Towards improved structural stability and electrochemical properties of a Li-rich material by a strategy of double gradient surface modification

被引：59

作者：

Ding, Xiang ^{[1
,2
]}

Li, Yi-Xuan ^{[1
,2
]}

Wang, Shuo ^{[1
,2
]}

Dong, Jie-Min ^{[1
,2
]}

Yasmin, Aqsa ^{[1
,2
]}

Hu, Qiao ^{[1
,2
]}

Wen, Zhao-Yin ^{[3
]}

Chen, Chun-Hua ^{[1
,2
]}

机构：

[1] Univ Sci & Technol China, CAS Key Lab Mat Energy Convers, Dept Mat Sci & Engn, Hefei 230026, Anhui, Peoples R China

[2] Univ Sci & Technol China, Collaborat Innovat Ctr Suzhou Nano Sci & Technol, Hefei 230026, Anhui, Peoples R China

[3] Chinese Acad Sci, Shanghai Inst Ceram, Key Lab Energy Convers Lab, Shanghai 200050, Peoples R China

来源：

NANO ENERGY | 2019年 / 61卷

基金：

美国国家科学基金会; 国家重点研发计划;

关键词：

Li-rich cathode; Sodium fluoride; Double gradient; Interface; Long-cycle life; LAYERED CATHODE MATERIALS; LITHIUM-ION BATTERIES; COMPOSITE CATHODE; CYCLING STABILITY; PERFORMANCE; OXIDES; LI1.2NI0.13CO0.13MN0.54O2; LI1.2MN0.54CO0.13NI0.13O2; DEGRADATION;

D O I：

10.1016/j.nanoen.2019.04.078

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

The electrochemical properties of layered Li-rich oxide Li1.2Ni0.13Co0.13Mn0.54O2 (LLO) can be enhanced by a facile NaF surface modification. We have clarified by XPS, HR-TEM and HAADF-STEM analyses that the mechanism is the formations of a gradient coating layer Na1-xLixF and a gradient LLO surface Li1.2-xNaxNi0.13Co0.13Mn0.54O2 via a Li+/Na+ exchange reaction. The exchange reaction occurs at the Li-slabs of LLO down to a depth of less than 15 nm. After such a double gradient surface modification, the LLO displays markedly improved cycle life and rate capability as well as suppressed voltage decay. It exhibits a capacity retention of 85% beyond 1000 cycles at 10 C and a voltage decay of only 0.0021 V per cycle at 0.5 C, revealing great application prospects in energy storage materials.

引用

页码：411 / 419

页数：9

共 49 条

[11] Formation, dynamics, and implication of solid electrolyte interphase in high voltage reversible conversion fluoride nanocomposites [J].