XIA Jing, GAO Yuan, LI Shuxiang, LI Shouyi, GAO Long, ZHANG Dakui, ZHANG Baolei
In order to optimize the preparation of sodium-ion batteries and improve the performance of hard carbon anode materials, the structural and electrochemical properties of commercial hard carbon materials from three leading manufacturers (Kuraray, Baisige, and BTR) were analyzed, including morphology, particle size, crystalline structure, pore characteristic, compacted density, specific capacity, cycling stability, rate capability, and diffusion kinetics. The results reveal that Kuraray's hard carbon demonstrates the smallest particle size and specific surface area, the most concentrated pore size distribution, and the highest compacted density. Baisige's hard carbon exhibits the highest structural disorder, while BTR's hard carbon shows the largest particle size and specific surface area. The initial reversible specific capacities of the hard carbon from Baisige, Kuraray and BTR are 319.0, 303.3 and 301.0 mAh/g. Notably, Kuraray's hard carbon demonstrates the highest capacity retention (95.7% after 250 cycles) and the best rate capability (232.0 mAh/g at 10 C). During the electrochemical reaction process, Kuraray's hard carbon is predominantly surface-controlled, while Baisige and BTR's systems are mainly diffusion-controlled.
