Microwave-Assisted Synthesis of High-Voltage Nanostructured LiMn_1.5Ni_0.5O₄ Spinel: Tuning the Mn³⁺ Content and Electrochemical Performance

The LiMn_1.5Ni_0.5O₄ spinel is an important lithium ion battery cathode material that has continued to receive major research attention because of its high operating voltage (∼4.8 V). This study interrogates the impact of microwave irradiation on the Mn³⁺ concentration and electrochemistry of the LiMn_1.5Ni_0.5O₄ spinel. It is shown that microwave is capable of tuning the Mn³⁺ content of the spinel for enhanced electrochemical performance (high capacity, high capacity retention, excellent rate capability, and fast Li⁺ insertion/extraction kinetics). This finding promises to revolutionize the application of microwave irradiation for improved performance of the LiMn_1.5Ni_0.5O₄ spinel, especially in high rate applications.