Robust NASICON-type iron-based Na4Fe3(PO4)2(P2O7) cathode for high temperature sodium-ion batteries

Heterovalent Chromium-Doped Na3Fe2(PO4)P2O7 Cathode Material with Superior Rate and Stability Performance for Sodium-Ion Storage

“…This suggests that the sodium storage reaction at the cathode is a diffusion-controlled process. 43 Therefore, the diffusion coefficient of sodium ions during the electrode reaction can be calculated by the following Randles−Sevcik equation 44,45 I n AD Cv 2.69 10…”

“…This suggests that the sodium storage reaction at the cathode is a diffusion-controlled process . Therefore, the diffusion coefficient of sodium ions during the electrode reaction can be calculated by the following Randles–Sevcik equation , I normalp = 2.69 × 10 5 n 3 / 2 A D N a + 1 / 2 C v 1 / 2 where I p denotes the peak current, n represents the quantity of charge transfer, A represents the effective contact area of the electrode and electrolyte, C represents the concentration of sodium ions, and v stands for the scanning speed. The results of the D Na + values for Cr0.2-NFPP and NFPP based on the above equations are calculated as follows.…”

Optimization Strategies Toward Functional Sodium‐Ion Batteries

“…As a result of nanostructure regulation and the dual‐nanocarbon coating, high rate performance (80.7 mAh g −1 at 20 C) and ultra‐stable cyclic stability of 30 000 cycles at 20 C with 86.7% capacity retention can be achieved. [ 53 ] Nanostructuring of cathode materials is an optimal technique for all three types of cathode because it provides shorter electronic/ionic diffusion pathways, complete infiltration of electrolytes, good conductivity, and structural integrity, leading to superior cyclic stability and rate performance. Despite enhanced electrolyte infiltration, these structures can lead to electrolyte decomposition due to side reactions.…”

Anionic Group Doping of Na4Fe3(PO4)2P2O7 Stabilizes Its Structure and Improves Electrochemical Performance for Sodium Ion Storage

“…Ji et al prepared a 3D mesoporous sponge-like structured Na 4 Fe 3 (PO 4 ) 2 P 2 O 7 cathode material with in situ carbon and graphene double encapsulation. 28 The amorphous carbon layer limits material growth, while the addition of graphene constructs conductive pathways. The modified material exhibits good cycling and thermal stability.…”