In this paper, a series of Li₃V₂(PO₄)₃/C composite nanofibers is prepared by a facile and environmentally friendly electrospinning method and calcined under different temperatures. The LVP nanofiber calcined under 900 ℃ exhibits the best electrochemical performance. The bicontinuous morphologies of LVP/CNF are the fibers shrunk and the LVP crystals simultaneously grown. At the range of 3.0–4.3 V, LVP/CNF obtained under 900 ℃ delivers the initial capacity of 135 mAh/g, close to the theoretical capacity of LVP. Even at high current density, the sample of LVP/CNF still presents good electrochemical performance.

Cobalt-based sulfides have emerged as promising candidates for next-generation high-performance anode materials for lithium-ion batteries (LIBs) due to their high theoretical specific capacity and reversible conversion reaction mechanisms. However, their practical application is hindered by volume expansion effects and relatively low rate performance. Guided by theoretical principles, this study synthesizes nanoscale Bi/CoS-C and Bi/Co₄S₃-C (denoted as Bi/CS-C) composite materials using Co and Bi₂S₃ as precursors via a solid-state ball milling method. The electrochemical properties of these materials were systematically investigated. When employed as anodes for LIBs, Bi/CoS-C and Bi/CS-C exhibit excellent rate capabilities. At current densities of 0.1, 0.5, 1, 4, and 10 A/g, the reversible capacities of Bi/CoS-C were 939.2, 730.7, 655.6, 508.1, and 319 mAh/g, respectively. In contrast, Bi/CS-C exhibited reversible capacities of 760.4, 637.6, 591.9, 484.3, and 295.4 mAh/g, respectively. Moreover, Co₄S₃, as an active component, enables superior long-cycle performance compared to CoS. After 300 cycles at 0.2 A/g, the Bi/CoS-C and Bi/CS-C electrodes retained capacities of 193.1 and 788.8 mAh/g, respectively. This study demonstrates that nanostructure design and carbon-based composite materials can effectively mitigate the volume expansion issue of cobalt-based sulfides, thereby enhancing their rate performance and cycling stability. This strategy provides new insights for the development of high-performance anode materials for lithium-ion batteries and is expected to accelerate their practical application in next-generation energy storage devices.