] The Faradaic cation redox in a Zn–MX battery cathode requires improved electrolyte accessibility for better ionic transfer, [ 11 ] while the oxygen redox in a Zn–air battery cathode requires improved gas accessibility for accelerated gas diffusion. [ 39 ] The conventional single‐layer electrode design, however, can only meet one of the two requirements, i.e., establishing either a hydrophilic interface for facilitating ionic transfer or a hydrophobic interface for providing better gas diffusion.…”