title: Temperature-Dependent Lithium-Ion Diffusion and Activation Energy of Li1.2Co0.13Ni0.13Mn0.54O2Thin-Film Cathode at Nanoscale by Using Electrochemical Strain Microscopy.
abstract: This paper presents the in situ mapping of temperature-dependent lithium-ion diffusion at the nanometer level in thin film Li1.2Co0.13Ni0.13Mn0.54O2cathode using electrochemical strain microscopy. The thin-film Li1.2Co0.13Ni0.13Mn0.54O2cathode exhibits higher lithium-ion diffusivities with increasing temperature, which explains the higher capacity observed in the lithium-ion batteries with a Li-rich cathode at elevated temperature. In addition, the activation energy for lithium-ion diffusion can be extracted in an Arrhenius-type plot at the level of grain structure with the assumption that the ionic movement is diffusion controlled. Compared with the grain interiors, the grain boundaries show relatively lower activation energy; hence, it is the preferred diffusion path for lithium ions. This study has bridged the gap between atomistic calculations and traditional macroscopic experiments, showing direct evidence as well as mechanisms for ionic diffusion for Li-rich cathode material.
authors.affiliation: Department of Mechanical Engineering, National University of Singapore , 9 Engineering Drive 1, Singapore 117576.
authors.forename: Shan
authors.initials: S
authors.lastname: Yang
authors.affiliation: Department of Mechanical Engineering, National University of Singapore , 9 Engineering Drive 1, Singapore 117576.
authors.forename: Binggong
authors.initials: B
authors.lastname: Yan
authors.affiliation: Department of Mechanical Engineering, National University of Singapore , 9 Engineering Drive 1, Singapore 117576.
authors.forename: Jiaxiong
authors.initials: J
authors.lastname: Wu
authors.affiliation: Department of Mechanical Engineering, National University of Singapore , 9 Engineering Drive 1, Singapore 117576.
authors.forename: Li
authors.initials: L
authors.lastname: Lu
authors.affiliation: Department of Mechanical Engineering, National University of Singapore , 9 Engineering Drive 1, Singapore 117576.
authors.forename: Kaiyang
authors.identifier: http://orcid.org/0000-0002-3348-0018
authors.initials: K
authors.lastname: Zeng
keywords: ESM; Li1.2Co0.13Ni0.13Mn0.54O2 cathode material; activation energy; diffusion coefficient; lithium-ion batteries; temperature dependence