Nanoarchitectonics of Acicular Nanocrystal Assembly and Nanosheet Assembly for Lithium-Ion Batteries

Nanoarchitectonics of metal oxide nanocrystal electrodes were developed for lithium-ion batteries. The electrodes included copper nanoparticles and doped fluorine. For the acicular nanocrystals, charge-discharge reactions progressed at 1.8 V over 100 cycles at 100 and 10 μA. A 15-mmdiameter battery containing acicular nanocrystals showed capacity, coulomb efficiency, and specific capacity, respectively of 20 μAh, 98%, and ~242 mAh/g at 100 μA and 40 μAh, 99%, and 484 mAh/g at 10 μA. The TiO₂/SnO₂ electrode consisted of a SnO₂ sheet-assembled structure with surface layers of anatase TiO₂. The TiO₂/SnO₂ battery operated at 1.3 (100 cycles) and 1.2 (50 cycles) V at 100 and 10 μA, respectively; its capacity, coulomb efficiency, and specific capacity, respectively were 50 μAh, 98%, and 161 mAh/g at 100 μA and 200 μAh, 97-98%, and 643 mAh/g at 10 μA. The characteristic microstructure, chemical composition, and crystal faces of both materials contributed to battery performance.