High specific capacity of Li3V2(PO4)3/C glass-ceramic with ultralow carbon content

Li3V2(PO4)3 glass-ceramic, as an intrinsic insulator, necessitates compositing with conductive carbon to function as a cathode for energy storage in lithium-ion batteries, inevitably reducing the specific energy of the final devices. This study synthesized Li3V2(PO4)3/C composite with an ultralow carbon content (1.39 wt.%) using a sol-gel method with glucomannan as a soft template. The Li3V2(PO4)3/C composite cathode achieved an initial discharge specific capacity of 128.22 mAh g−1 at 0.1 C, which is 97.14% of the theoretical specific capacity. Additionally, it demonstrated excellent rate capabilities, with 106.20 mAh g−1 at 5 C and 78.91 mAh g−1 at 10 C, as well as long-term cycling stability, with 114.94 mAh g−1 at 2 C and retaining 92.09% capacity after 500 cycles. The ultralow carbon content feature will contribute to the commercialization of cathodes. This work provides a novel direction for the design and fabrication of new electrode materials.