Long Cycle Life TiC Anode Fabricated via High-Energy Ball Mill for Li-Ion Battery

Abstract

Nano-TiC and nano-WC anodes for Li-ion battery were manufactured by high-energy ball milling. Pure titanium powder and toluene are mixed with a high-energy ball mill to prepare TiC powder. The powder is calcined at 750°C/1 h and secondary ball milled to make a negative electrode for lithium-ion battery. The phase composition and micromorphology of TiC powder are analyzed and observed, and the charge-discharge cycle performance of TiC anode material is tested. The results show that there are TiH2 and WC impurities in the product after primary ball milling. After calcination and secondary ball milling, TiH2 impurities are removed and the TiC grain size is refined, and TiC powder is obtained with a grain size of 12.5 nm. The specific discharge capacity of the TiC anode is stable during the long cycle discharge. When the current density is 1 A/g, the specific discharge capacity can still be maintained at 110 mAh/g after 3000 cycles. The results show that TiC anode materials have excellent long-cycle performance and could be used as the frame material of Si anode materials. Nano-WC powders are prepared by a ball milling method to investigate the effect of WC impurities on the performance of TiC lithium batteries. The charge and discharge capacity at 0.5 A/g current density is similar to that of TiC anode. After 2000 cycles, the discharge-specific capacity is about 100 mA/g, which is slightly lower than TiC, and the final capacity is maintained at 230 mA/g, but its low discharge capacity affects the performance of the TiC battery after a long ball milling. The results show that the performance of the TiC anode after the first 50 h of ball milling is poor. The main reason is the agglomeration of TiC nanoparticles.