Microstructural Analysis of Effective Electrode Conductivity in Molten Salt, Na-ZnCl₂ Batteries

Abstract

Intermediate-temperature molten salt batteries are a promising alternative for grid-scale energy storage with several advantages over existing solutions. The cathode of some of these batteries is composed of a porous matrix of materials containing the metal backbone of the electrode, along with electrolyte components that vary and different locations or as the state of charge of the battery changes. In this work, we aim to analyze the influence of the microstructural properties of the cathodic region at different compositions for a Na-Zn ($\text{ZnCl}_\text{2}$) battery. Synthetic geometric models of the electrode at different compositions are generated and then the effective conductivity is estimated through numerical simulation of the current and potential distribution through the material. At a three-phase composition used by a typical electrode assembly, the effective conductivity is approximately three times larger than the electrolyte electrical conductivity.

Manufacturing Free‐Standing, Porous Metallic Layers with Dynamic Hydrogen Bubble Templating

“…This approach is similar to a work by Omar et al on multi-region threephase conductivity of battery electrodes, where more details on the Open-FOAM solver can be found. [62] During the artificial saturation procedure, the local diffusion coefficient was reduced to 10 −15 when a voxel was saturated with water. The effective diffusivity of the whole structure was found by integrating the diffusive flux over the volume multiplied by the length of the system, divided by the concentration difference from the inlet and outlet.…”

AlCl3-NaCl-ZnCl2 Secondary Electrolyte in Next-Generation ZEBRA (Na-ZnCl2) Battery

“…With this in mind, Lee et al [16] improved the cell performance significantly by using a carbon felt to reduce cathodic resistance. To analyze and optimize the influence of the microstructural properties of the cathodic region at different State of Charges (SOC) of the Na-ZnCl2 battery, Godinez-Brizuela et al [17] developed a synthetic geometric model for the cathodic region for microstructural analysis of its effective conductivity, which could be used to assist the cathode improvement. 2Na + ZnCl ↔ Zn + 2NaCl…”