Transfer processes at phase boundaries between liquid and solid electrolytes

For post-lithium-ion batteries, such as lithium–sulfur or lithium–air cells, it is advantageous to spatially separate the cathode and the anode using a solid electrolyte. This means that electrolytes specifically tailored to the electrochemical conditions of the individual electrodes can be used without them mixing. In addition, internal short circuits caused by dendrite growth can be prevented.

However, the implementation of a solid electrolyte requires new phase boundaries, which increase the total resistance of the cell and consequently reduce the potential. The charge transfer resistance at the solid–liquid interface depends on various factors such as the materials used, the concentration of the liquid electrolyte, and the temperature.

To explore the charge transfer kinetics at a solid–liquid interface, a special electrochemical cell was designed to measure the potential drop. Various electrochemical measurement methods, such as DC polarization measurements or impedance spectroscopy, are used to characterize the properties.

[1] Schleutker, M.; Bahner, J.; Tsai, C.; Stolten, D.; Korte, C. Phys. Chem. Chem. Phys. 2017, https://dx.doi.org/10.1039/C7CP05213H.