Cooling Induced Surface Reconstruction during Synthesis of High-Ni Layered Oxides

Ming Jian Zhang, Xiaobing Hu, Maofan Li, Yandong Duan, Luyi Yang, Chong Yin, Mingyuan Ge, Xianghui Xiao, Wah Keat Lee, Jun Young Peter Ko, Khalil Amine, Zonghai Chen, Yimei Zhu, Eric Dooryhee, Jianming Bai*, Feng Pan, Feng Wang

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

7 Scopus citations

Abstract

Transition metal layered oxides have been the dominant cathodes in lithium-ion batteries, and among them, high-Ni ones (LiNixMnyCozO2; x ≥ 0.7) with greatly boosted capacity and reduced cost are of particular interest for large-scale applications. The high Ni loading, on the other hand, raises the critical issues of surface instability and poor rate performance. The rational design of synthesis leading to layered LiNi0.7Mn0.15Co0.15O2 with greatly enhanced rate capability is demonstrated, by implementing a quenching process alternative to the general slow cooling. In situ synchrotron X-ray diffraction, coupled with surface analysis, is applied to studies of the synthesis process, revealing cooling-induced surface reconstruction involving Li2CO3 accumulation, formation of a Li-deficient layer and Ni reduction at the particle surface. The reconstruction process occurs predominantly at high temperatures (above 350 °C) and is highly cooling-rate dependent, implying that surface reconstruction can be suppressed through synthetic control, i.e., quenching to improve the surface stability and rate performance of the synthesized materials. These findings may provide guidance to rational synthesis of high-Ni cathode materials.

Original languageEnglish (US)
Article number1901915
JournalAdvanced Energy Materials
Volume9
Issue number43
DOIs
StatePublished - Nov 1 2019

Keywords

  • high-Ni layered oxide cathodes
  • lithium-ion batteries
  • quenching
  • solid-state synthesis
  • surface reconstruction

ASJC Scopus subject areas

  • Renewable Energy, Sustainability and the Environment
  • Materials Science(all)

Fingerprint Dive into the research topics of 'Cooling Induced Surface Reconstruction during Synthesis of High-Ni Layered Oxides'. Together they form a unique fingerprint.

Cite this