Improvement of electrochemical performance of spherical spinel LiMn₂O₄ cathode material coated with Al-doped ZnO (AZO) for Li-ion battery

In this work, spherical spinel LiMn₂O₄ cathode material has been synthesized successfully. Al-doped ZnO (AZO) materials were coated on the surface of spherical spinel LiMn₂O₄ cathode by a simple wet chemical method. The amount of the AZO coating materials was 0.0 wt%, 0.5 wt%, 1.0 wt%, and 2.0 wt%, respectively. On the surface, the AZO coating could work as an artificial barrier and Li⁺ conductor, inhibiting Mn dissolution and promoting lithium ion migration. The research results show that the electrochemical properties of the modified LiMn₂O₄ materials were improved. The LiMn₂O₄ sample coated with 1 wt% AZO demonstrated the best cycle and rate performances, with capacity retention of 96.5% and 88.8% after 100 cycles at 1 C, 25 °C and 55 °C, respectively, and still possessed the discharge specific capacity of 113.9 mAh g⁻¹ at 5 C, 25 °C. It could be concluded that AZO-modified LiMn₂O₄ material is a viable cathode material for lithium ion batteries.