Issue 42, 2018

Mechanistic understanding of intergranular cracking in NCM cathode material: mesoscale simulation with three-dimensional microstructure

Abstract

Intergranular cracking in the agglomerated form of secondary particles has been regarded as a major cause for mechanical degradation in layered oxide cathode materials for Li-ion batteries, but its detailed mechanistic origin linked to the mechanical properties of these materials is still unknown. In this study, a mesoscale simulation based on the description of the interaction between primary particles is established by combining the model of the shifted-force Lennard-Jones potential and granular Hertzian model to construct the microstructure of secondary particles of cathode materials. The optimized parameters for each model are developed to compute the mechanical properties based on the response from nano-indentation and uniaxial tensile tests. Furthermore, the adhesion between the primary particles is modified to examine their sensitivity to different modes of deformations. The results show that under tension, an increase in adhesion can significantly strengthen the structure along with increase in brittleness, whereas the response from the localized compression (nano-indentation) is shown to be much less sensitive. In addition, the structural changes during repeated volume expansion/contraction induced from electrochemical cycling are investigated. The results indicate that enhancing particle adhesion can prevent the propagation of intergranular cracking.

Graphical abstract: Mechanistic understanding of intergranular cracking in NCM cathode material: mesoscale simulation with three-dimensional microstructure

Supplementary files

Article information

Article type
Paper
Submitted
02 Aug 2018
Accepted
04 Oct 2018
First published
04 Oct 2018

Phys. Chem. Chem. Phys., 2018,20, 27115-27124

Mechanistic understanding of intergranular cracking in NCM cathode material: mesoscale simulation with three-dimensional microstructure

K. Min and E. Cho, Phys. Chem. Chem. Phys., 2018, 20, 27115 DOI: 10.1039/C8CP04927K

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements