文摘
The design and facile fabrication of CrTi-based anode materials with long-life, good safety, and low cost are strongly desired for lithium-ion batteries. In this study, we adopt the sol–gel method using glucose as carbon source to synthesize carbon-coated Li5Cr7Ti6O25. The effects of a carbon layer in Li5Cr7Ti6O25/C on electrochemical properties are focused through comparing carbon-coated Li5Cr7Ti6O25 with carbon-free Li5Cr7Ti6O25. Electrochemical tests show that Li5Cr7Ti6O25/C possesses better cycling and rate performances than those of carbon-free Li5Cr7Ti6O25. Cycled at 500 mA gp>–1p>, Li5Cr7Ti6O25/C delivers a high specific capacity of 111.6 mAh gp>–1p> with 13% capacity loss after 200 cycles. In contrast, Li5Cr7Ti6O25 only exhibits a specific capacity of 93.6 mAh gp>–1p> at 500 mA gp>–1p> with 19% capacity loss after 200 cycles. The preeminent electrochemical property of Li5Cr7Ti6O25/C is ascribed to the amorphous carbon coating layer. This carbon layer can remarkably facilitate the transportation of electrons and ions in Li5Cr7Ti6O25. Furthermore, the lithiation/delithiation behavior of Li5Cr7Ti6O25/C is also investigated by advanced in situ X-ray diffraction technique, and the results verify that Li5Cr7Ti6O25/C possesses a highly reversible structural change during the charge/discharge process.