Unlocking Charge Transfer Limitation in NASICON Structured Na₃V₂(PO₄)₃ Cathode via Trace Carbon Incorporation

Abstract

NASICON‐type cathode with remarkable ionic conductivity is perspective candidate for fast‐charging sodium‐ion battery. However, severely restricted by low electrical conductivity and poor interfacial kinetics, it usually delivers poor charge transfer kinetics. Different from traditional carbon compositing with high carbon contents, herein, a trace carbon incorporation tactic is proposed based on a typical NASICON‐structured Na3V2(PO4)3. First, particle‐growth process of Na3V2(PO4)3 is regulated via incorporating carbon dot, significantly reducing its particle size to shorten charge diffusion path. Second, electrical conductivity of Na3V2(PO4)3 is improved without sacrificing its high electrochemical activity due to the incorporated trace carbon content (0.76 wt.%). Third, Na3V2(PO4)3‐electrolyte interface structure is optimized by abundant functional groups from the incorporated carbon dot, enabling a thin and stable NaF‐rich CEI layer to boost interface kinetics. As a result, carbon dot endows Na3V2(PO4)3 with ultrastable cyclability up to 20 k cycles (capacity retention of 98.4%) and excellent rate capability (up to 200 C) in half cell, as well as high energy density (368.7 Wh kg−1) and fast charging property (≈110.2 s per charging with 250.8 Wh kg−1 input) in full cell. This study carves a new path for developing fast‐charging cathode, as is increasingly desired for present energy storage applications.

Win–win strategy: zinc-ion anchoring crosslinked hydrogels and regulating electronic structure to achieve V3+/V4+/V5+ redox reaction of Na3V2(PO4)3 with high thermal stability and zero strain characteristics

“…4h–j illustrate a comparison of the performance of our samples with those of previous works from different perspectives. It is evident that the NVP/C-Zn0.07@CHACC sample outperforms those of many existing works in terms of rate performance, 14,24–32 discharge specific energy, 15,26,28,33–36 and maximum cycle number achievable. 15,37–44 Particularly, the appearance of the second plateau greatly enhances the discharge specific energy of the modified sample, suggesting that batteries assembled with NVP/C-Zn0.07@CHACC could provide more energy within the same volume for future practical applications.…”

Pre‐Doping of Dual‐Functional Sodium to Weaken Fe─S Bond and Stabilize Interfacial Chemistry for High‐Rate Reversible Sodium Storage

“…The sodium storage performances of NFS-1 in full cells are further conducted pairing with the commercial Na 3 V 2 (PO 4 ) 3 (Figure 5a), which exhibited pure NASICON structure, [55] spherical porous morphology and stable electrochemical properties (Figure S19, Supporting Information). Both current density and capacity are calculated based on the mass of the anode material.…”