Evaluation of Rechargeable Lithium-Copper Chloride Organic Electrolyte Battery System

摘要

The electroformation and discharge of lithium and copper chloride was investigated in half cell and cell configurations in lM LiAlCl4-P.C. The utilization efficiency of lithium in a half-cell depended on the substrate, current density and the loading. In the operation of rechargeable cupric chloride electrodes the tendency of copper salt to form highly soluble chloro cuprate complexes was observed. Impurities present in the solution caused significant self-discharge of the lithium electrode and increased the copper salt solubility. The formation of highly soluble chloro-complexes was a general phenomenon found for other cathodes salts also such as AgCl and PbCl2 in chloride containing electrolytes. This solubility problem affected significantly the Li-CuCl2 cell performance. The transfer of dissolved copper species to the lithium anode by diffusion or migration resulted in the deposition of a copper film on the anode. It was possible to retard the rate of transfer and consequently to improve the 1st discharge of the cell by employing thick separators. At higher current densities passivation of the lithium anode occurred in the cell. The cells were rechargeable but the cycle life was limited due to loss of cathode active material. A course of investigation to effect possible improvements in the cell performance is suggested. (Author)