High energy density rechargeable magnesium battery using earth-abundant and non-toxic elements

Abstract

Rechargeable magnesium batteries are poised to be viable candidates for large-scale energy storage devices in smart grid communities and electric vehicles. However, the energy density of previously proposed rechargeable magnesium batteries is low, limited mainly by the cathode materials. Here, we present new design approaches for the cathode in order to realize a high-energy-density rechargeable magnesium battery system. Ion-exchanged MgFeSiO4 demonstrates a high reversible capacity exceeding 300 mAh·g−1 at a voltage of approximately 2.4 V vs. Mg. Further, the electronic and crystal structure of ion-exchanged MgFeSiO4 changes during the charging and discharging processes, which demonstrates the (de)insertion of magnesium in the host structure. The combination of ion-exchanged MgFeSiO4 with a magnesium bis(trifluoromethylsulfonyl)imide–triglyme electrolyte system proposed in this work provides a low-cost and practical rechargeable magnesium battery with high energy density, free from corrosion and safety problems.

Room Temperature Magnesium Electrodeposition from Glyme-Coordinated Ammonium Amide Electrolytes

“…Without ILs, the G3 solution of Mg(Tf 2 N) 2 shows as large current density as IL/G2 or IL/G4 mixture. 18,19 Moreover, the IL/G3 sample kept in a glove box for 7 days after mixing changed to yellowish from colorless while the others remained fairly colorless (see Fig. 8).…”

“…[16][17][18][19] We have also reported an amide-containing glyme-IL solution with which room temperature electrodeposition of Mg metal was successfully demonstrated. In these Mg 2+ -amide-containing glyme solutions, however, sizable amounts of free glyme molecules exists, as in IL-free glyme electrolytes, and thus all the reported electrolytes are either volatile and/or have limited anodic stability to some extent.…”

The Effect of the Cyclic Ether Additives to the Ethereal Electrolyte Solutions for Mg Secondary Battery

“…Recently, however, it was reported that the reversible Mg plating and stripping was achieved with Mg(N(CF 3 SO 2 ) 2 ) 2 (Mg(TFSA) 2 ) dissolved in triethyleneglycol dimethyl ether (triglyme) based solutions. 8,9 Since the electrolyte solution shows the high ionic conductivity of 10 ¹3 S cm ¹1 at room temperature and relatively high oxidation stability, the glyme based solutions will be the new standard for the Mg secondary batteries' electrolyte.…”

Alkali metal ion storage properties of sulphur and phosphorous molecules encapsulated in nanometer size carbon cylindrical pores

“…However, new energy source with higher capacity and better rate performance is required because LIBs are not good enough for larger and higher power machines such as electric vehicles. Recently, metal-air, [11][12][13][14] lithium-sulfur (LIS), [15][16][17][18][19][20] sodium-ion [21][22][23][24][25] batteries and others [26][27][28][29] have been attracting much attention as post-LIB energy devices.…”