Electrochemical Analyzing Method of the Charge Transfer Reaction at the Interface between Sulfide-based Solid Electrolyte and Positive Electrode Material with Microelectrode

摘要

The charge transfer reaction at the LiNbO_3-coated LiCoO_2/sulfide-based solid electrolyte interface was investigated with a Ni microelectrode. A two-electrode cell was assembled and two electrochemical measurements were performed in order to evaluate exchange currents at various temperatures and activation energy for charge transfer reaction (E_(ct)) for positive electrode material. E_(ct) at the LiNbO_3-coated LiCoO_2 solid electrolyte interface was evaluated to be 48 kJ mol~(-1). This value was smaller than E(CT) at the LiCoO_2/organic electrolyte interface. In case of Li metal negative electrode, it has already found that E_(ct) at the Li metal/solid electrolyte interface is smaller than E_(ct) at the Li metal/organic electrolyte interface due to the lack of a desolvation process. Similar to this, it was demonstrated that the charge transfer reaction at the LiCoO_2/solid electrolyte didn't contain the desolvation process.