Re-envisioning the Key Factors of Magnesium Metal Anodes for Rechargeable Magnesium Batteries

Abstract

The growing interest in rechargeable magnesium batteries (RMBs) stems from the demands for energy storage technologies with safety, sustainability, and high energy density. However, the ambiguous mechanism of the Mg metal anode during the electrochemical and manufacturing processes severely impedes the pursuit of superior performance. Those commonly overlooked bottlenecks in pure Mg or Mg alloy metal anodes should be emphasized and deserve more consideration. In this Review, a brand-new perspective is emerging to reveal the opportunity for overcoming the long-standing obstacles hindering the development of RMBs. Herein, we comprehensively discuss the recent efforts to relieve the interfacial incompatibility between Mg metal anodes and electrolytes, including the pursuit of new electrolyte, interfacial modification, mechanism exploration, etc. Additionally, we put forth an unconventional research direction to promote the development of RMBs, namely exploring Mg metal anodes in terms of their electrochemical and mechanical properties. In closing, our proposals for addressing the key factors and intractable issues with Mg metal anode are brought forward.

Novel Electrospun Sn-Based Composite Cathodes Exhibiting Extended Cycle Life for Hybrid Magnesium–Lithium Batteries

“…Not only do they fulfill the theoretical energy density requisites for contemporary portable devices, but they also sidestep the persistent challenge of dendrite proliferation characteristic of lithium systems. 10,11 However, MIBs face stymieing constraints stemming from a paucity of suitable cathode materials. The strong Coulombic interactions between Mg 2+ ions and host structures engender protracted migration and diffusion processes, culminating in substantial polarization and suboptimal electrochemical performance.…”

“…This exigent need has steered researchers toward investigating alternative high-capacity, safe, and dependable battery systems, among which rechargeable magnesium-ion batteries (MIBs) stand out as a particularly promising candidate. Not only do they fulfill the theoretical energy density requisites for contemporary portable devices, but they also sidestep the persistent challenge of dendrite proliferation characteristic of lithium systems. , However, MIBs face stymieing constraints stemming from a paucity of suitable cathode materials. The strong Coulombic interactions between Mg 2+ ions and host structures engender protracted migration and diffusion processes, culminating in substantial polarization and suboptimal electrochemical performance. , This novel battery system is highly regarded for its unique performance advantages, specifically in terms of its high volumetric energy density, remarkable cycling durability, and excellent kinetic responsiveness. − In view of these advantages, magnesium–lithium batteries (MLIBs) show great potential for application and development in the future field of high-power storage devices and power batteries.…”

Lightweight 3D Lithiophilic Graphene Aerogel Current Collectors for Lithium Metal Anodes

“…Lithium metal is regarded as one of the most promising candidates for next-generation high-energy-density batteries owing to its high theoretical capacity (3860 mA h g −1 ) and low potential (−3.04 V vs. SHE), and thus has attracted considerable research attention in recent years [1][2][3][4]. However, the practical application of lithium metal anodes is still hindered due to the uncontrollable dendritic growth of lithium [5][6][7][8]. The accumulation of "dead" Li increases the risk of internal short circuits by piercing the separators during cyclic processes [9].…”

Microstructure of Pure Magnesium and AZ31 Magnesium Alloy Anodes after Discharge/Charge Cycles for Rechargeable Magnesium Batteries

“…However, reports about the stripping/plating behavior and the resultant microstructure of the Mg metal anodes after cycles are scarce but are crucial to the future development of Mg battery systems. 24 Recently, Liu et al 25 studied the stripping behavior of pure Mg electrodes in a 0.4 M all phenyl complex (APC) electrolyte under different discharge current densities. The relationship between the uniformity of the stripping morphology of pure Mg and the discharge current density shows a volcano-shaped plot.…”