title: Employing Synergetic Effect of Doping and Thin Film Coating to Boost the Performance of Lithium-Ion Battery Cathode Particles.
abstract: Atomic layer deposition (ALD) has evolved as an important technique to coat conformal protective thin films on cathode and anode particles of lithium ion batteries to enhance their electrochemical performance. Coating a conformal, conductive and optimal ultrathin film on cathode particles has significantly increased the capacity retention and cycle life as demonstrated in our previous work. In this work, we have unearthed the synergetic effect of electrochemically active iron oxide films coating and partial doping of iron on LiMn1.5Ni0.5O4 (LMNO) particles. The ionic Fe penetrates into the lattice structure of LMNO during the ALD process. After the structural defects were saturated, the iron started participating in formation of ultrathin oxide films on LMNO particle surface. Owing to the conductive nature of iron oxide films, with an optimal film thickness of ~0.6 nm, the initial capacity improved by ~25% at room temperature and by ~26% at an elevated temperature of 55 °C at a 1C cycling rate. The synergy of doping of LMNO with iron combined with the conductive and protective nature of the optimal iron oxide film led to a high capacity retention (~93% at room temperature and ~91% at 55 °C) even after 1,000 cycles at a 1C cycling rate.
authors.affiliation: Department of Chemical and Biochemical Engineering, Missouri University of Science and Technology, Rolla, Missouri 65409, United States.
authors.forename: Rajankumar L
authors.initials: RL
authors.lastname: Patel
authors.affiliation: TEM Laboratory, University of New Mexico, Albuquerque, New Mexico 87131, United States.
authors.forename: Ying-Bing
authors.initials: YB
authors.lastname: Jiang
authors.affiliation: Department of Chemistry, Missouri University of Science and Technology, Rolla, Missouri 65409, United States.
authors.forename: Amitava
authors.initials: A
authors.lastname: Choudhury
authors.affiliation: Department of Chemical and Biochemical Engineering, Missouri University of Science and Technology, Rolla, Missouri 65409, United States.
authors.forename: Xinhua
authors.initials: X
authors.lastname: Liang