Artificial cathode electrolyte interphase for improving high voltage cycling stability of thick electrode with Co-free 5 V spinel oxides

Li, Weikang; Cheng, Diyi; Shimizu, Ryosuke; Li, Yixuan; Yao, Weiliang; Raghavendran, Ganesh; Zhang, Minghao; Meng, Ying Shirley

doi:10.1016/j.ensm.2022.04.002

DOE OSTI · 1969521

Artificial cathode electrolyte interphase for improving high voltage cycling stability of thick electrode with Co-free 5 V spinel oxides

Li, Weikang·Cheng, Diyi·Shimizu, Ryosuke·Li, Yixuan·Yao, Weiliang·Raghavendran, Ganesh·Zhang, Minghao·Meng, Ying Shirley

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Abstract

Spinel-type cathode LiNi 0.5 Mn 1.5 O 4 (LNMO) has intrigued the transportation industry due to its high operating voltage and total elimination of the expensive cobalt element. However, LNMO cathode with high mass loading (> 3 mAh/cm 2 in areal capacity) has suffered from excessive capacity degradation upon long cycling. Here, a robust Al 2 O 3 surface layer is introduced to the thick LNMO electrode via atomic layer deposition (ALD). The capacity retention in full cells with the graphite anode is improved from 46.3% to 75.3% after 300 cycles with cutoff voltage up to 4.85 V, while enabling average Coulombic efficiency of 99.9% during the cycling. The post-mortem analyses reveal that the Al 2 O 3 surface layer would convert to Al-O-F /Al-F species upon cycling, offering stable interphase to protect the cathode material. Furthermore, these results demonstrate the significance of surface modification enabling high voltage cathode for next-generation LIBs.

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BibTeX RIS

Li, Weikang, Cheng, Diyi, Shimizu, Ryosuke, Li, Yixuan, Yao, Weiliang, Raghavendran, Ganesh, Zhang, Minghao, Meng, Ying Shirley. 2022-04-04. Artificial cathode electrolyte interphase for improving high voltage cycling stability of thick electrode with Co-free 5 V spinel oxides. https://doi.org/10.1016/j.ensm.2022.04.002

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