Doctoral Dissertations


Yan Gao

Keywords and Phrases

Atomic Layer Deposition (ALD); Cathode; Coating; Doping; Li-Ion Battery


”Li-ion battery now plays an irreplaceable role in supplying green and convenient energy. In this work, atomic layer deposition (ALD) was used to modify Li-ion battery cathode particles for performance enhancement.

An ultrathin and conductive CeO2 ALD film was deposited on Li-rich layered cathode particles, of which the specific capacity and cyclic stability were significantly improved. On the same cathode particles, FeOx ALD and post-annealing resulted in a stable and conductive surface spinel phase to improve the performance.

Synergetic TiN coating and Ti doping were performed on a LiFePO4 (LFP) cathode and extended its cycle life. The TiN ALD precursor, TiCl4, reacted with the surface of LFP and formed Ti-doped phase during the ALD process.

The modification using FeOx ALD and post-annealing was also carried out on spinel LiMn1.5Ni0.5O4 cathode particles. The parasitic reactions due to high working voltage of this cathode were suppressed by this method, and the intrinsic electronic and ionic conductivities were significantly improved. Moreover, by controlling post-annealing temperature, a porous structure was achieved for the cathode particles, which can further increase the specific capacity and cyclic stability.

A synergetic bi-elemental modification was performed on Ni-rich LiNi0.8Mn0.1Co0.1O2 (NMC811) cathode particles using Zr-surface doping, followed by Al2O3 coating. This rational design derived from individual investigation on Al2O3 and ZrO2 modified NMC811, which proved better performance of Al2O3 as a coating material and Zr as a dopant”--Abstract, page iv.


Liang, Xinhua

Committee Member(s)

Ludlow, Douglas K.
Rownaghi, Ali A.
Wang, Jee-Ching
Park, Jonghyun


Chemical and Biochemical Engineering

Degree Name

Ph. D. in Chemical Engineering


This work was supported in part by the National Science Foundation (NSF DMR 1464111 and NSF CBET 1510085) and the Energy Research and Development Center (ERDC) at Missouri University of Science and Technology.


Missouri University of Science and Technology

Publication Date

Fall 2020

Journal article titles appearing in thesis/dissertation

  • Boosting electrochemical performance of Li1.2Mn0.54Ni0.13Co0.13O2 by atomic layer deposited CeO2 coating
  • Cooperating effects of conformal iron oxide (FeOx) ALD coating and post-annealing on Li-rich layered cathode materials
  • Synergic titanium nitride coating and titanium doping by atomic layer deposition for stable- and high-performance LiFePO4
  • Understanding cation doping achieved by atomic layer deposition for high-performance Li-ion batteries
  • Porous LiMn1.5Ni0.5O4 with tunable Fe doping for high performance Li-ion battery
  • Comprehensive study of Al- and Zr-modified LiNi0.8Mn0.1Co0.1O2 through synergy of coating and doping


xvii, 214 pages

Note about bibliography

Includes bibliographic references.


© 2020 Yan Gao, All rights reserved.

Document Type

Dissertation - Open Access

File Type




Thesis Number

T 11977

Electronic OCLC #