Optimized LiVOPO4 for cathodes in Li-ion rechargeable batteries

Improvement of the rate properties of orthorhombic LiVOPO₄ by using a milling approach and acetylene black additives as electronic binder is investigated. The average particle size of orthorhombic LiVOPO₄ was reduced from 12.0 μm to 6.1 μm by milling process by which the Li intercalation capacity into LiVOPO₄ increased to 40 mAhg⁻¹ at 0.4 mAcm⁻² (C/5). At an optimized acetylene black amount of 15 wt.%, a better uniformity in particle size distribution and dispersion of the current distribution was obtained. Thus, enhancing the kinetic performance a fairly large reversible intercalation capacity of Li was achieved with values of 100 and 60 mAhg⁻¹ at high rate conditions of C/5 (0.4 mAcm⁻²) and 1C (2 mAcm⁻²), respectively. Paper presented at the International Conference on Functional Materials and Devices 2005, Kuala Lumpur, Malaysia, June 6 – 8, 2005.