Effect of Co Content on the Electrochemical Properties of (MgCoNiZnLi)O Based High Entropy Oxides for Li-Ion Batteries

Abstract

High entropy oxides (HEOs) are attractive as a negative electrode material for lithium-ion batteries (LIBs), because of the high specific capacities and cycling stabilities. Moreover, they offer a wide range of compositional variation to reach the desired electrochemical performances. In this study, we synthesized the Co5(MgNiZnLi)95O and Co35(MgNiZnLi)65O high entropy oxides using conventional solid state reaction technique and examined their electrochemical properties in lithium-ion cells as anode material. The structural properties of as-synthesized high entropy oxides were investigated using X-ray diffraction (XRD) technique, which showed that all the oxides have single-phase rock-salt structure. The increase in the Co content from 5% to 35%, the high entropy oxide based anodes resulted in improved discharge capacity due to the different oxidation states in Co ions. This work indicates that the compositional and elemental valences are very crucial to design and achieve novel high performance high entropy oxide based anode materials for lithium-ion batteries.

Keywords

• Conversion type anode
• Li-ion battery
• High entropy oxide

References

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