Moving toward high‐energy rechargeable Mg batteries: Status and challenges

Abstract

Lithium-ion batteries (LIBs) have gained significant market share in the field of consumer electronics, grid storage, and hybrid electric vehicles, because of its exceptional energy densities per unit volume (area or weight) compared to other electrochemical energy storage systems. However, they do approach its maximum practical capacities and efforts are underway to explore future battery systems with enhanced energy density than LIBs. There has been growing interest in incorporating multivalent ions such as Zn 2+ , Mg 2+ , and Al 3+ , since they offer greater volumetric energy densities than its monovalent counterparts like LIBs and sodium-ion batteries. It has long been acknowledged that replacing lithium with magnesium (Mg) ions in battery systems has many potential benefits such as low cost, excellent rate capability, high energy density, ease of handling, and eco-friendly. Yet, a few breakthroughs has been made in the advancement of rechargeable magnesium batteries (RMBs) since its first discovery in 2000. The success of RMBs has been hindered by the slow electrode kinetics and also the formation of passive layers on Mg metal surfaces seriously affecting its performance during Mg 2+ ion magnesiation/demagnesiation. This chapter provides comprehensive knowledge on the background of rechargeable Mg batteries, principles, and cell configuration, discussing key advancements made in the last two decades in terms of its electrode materials and electrolytes. Finally, a brief note on future research strategies is outlined. Highlights• Mg-ion batteries may replace Li-ion batteries to meet the demands of both consumer and industrial energy storage.

Stability and Semiconducting Behavior of Magnesium Polysulfides by Nonequivalent sp3 Hybridizations

“…The contributions of pV and entropy are not considered at zero pressure and zero temperature. As shown in Figure S6, the calculated discharge voltages for all Mg–S compounds are around 1.6 V, slightly higher than the experimental discharge platform, indicating that the discharge reaction is highly affected by the sluggish electrode kinetics …”

Recent progress in structural modification of polymer gel electrolytes for use in solid-state zinc-ion batteries

“…[1][2][3][4][5] Some "beyond lithium-ion" technologies, including sodium-, potassium-, magnesium-and zinc-ion batteries, are popular nowadays. [6][7][8][9][10][11][12][13][14][15][16] Among the modern energy storage systems, zinc-ion batteries have a high volumetric energy density, high safety, low cost and low redox potential. [17][18][19] However, there are still some difficulties in the research of zinc-ion batteries, especially for those with aqueous electrolytes, which include the hydrogen evolution reaction, oxygen absorption corrosion and dendrite growth at the zinc anode that hinder the development of zinc-ion batteries.…”