A treatment of particle-electrolyte sharp interface fracture in solid-state batteries with multi-field discontinuities

TL;DR

This paper introduces a computational framework using discontinuous finite element methods to model particle-electrolyte interface fracture and electro-chemo-mechanics in solid-state batteries, accommodating complex geometries and interfacial discontinuities.

Contribution

It extends finite element methods for sharp interface treatment in solid-state batteries, capturing fracture and interfacial phenomena without conformal meshing.

Findings

Framework effectively models interfacial fracture and electro-chemo-mechanics.

Flexible to arbitrary particle shapes and geometries.

Demonstrated on micro-structures of solid-state batteries.

Abstract

In this work, we present a computational framework for coupled electro-chemo-(nonlinear) mechanics at the particle scale for solid-state batteries. The framework accounts for interfacial fracture between the active particles and solid electrolyte due to intercalation stresses. We extend discontinuous finite element methods for a sharp interface treatment of discontinuities in concentrations, fluxes, electric fields and in displacements, the latter arising from active particle-solid electrolyte interface fracture. We model the degradation in the charge transfer process that results from the loss of contact due to fracture at the electrolyte-active particle interfaces. Additionally, we account for the stress-dependent kinetics that can influence the charge transfer reactions and solid state diffusion. The discontinuous finite element approach does not require a conformal mesh. This offers the flexibility to construct arbitrary particle shapes and geometries that are based on design, or are obtained from microscopy images. The finite element mesh, however, can remain Cartesian, and independent of the particle geometries. We demonstrate this computational framework on micro-structures that are representative of solid-sate batteries with single and multiple anode and cathode particles.