Modified Pechini-derived Na3V2(PO4)3/C with superior low-temperature performance for sodium-ion batteries

Abstract

Sodium-ion batteries (SIB) have attracted significant attention as promising alternatives to lithium-ion batteries, due to the abundance, low cost, and environmental compatibility of sodium resources. Among various SIB cathode materials, NASICON-type Na₃V₂(PO₄)₃ (NVP) stands out for its stable 3D framework and fast Na⁺ diffusion kinetics. However, its inherently low electronic conductivity has posed challenges for practical implementation. Promising in this context, the NASICON-structure NVP nanomaterial was successfully synthesized using a modified Pechini method. Owing to the reduced particle size and carbon coating, the cathode exhibits exceptional performance, demonstrating a capacity of 74.13 mAh g⁻¹ at 0.2 C even at −20 °C, which is 76.26% of its room-temperature capacity. Furthermore, the electrode retained 74.99% of its room-temperature capacity at −25 °C, demonstrating outstanding low-temperature resilience. These results confirm that the modified Pechini-derived NVP/C composite is a highly promising cathode material for high-performance sodium-ion batteries operating under subzero conditions.