摘要

Li2CO3 modified carbon microbead composites (LCO/CMB-T) with different covering amount are prepared by solvent evaporation and dipping method. LiCH3COO are first used as lithium source, which can provide a precise control of Li2CO3 amount through varying dipping times or solution concentration. The morphology, structure, and covering amount are characterized by means of X-ray diffraction (XRD), scanning electron microscope (SEM), and atomic absorption spectrometer (AAS). The dipping process can produce the samples with better surface coverage, more uniform coating, and higher Li2CO3 crystallinity, while the appropriate amount of Li2CO3 can help to decrease initial irreversible capacity and improve cell performance. Here, the sample with 1.07 % Li2CO3 prepared by dipping method shows the highest initial discharge capacity of 353.7 mAh g(-1) and coulombic efficiency of 89.5 %. The capacity retention is up to 82.1 % after 30 cycles.

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