Topology Optimization for the Full-Cell Design of Porous Electrodes in Electrochemical Energy Storage Devices

TL;DR

This paper presents a density-based topology optimization framework for designing porous electrodes in electrochemical energy storage devices, leading to significantly improved energy storage capacity compared to traditional designs.

Contribution

It introduces a novel optimization approach that considers full cell physics and enables the design of complex, high-performance electrode structures.

Findings

Optimized designs outperform traditional monolithic electrodes in energy storage.

Up to 750% increase in energy storage for slow ionic diffusion scenarios.

3D designs feature complex channels and interlocked structures.

Abstract

In this paper, we introduce a density-based topology optimization framework to design porous electrodes for maximum energy storage. We simulate the full cell with a model that incorporates electronic potential, ionic potential, and electrolyte concentration. The system consists of three materials, namely pure liquid electrolyte and the porous solids of the anode and cathode, for which we determine the optimal placement. We use separate electronic potentials to model each electrode, which allows interdigitated designs. As a result, a penalization is required to ensure that the anode and cathode do not touch, i.e., causing a short circuit. We compare multiple 2D designs generated for different fixed conditions, e.g. material properties. A 3D design with complex channel and interlocked structure is also created. All optimized designs are far superior to the traditional monolithic electrode design with respect to energy storage metrics. We observe up to a 750% increase in energy storage for cases with slow effective ionic diffusion within the porous electrode.