Role of Lithium Doping in P2-Na0.67Ni0.33Mn0.67O2for Sodium-Ion Batteries

Yingying Xie, Eric Gabriel, Longlong Fan, Inhui Hwang, Xiang Li, Haoyu Zhu, Yang Ren, Chengjun Sun, Julie Pipkin, Malia Dustin, Matthew Li, Zonghai Chen, Eungje Lee, Hui Xiong

Research output: Contribution to journalArticlepeer-review

81 Scopus citations

Abstract

P2-structured Na0.67Ni0.33Mn0.67O2 (PNNMO) is a promising Na-ion battery cathode material, but its rapid capacity decay during cycling remains a hurdle. Li doping in layered transition-metal oxide (TMO) cathode materials is known to enhance their electrochemical properties. Nevertheless, the influence of Li at different locations in the structure has not been investigated. Here, the crystallographic role and electrochemical impact of lithium on different sites in PNNMO is investigated in LixNa0.67-yNi0.33Mn0.67O2+ (0.00 ≤ x ≤ 0.2, y = 0, 0.1). Lithium occupancy on prismatic Na sites is promoted in Na-deficient (Na < 0.67) PNNMO, evidenced by ex situ and operando synchrotron X-ray diffraction, X-ray absorption spectroscopy, and 7Li solid-state nuclear magnetic resonance. Partial substitution of Na with Li leads to enhanced stability and slightly increased specific capacity compared to PNNMO. In contrast, when lithium is located primarily on octahedral TM sites, capacity is increased but at the cost of stability.

Original languageEnglish
Pages (from-to)4445-4455
Number of pages11
JournalChemistry of Materials
Volume33
Issue number12
DOIs
StatePublished - 22 Jun 2021

Fingerprint

Dive into the research topics of 'Role of Lithium Doping in P2-Na0.67Ni0.33Mn0.67O2for Sodium-Ion Batteries'. Together they form a unique fingerprint.

Cite this