The electrochemical performance of sodium-ion-modified spinel LiMnO used for lithium-ion batteries.

The spinel LiMnO cathode material has been considered as one of the most potential cathode active materials for rechargeable lithium ion batteries. The sodium-doped LiMnO is synthesized by solid-state reaction. The X-ray diffraction analysis reveals that the LiNaMnO (0 ≤ x ≤ 0.01) exhibits a single phase with cubic spinel structure. The particles of the doped samples exhibit better crystallinity and uniform distribution. The diffusion coefficient of the LiNaMnO sample is 2.45 × 10 cm s and 3.74 × 10 cm s, which is much higher than that of the undoped spinel LiMnO sample, indicating the Na-ion doping is favorable to lithium ion migration in the spinel structure. The galvanostatic charge-discharge results show that the Na-ion doping could improve cycling performance and rate capability, which is mainly due to the higher ion diffusion coefficient and more stable spinel structure. [ABSTRACT FROM AUTHOR]