High-rate and long-life Li1.18Mn0.56Ni0.13Co0.13O2 cathodes of Li-ion batteries

Li-rich layered oxides, one of the most promising cathodes for high energy Li-ion batteries, commonly undergo some issues such as poor rate performance, low Coulombic efficiency, voltage degradation and so on. In this work, Li1.18Mn0.56Ni0.13Co0.13O2 cathodes with excellent rate capability and cycling stability are prepared by a new molten-salt method using KCl and NaCl as complex flux. The electrochemical tests show that these cathodes can deliver an initial discharge specific capacity of 224.3 mA h g−1 at 300 mA g−1. Meanwhile, the capacity retention ratio remains 92.1% after 100 cycles. The outstanding electrochemical performance is mainly attributed to the uniform distribution of TM-elements in Li1.18Mn0.56Ni0.13Co0.13O2 cathodes, which can promote the electrochemical activation of Li2MnO3-like component. Especially, it is found that the uniformity of TM elements in Li-rich cathodes can be improved by choosing molten-salt method as the synthetic strategy.