Electrochemical Performance of Li- and Mn-Rich Cathodes in Full Cells with Prelithiated Graphite Negative Electrodes

Li- and Mn-rich layered oxide cathodes are known to suffer from capacity fading and average discharge voltage decay upon cycling. In the present study, the improved cycling stability of a Li- and Mn-rich cathode Li 1.2 Ni 0.27 Mn 0.40 Co 0.13 O 2 in full cells is reported. The electrochemical performance of the Li- and Mn-rich cathodes comprising Li 1.2 Ni 0.13 Mn 0.54 Co 0.13 O 2 and Li 1.2 Ni 0.27 Mn 0.40 Co 0.13 O 2 was tested in Li-ion full cells with graphite as anode material at 30 °C. The full cells with Li 1.2 Ni 0.13 Mn 0.54 Co 0.13 O 2 cathodes exhibited initially high capacities of about 250 mAh g 1, which fades rapidly to 130 mAh g –1 after 120 cycles at C/5 rate. However, full cells comprising Li 1.2 Ni 0.27 Mn 0.40 Co 0.13 O 2 cathodes exhibited an initial capacity of about 190 mAh g –1 with very stable cycle-life, i.e., about 185 mAh g –1 after 150 cycles at C/5 rate. Also, these cathodes possess higher rate capability as compared to full cells comprising Li 1.2 Ni 0.13 Mn 0.54 Co 0.13 O 2 cathodes. Thus, the electrochemical performance of Li 1.2 Ni 0.27 Mn 0.40 Co 0.13 O 2 cathodes in full cells with prelithiated graphite anodes is promising for practical high energy density Li-ion batteries. These results indicate the positive influence of higher Ni content in Li- and Mn-rich cathodes for better electrochemical performance in practical Li-ion batteries.