119th General Meeting of the KCS

Type Poster Presentation
Area 물리화학
Room No. 포스터발표장
Time 4월 20일 (목요일) 11:00~12:30
Code PHYS.P-22
Subject Computational Materials Science for Lithium Ion Battery Materials: Understanding the Degradation Mechanisms of LiNi1/3Co1/3Mn1/3O2
Authors 이치호, 전병선, 이상욱*
한양대학교 바이오나노공학과, Korea
Abstract Higher energy density combined with longer cycle life is one of the key requirements that need to be addressed in the Li ion batteries applications. Currently, layered Li transition metal oxides were adopted as a power sources for EV and PHEV applications due to their high theoretical capacity and cycling stability. However, accelerated capacity fading still occurs even at the most stable LiNi1/3Co1/3Mn1/3O2 (NCM111). A variety of approaches are being made to find the essential factors affecting the cycling performance. Phase transformation in corporation with a displacement of Li ions from Li layers is known to the crucial features inhibiting the life characteristics of cathode materials, although the mechanisms that drive such evolution at atomic level remain elusive. Here, we present an investigation of chemical and structural evolution induced by Ni migration, and which is the fundamental degradation mechanism of NCM based layered structure cathode materials. This phenomenon was firmly established by combined atom probe tomography (APT) and high-resolution transmission electron microscopy (HR-TEM) analysis. Density functional theory (DFT) calculation was conducted to evaluate the diffusion kinetics of Ni cations within the layered structure and to propose the addition of dopant to suppress the Ni migration.
E-mail holee@cms.hanyang.ac.kr