Layered-Layered-Spinel Cathode Materials Prepared by a High Energy Ball-Milling Process for Lithium-ion Batteries

摘要

In this work, we report the electrochemical properties of 0.5Li(2)MnO(3)center dot 0.25LiNi(0.5)Co(0.2)Mn(0.3)O(2)center dot 0.25Li-Ni0.5Mn1.5O4 and 0.333Li(2)MnO(3)center dot 0.333Li-Ni0.5Co0.2Mn0.3O2 center dot 0.333LiNi(0.5)Mn(1.5)O(4) layered-layered-spinel (L*LS) cathode materials prepared by a high-energy ball-milling process. Our L*LS cathode materials can deliver a large and stable capacity of similar to 200 mAh g(-1) at high voltages up to 4.9 V, and do not show the anomalous capacity increase upon cycling observed in previously reported three-component cathode materials synthesized with different routes. Furthermore, we have performed synchrotron-based in situ X-ray diffraction measurements and found that there are no significant structural distortions during charge/discharge runs. Lastly, we carry out (opt-type) van der Waals-corrected density functional theory (DFT) calculations to explain the enhanced cycle characteristics and reduced phase transformations in our ball-milled L*LS cathode materials. Our simple synthesis method brings a new perspective on the use of the high-power L*LS cathodes in practical devices.