LiCoO2 nanoplates with exposed (001) planes and high rate capability for lithium-ion batteries

We report the synthesis of near-uniform LiCoO2 nanoplates by a two-step approach in which beta-Co(OH)(2) nanoplates are synthesized by co-precipitation and then transformed into LiCoO2 nanoplates by solid state reaction at 750 A degrees C for 3 hours. Characterization by high-resolution transmission electron microscopy (HRTEM) and electron diffraction (ED) reveal that the as-prepared LiCoO2 nanoplates are covered with many cracks and have exposed (001) planes. The electrochemical performance of the LiCoO2 nanoplates was investigated by galvanostatic tests. The capacity of LiCoO2 nanoplates stabilized at 123 mA center dot h/g at a rate of 100 mA/g and 113 mA center dot h/g at a rate of 1000 mA/g after 100 cycles. The excellent rate capability of the LiCoO2 nanoplates results from cracks which are perpendicular to the (001) plane and favor fast Li+ transportation. In addition, compared with other methods of synthesis of LiCoO2 the time of the solid reaction state is significantly shorter even at relatively low temperatures, which means the energy consumption in preparing LiCoO2 is greatly decreased. The controllable synthesis of LiCoO2 nanoplates with exposed (001) plane paves an effective way to develop layered cathode materials with high rate capabilities for use in Li-ion batteries.