Towards high-performance phosphate-based polyanion-type materials for sodium-ion batteries

A Comparative Study of Mixed Phosphate‐Pyrophosphate Materials for Aqueous and Non‐Aqueous Na‐ion Batteries

“…This is mainly due to the high electrode potential of these metals, and/or their relative abundance and low‐cost [10] . According to several reports, Na 4 X 3 (PO 4 ) 2 P 2 O 7 (X (II) =Fe, Mn, Co, Ni,) are very attractive positive electrodes for Na‐ion batteries [7,11–13] . They typically crystalize in Pna 2 1 (No.…”

“…[10] According to several reports, Na 4 X 3 (PO 4 ) 2 P 2 O 7 (X (II) = Fe, Mn, Co, Ni,) are very attractive positive electrodes for Na-ion batteries. [7,[11][12][13] They typically crystalize in Pna2 1 (No. 33) space group, and the crystal framework contains infinite [X 3 P 2 O 13 ] ∞ layers parallel to b,c plane, which comprise three [XO 6 ] octahedra, two [PO 4 ] tetrahedra, and [P 2 O 7 ] groups along a-axis.…”

The Progress of Hard Carbon as an Anode Material in Sodium-Ion Batteries

“…( b ) Rate performances at 0.05, 0.1, 0.2, 0.5, 1.0, 2.0, 5.0, 10, 20, and 50 A g −1 , respectively. ( c ) The electrochemical performance of different HC materials [ 15 , 23 , 37 , 44 , 45 , 47 , 48 , 49 , 50 , 51 , 52 ]. ( d ) The long-term cycling performance of HCM-1300-ZBE at 2 A g −1 .…”

“…Anode materials play an important role in facilitating sodium-ion batteries with outstanding electrochemical performance. The design of novel anode materials with excellent performance and low cost can accelerate the commercialization of sodium-ion batteries [ 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 ]. Among the many anode electrode materials of sodium-ion batteries, hard carbon materials have the superiority of high capacity, low price, and low working voltage, and their unique structure is conducive to sodium-ion adsorption and reversible embedding/removal, showing excellent sodium storage performance, making them the most likely anode materials to be commercialized [ 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 ].…”

Synergistic Coupling Effect of Electronic Conductivity and Interphase Compatibility on High-Voltage Na3V2(PO4)2F3 Cathodes

“…Sodium-ion batteries (SIBs) have attracted tremendous attention as one of the most promising next-generation rechargeable battery systems for grid-scale energy storage, on account of the low cost and natural abundance of sodium resources. – The property and cost of SIBs are mainly determined by the applied cathode materials. – A wide range of existing cathodes, such as layered transition-metal oxides, phosphate compounds, Prussian Blue derivatives, and organic materials, have been substantially investigated to boost the development of high-performance and low-cost SIBs. – Among them, sodium vanadium fluorophosphate Na 3 V 2 (PO 4 ) 2 F 3 (NVPF), which has a high working voltage of about 3.9 V vs Na + /Na and a considerable theoretical specific capacity of 128 mA h g –1 , is one of the most prospective polyanionic cathode materials for SIBs owing to its superior cycling stability resulting from the intrinsic structural stability and high Madelung energy. – However, an unstable cathode electrolyte interface (CEI) layer is inevitably formed at a voltage greater than 4.2 V vs Na + /Na because of the mismatched interface between high-voltage cathode materials and narrow electrochemical windows of the electrolyte. These detrimental limitations are fundamentally related to the successive decomposition of electrolytes and undesirably adverse reaction products, exacerbating the interphase incompatibility toward NVPF. , So, the structure and property of the CEI layer have a significant impact on the cycling life and rate performance of SIBs.…”