Abstract：High voltage Li- and Mn-rich layered oxide (LMRO) electrodes with different amount of conductive carbon black Super P were investigated to explore the effect of carbon black on electrochemical performance of the electrode and scanning electron microscopy (SEM) and electrochemical impedance spectroscopy (EIS) were utilized to study the internal reason why the amount of Super P affects the performance of the electrode. The results show that the performance of cycle stability and high-rate capability of LMRO electrodes exhibit the tendency of increasing first and then decreasing with increase of Super P content, while the optimum performance of electrodes is obtained at 5% (mass fraction,the same below). With the increase of Super P content, electronic contact between LMRO particles and Super P particles can be improved, electrically conductive network can be constructed, resistance between electrode components can be decreased, and electrode polarization can be reduced. However, when the content is higher than 5%, Super P particles are easily agglomerated, which is undesirable for further improving the conductivity of electrode.
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