High‐Energy‐Density Aqueous Magnesium‐Ion Battery Based on a Carbon‐Coated FeVO₄ Anode and a Mg‐OMS‐1 Cathode

Abstract

Porous FeVO is prepared by hydrothermal method and further modified by coating with carbon to obtain FeVO /C with a hierarchical pore structure. FeVO /C is used as an anodic electrode in aqueous rechargeable magnesium-ion batteries. The FeVO /C material not only has improved electrical conductivity as a result of the carbon coating layer, but also has an increased specific surface area as a result of the hierarchical pore structure, which is beneficial for magnesium-ion insertion/deinsertion. Therefore, an aqueous rechargeable magnesium-ion full battery is successfully constructed with FeVO /C as the anode, Mg-OMS-1 (OMS=octahedral molecular sieves) as the cathode, and 1.0 mol L MgSO as the electrolyte. The discharge capacity of the Mg-OMS-1//FeVO /C aqueous battery is 58.9 mAh g at a current density of 100 mA g ; this value is obtained by calculating the total mass of two electrodes and the capacity retention rate of this device is 97.7 % after 100 cycles, with almost 100 % coulombic efficiency, which indicates that the system has a good electrochemical reversibility. Additionally, this system can achieve a high energy density of 70.4 Wh kg , which provides powerful evidence that an aqueous magnesium-ion battery is possible.

Dendrite Growth Suppression by Zn2+‐Integrated Nafion Ionomer Membranes: Beyond Porous Separators toward Aqueous Zn/V2O5 Batteries with Extended Cycle Life

“…This has opened up new challenges as well as opportunities in the realization of more efficient aqueous ZIBs (AZIBs) with a variety of other cathode materials . Although other chemistries based on Al/Al 3+ and Mg/Mg 2+ have been proposed, the Zn/Zn 2+ systems are considered to be the leading candidate due to the high theoretical capacity (820 mAh g −1 ), low redox potential (−0.76 V vs standard hydrogen electrode [SHE]), natural abundance, and low cost of Zn metal …”

V2O5 as magnesium cathode material with extended cyclic stability

“…The specific discharge capacity was estimated to be 300 mA h g -1 with capacity retention of 92 % after 10000 scans and coulombic efficiency of 100 %. The capacity performance of this electrode is enhanced as compared to AACVD V 2 O 5 at 500 °C [7], FeVO 4 in 1 M Mg SO 4 (300 mA h g -1 , efficiency: 100 % after 50 cycles [15]) and magnesium manganese oxide sieves in 0.5 M MgCl 2 (300 mA h g -1 , efficiency: 100 % after 300 cycles [16]). Finally, the shape of the curves remained unchanged for the first to the 10000th proposing good electrode stability.…”

High‐Energy Aqueous Magnesium Hybrid Full Batteries Enabled by Carrier‐Hosting Potential Compensation

“…This generally results in discharge voltage plateaus below 1.00 Vand low capacity of aqueous magnesium-ion batteries. [10] In contrast, with ar elatively low cost and small migration barrier,t he intercalation chemistry of monovalent Na + carriers proceeds much more easily in host materials. [11] Thes maller polarization of Na + (de)intercalation usually affords ahigher hosting potential in electrodes compared to the case of Mg 2+ (de)intercalation.…”