Computational Design of Microarchitected Flow-Through Electrodes for Energy Storage

TL;DR

This paper introduces a computational approach to design microarchitected flow-through electrodes with spatially varying porosity, leading to improved power efficiency in electrochemical energy storage devices like vanadium redox flow batteries.

Contribution

It develops a novel computational design methodology for creating optimized, architected electrode microstructures with variable porosity for enhanced energy storage performance.

Findings

Architected electrodes outperform uniform porosity electrodes in power efficiency.

Optimized porosity distributions reduce power loss across various operating conditions.

The design approach scales effectively to larger electrode systems.

Abstract

Porous flow-through electrodes are used as the core reactive component across electrochemical technologies. Controlling the fluid flow, species transport, and reactive environment is critical to attaining high performance. However, conventional electrode materials like felts and papers provide few opportunities for precise engineering of the electrode and its microstructure. To address these limitations, architected electrodes composed of unit cells with spatially varying geometry determined via computational optimization are proposed. Resolved simulation is employed to develop a homogenized description of the constituent unit cells. These effective properties serve as inputs to a continuum model for the electrode when used in the negative half cell of a vanadium redox flow battery. Porosity distributions minimizing power loss are then determined via computational design optimization to generate architected porosity electrodes. The architected electrodes are compared to bulk, uniform porosity electrodes and found to lead to increased power efficiency across operating flow rates and currents. The design methodology is further used to generate a scaled-up electrode with comparable power efficiency to the bench-scale systems. The variable porosity architecture and computational design methodology presented here thus offers a novel pathway for automatically generating spatially engineered electrode structures with improved power performance.