Modeling of effective cationic transference number in soft matter battery electrolytes based on conservative ensemble theory

High cationic transference numbers are crucial for battery electrolytes, as they prevent ion concentration gradients, which negatively influence battery rate performance. While ionic conductivity reflects the total mobility, concentration, and charge of species, the effective cationic transference, t +,eff , describes the ratio of relevant cation transport relative to the transport of all species. Based on the concept of conservative ensembles and semi-blocking electrodes, we follow a mathematical model to numerically calculate and visualize the conductivity-dependent t +,eff in a system containing solvated ions, ion pairs and ion triplets. We again find that ion association cannot be considered generally detrimental for transport, and showcase several situations in which it leads to high effective cationic transference numbers.