The State and Challenges of Anode Materials Based on Conversion Reactions for Sodium Storage

Abstract

Sodium-ion batteries (SIBs) have huge potential for applications in large-scale energy storage systems due to their low cost and abundant sources. It is essential to develop new electrode materials for SIBs with high performance in terms of energy density, cycle life, and cost. Metal binary compounds that operate through conversion reactions hold promise as advanced anode materials for sodium storage. This Review highlights the storage mechanisms and advantages of conversion-type anode materials and summarizes their recent development. Although conversion-type anode materials have high theoretical capacities and abundant varieties, they suffer from multiple challenging obstacles to realize commercial applications, such as low reversible capacity, large voltage hysteresis, low initial coulombic efficiency, large volume changes, and low cycling stability. These key challenges are analyzed in this Review, together with emerging strategies to overcome them, including nanostructure and surface engineering, electrolyte optimization, and battery configuration designs. This Review provides pertinent insights into the prospects and challenges for conversion-type anode materials, and will inspire their further study.

Phosphorus‐Doping‐Induced Surface Vacancies of 3D Na2Ti3O7 Nanowire Arrays Enabling High‐Rate and Long‐Life Sodium Storage

“…Among them, due to their advantageous energy density and cycling life, LIBs have been widely used in electric cars, laptops, cellular telephones, and other fields . However, the relatively high cost and scarcity of lithium resources limit its application in large‐scale energy storage systems . As an alternative, SIBs are favored by researchers because of their similar properties to LIBs, and sodium resources are abundant and evenly distributed in the world .…”

“…[2,16,17] However,t he relativelyh igh cost and scarcity of lithium resources limit its application in large-scale energy storages ystems. [18,19] As an alternative, SIBs are favored by researchers because of their similarproperties to LIBs, and sodium resources are abundant and evenly distributed in the world. [8,20] The graphite anode materials commonly used for LIBs show unsatisfactory sodium storagep erformance, which is attributed to the larger ionic radius of Na + (Na + :0 .102 nm;L i + :0 .076 nm), which results in in sluggish reactionk inetics and large volume expansion during cycling.…”

C@TiO2/MoO3 Composite Nanofibers with 1T‐Phase MoS2 Nanograin Dopant and Stabilized Interfaces as Anodes for Li‐ and Na‐Ion Batteries

“…[3][4][5] By virtue of considerable reserves, the easily obtainable sodium has arousedi nterest as ap romising option for rechargeable batteries. [9,10] Therefore, it would be of great importance to develop ideal electrode materials capable of storing both Li + and Na + . [9,10] Therefore, it would be of great importance to develop ideal electrode materials capable of storing both Li + and Na + .…”

Synthesis and Electrochemical Research of Milled Antimony and Red Phosphorus Hybrid Inlaid with Graphene Sheets as Anodes for Lithium–Sodium Storage

“…In contrast, the ever-increasing consumption of lithium resource hinder the sustainable development of large-scale LIBs because of the absence of lithium on the Earth's crust and their higher prices. [2,11] Recently, sodium-ion rechargeable batteries (SIBs), as promising alternatives for LIBs, have evoked extensive scientific interest on account of nontoxicity, low cost, ubiquitous distribution, and safe operating potential. [10][11][12][13][14][15] However, the larger radius of sodium ions (1.02 Å) implies inevitable drawbacks such as inferior kinetics, low Na þ diffusivity, and drastic volume expansion during sodium uptake and removal.…”