Better engineering layered vanadium oxides for aqueous zinc‐ion batteries: Going beyond widening the interlayer spacing

Abstract

Aqueous zinc‐ion batteries (ZIBs) are regarded as among the most promising candidates for large‐scale grid energy storage, owing to their high safety, low costs, and environmental friendliness. Over the past decade, vanadium oxides, which are exemplified by V2O5, have been widely developed as a class of cathode materials for ZIBs, where the relatively high theoretical capacity and structural stability are among the main considerations. However, there are considerable challenges in the construction of vanadium‐based ZIBs with high capacity, long lifespan, and excellent rate performance. Simple widenings of the interlayer spacing in the layered vanadium oxides by pre‐intercalations appear to have reached their limitations in improving the energy density and other key performance parameters of ZIBs, although various metal ions (Na+, Ca2+, and Al3+) and even organic cations/groups have been explored. Herein, we discuss the advances made more recently, and also the challenges faced by the high‐performance vanadium oxides (V2O5‐based) cathodes, where there are several strategies to improve their electrochemical performance ranging from the new structural designs down to sub‐nano‐scopic/molecular/atomic levels, including cation pre‐intercalation, structural water optimization, and defect engineering, to macroscopic structural modifications. The key principles for an optimal structural design of the V2O5‐based cathode materials for high energy density and fast‐charging aqueous ZIBs are examined, aiming at paving the way for developing energy storage designed for those large scales, high safety, and low‐cost systems.

Hydrated Calcium Vanadate Nanoribbons with a Stable Structure and Fast Ion Diffusion as a Cathode for Quasi-Solid-State Zinc-Ion Batteries

“…Therefore, the electrochemical performance of CaVO-1 is slightly lower than that of the CaVO-2 cathode. Besides, the addition of too much Ca 2+ lead to a reduction in the specific capacity of the material because Ca 2+ had a heavy molar mass and does not provide capacity. , To investigate the cycle lifespan of the battery, long cycle performance tests were conducted at high current densities. As illustrated in Figure f, CaVO-2 exhibited an excellent cycling lifespan at 10 A g –1 .…”

Recent advances in electrospinning nanofiber materials for aqueous zinc ion batteries

“… 85 Usually, vanadium-based materials are semiconductors that possess poor electronic conductivity, so highly conductive substances are often used in the preparation of the cathode electrodes to improve the conductivity of the materials. 86 …”

Enhanced oxygen reduction activity of α-MnO2 by NH3 plasma treatment

“…Currently, humans are facing the challenges of greenhouse effect and rapid energy depletion, and it is urgent to promote the development of sustainable and environmentally friendly energy storage systems [1][2][3][4][5][6][7]. Among various energy storage systems, metal-air fuel cells are known for their high energy density and are considered promising [8][9][10][11].…”