The Distance Between Phosphate‐Based Polyanionic Compounds and Their Practical Application For Sodium‐Ion Batteries

Abstract

Sodium‐ion batteries (SIBs) are a viable alternative to meet the requirements of future large‐scale energy storage systems due to the uniform distribution and abundant sodium resources. Among the various cathode materials for SIBs, phosphate‐based polyanionic compounds exhibit excellent sodium‐storage properties, such as high operation voltage, remarkable structural stability, and superior safety. However, their undesirable electronic conductivities and specific capacities limited their application in large‐scale energy storage systems. Herein, the development history and recent progress of phosphate‐based polyanionic cathodes are first overviewed. Subsequently, the effective modification strategies of phosphate‐based polyanionic cathodes are summarized toward high‐performance SIBs, including surface coating, morphological control, ion doping, and electrolyte optimization. Besides, the electrochemical performance, cost, and industrialization analysis of phosphate‐based polyanionic cathodes for SIBs are discussed for accelerating commercialization development. Finally, the future directions of phosphate‐based polyanionic cathodes are comprehensively concluded. We believe that this review can provide instructive insight into developing practical phosphate‐based polyanionic cathodes for SIBs.This article is protected by copyright. All rights reserved

Boosting Multielectron Reaction Stability of Sodium Vanadium Phosphate by High-Entropy Substitution

“…Unfortunately, its unsatisfactory theoretical capacity of 117 mAh g −1 results in a limited energy density. 10 Until now, the prevailing approach employed to achieve a large capacity of NVP has centered on augmenting electron transfer numbers by activating the redox couples of V 5+ /V 4+ and V 3+ / V 2+ . The V 3+ /V 2+ redox reaction at ca.…”

“…The reported cathodes can be broadly classified into organic compounds, layered transition metal oxides (LTMOs), Prussian blue analogues (PBAs), and polyanionic compounds (PACs). − Among these, a sodium superionic conductor (NASICON) structured PAC of Na 3 V 2 (PO 4 ) 3 (NVP) has attracted extensive attention due to its acceptable redox potential of 3.4 V (vs. Na + /Na) based on the V 4+ /V 3+ redox couple, robust crystalline structure, and open three-dimensional framework. Unfortunately, its unsatisfactory theoretical capacity of 117 mAh g –1 results in a limited energy density . Until now, the prevailing approach employed to achieve a large capacity of NVP has centered on augmenting electron transfer numbers by activating the redox couples of V 5+ /V 4+ and V 3+ /V 2+ .…”

Emerging high voltage V4+/V5+ redox reactions in Na3V2(PO4)3-based cathodes for sodium-ion batteries

“…For the anode materials, hard carbons (HCs) with a low void, highly disordered structure, large layer space and achievable reversible capacity above 300 mA h g −1 , are considered to be the most promising anode materials for SIBs and extensively applied both in laboratory research and the market. 10,11 As for the cathode side, the widely studied materials of SIBs at present are layered transition metal (TM) oxides, 12–15 polyanionic materials, 16–19 Prussian Blue, 20–22 and organic materials. 23–25 Polyanionic materials, with a general formula of Na x M y (X a O b ) z Z w (where M represents one or more transition metals such as Ti, V, Cr, Mn, Fe, Co, Ni, etc.…”

Construction of metal–organic framework-derived Al-doped Na 3V 2(PO 4) 3 cathode materials for high-performance rechargeable Na-ion batteries

“…Carbon coating or nanocrystallization can decrease the tap density of the electrode material and reduce the volumetric specific energy of the full battery [36,37] . Ion doping is considered an efficient strategy for enhancing the inherent electronic conductivity and ion diffusion kinetics of NVP [38,39] . This strategy includes cation and anion doping.…”