Role of Amorphous Phases in Enhancing Performances of Electrode Materials for Alkali Ion Batteries

Abstract

As one of the most competitive energy storage systems owing to their high energy density, conversion efficiency, long lifetime, and environment friendliness, alkali ion batteries have been widely used and continue to exhibit their potential to be the crucial components of future energy technologies. To further improve electrochemical performances of alkali ion batteries, great efforts have been put into the development of advanced electrode materials. However, scientists are facing great challenges in developing superior electrode materials due to the limitation of the existing technologies. Therefore, we recently chose a different route, that is, the amorphization engineering, to develop high-performance electrodes. Here, we review some recent studies about the role of amorphous phases in promoting electrochemical performances of both cathodes and anodes for alkali ion batteries. In addition, we review some progress in revealing the microscopic mechanisms of the increased ionic/electronic transport as well as the enhanced structural stability in electrodes, achieved by amorphization engineering.

Controllable Synthesis of Anatase TiO2 Nanosheets Grown on Amorphous TiO2/C Frameworks for Ultrafast Pseudocapacitive Sodium Storage

“…In contrast to long-range ordered crystalline materials, disordered amorphous materials show loose structures and large free volume that can act as ion reservoirs and channels to enhance intercalation kinetics. 21,22 In fact, amorphous materials have recently been confirmed to possess better Li + intercalation pseudocapacitance than their crystalline counterparts. 21,23 However, it is intriguing that there have been no reports on amorphous intercalation pseudocapacitive materials as SIB anodes, which may be due to the relatively poor conductivity of amorphous materials.…”

Na2Fe2OS2, a new earth abundant oxysulphide cathode material for Na-ion batteries

“…This feature could help maintain the electrochemical properties of the material upon long-term cycling and shows that the crystallinity is not a prerequisite for good cyclability in this material. Amorphization has been shown to play a crucial role in promoting the electrochemical performance of Na-Fe-P-O based cathodes, 76,77 and, in this regard, it would also be interesting to further study sodium oxysulphide glass materials for Na-ion batteries. Oxysulphides represent a very promising opportunity as cathode materials for sodium-ion batteries, with the possibility for both transition metal cations and sulphur anions to participate in the redox process to enhance overall capacity.…”

In Situ Probing Potassium-ion Intercalation-induced Amorphization in Crystalline Iron Phosphate Cathode Materials

“…Traditional electrode materials designed for Li-ion batteries may not be ideal to allow reversible charge storage of Na and K ions due to their different size, mass and reactivity. Intensive efforts have been focused to develop new electrode nanostructures for these battery systems 4 .…”