lithium electrode

The effect of lithium polysulphides on the cyclic deposition/and dissolution of lithium metal on an inert stainless steel electrode and on a lithium metal electrode in sulfolane solutions has been studied. It has been shown that the addition of lithium polysulphides to sulfolane solutions leads to a significant increase in the cycle life (2 or more times) and cycling efficiency of a lithium metal electrode and a lithium metal on inert stainless steel electrode. It also results in the reduction of the corrosion rate of the lithium cathodic deposits.

The analysis of electrochemical impedance of lithium-sulfur cells is complicated by the complexity of the processes occurring inside them. Both electrochemical processes and mass transport processes simultaneously occur on the lithium and sulfur electrodes of the cells, as well as in the bulk electrolyte. A comparative analysis of the distribution functions of relaxation times of symmetric Li||Li, S||Sand and the full lithium-sulfur cell has been conducted.

By the method of the electrochemical noises the processes occurring on the lithium electrodes in an apiotic electrolyte in a steady state as well as at cathodic and anodic polarization have been studied. The processes at electrode polarization were shown to be localized under the passivating surface film. The increase of cathodic current results in the local film interruption and enhancing of the electrochemical noises.

The effect of carbon dioxide on the cycling efficiency of a lithium electrode in triflate electrolyte is studied. Reversible cycling of lithium in that electrolyte is shown to be possible provided the presence of a protecting film on lithium surface. Such a film forms precisely in the presence of carbon dioxide. It was found that the effect of СO₂ on the properties and composition of the protective film has reversible nature.