The Importance of Interphase Contacts in Li Ion Electrodes: The Meaning of the High-Frequency Impedance Arc

摘要: Li insertion electrodes are made by pressing a mixture of active material and additives on metallic substrate. Here we estimate how various interphase contacts affect the electrode kinetics. We apply variable external mechanical pressure onto different cathodes measure their impedance response. Similar experiments performed dry composites in contact with: Al or Cu foil, Ag paste. Most surprisingly, find that high-frequency arc is due to between metal material. This fundamental contradiction with previous interpretations. propose an equivalent circuit explaining observed phenomena.