Effects of current distribution on mass transport in the positive electrode of a liquid metal battery

TL;DR

This study investigates how current distribution affects mass transport and flow in the positive electrode of a Li||Bi liquid metal battery, revealing that non-uniform currents induce convection impacting cell performance.

Contribution

It provides the first numerical analysis linking current distribution to compositional convection in the positive electrode of a liquid metal battery.

Findings

Non-uniform current distribution induces compositional convection.

Convection influences flow patterns and cell performance.

Numerical results highlight the coupling between charge transfer and mass transport.

Abstract

Liquid metal electrodes are one of the key components of different electrical energy storage technologies. The understanding of transport phenomena in liquid electrodes is mandatory in order to ensure efficient operation. In the present study we focus our attention on the positive electrode of the Li||Bi liquid metal battery. Starting from a real experimental setup, we numerically investigate the charge transfer in a molten salt electrolyte and the mass transport in the positive electrode. The two phenomena are tightly coupled, because the current distribution influences the concentration field in the positive electrode. The cell is studied during charging when compositional convection becomes apparent. First results of compositional convection from a non-uniform current distribution are presented, highlighting its capability to affect the flow in the positive electrode and the cell performance.