We fabricated rechargeable iron ion batteries (RIIBs) using mild steel (MS) as a negative electrode, vanadium penta oxide as a positive electrode, and ferrous perchlorate hydrate in tetra-ethylene glycol dimethyl ether (TGDME)-based solvent under ambient conditions without any inert atmosphere and investigated the performance degradation. The cell exhibits ~ 120 mAh g⁻¹ specific capacity at a 33 mAg⁻¹ current density. The initial capacity fades to about 41% in 30 cycles. The cell was disassembled, and post-mortem characterizations were carried out for both electrodes. The performance degradation is attributed to the corrosion of the mild steel and the formation of multiphase iron–vanadium-based oxides at the cathode end, reducing the iron ion concentration. Thus, the present studies provide a microscopic understanding of capacity fading in iron ion batteries and may assist in designing suitable electrode materials for the improved electrochemical response.

我们在环境条件下使用低碳钢 (MS) 作为负极、五氧化二钒作为正极、在基于四乙二醇二甲醚 (TGDME) 的溶剂中使用高氯酸亚铁水合物制造可充电铁离子电池 (RIIB)，没有任何惰性气氛并研究性能下降。该电池在 33 mAg ^-1下表现出 ~ 120 mAh g ^-1比容量当前密度。初始容量在 30 次循环后衰减至约 41%。拆开电池，对两个电极进行验尸表征。性能下降归因于低碳钢的腐蚀和阴极端铁钒基多相氧化物的形成，降低了铁离子浓度。因此，本研究提供了对铁离子电池容量衰减的微观理解，并可能有助于设计合适的电极材料以改善电化学响应。