ISSN 1608-4039 (Print)
ISSN 1680-9505 (Online)


cycling

The effect of surface capacity of positive electrodes on cycle life of lithium-sulfur batteries

The effect of sulfur content in positive electrodes (the surface capacity of sulfur electrodes) on the characteristics (such as the depth of sulfur electrochemical reduction, changes in capacitance and Coulomb efficiency during cycle life) of lithium-sulfur cells with electrolytes based on sulfolane was studied. It was shown that the reason for the capacitance decrease of the lithium-sulfur cells at the early stage of its cycle life is the displacement of sulfur of the porous positive electrode from the rear regions into the front ones.

Degradation Mechanism of Electrodes from Sodium Titanate at Cycling

Degradation of Na2Ti3O7-based electrodes is studied by galvanostatic as well as electrochemical impedance spectroscopy methods. The rate of degradation was shown to decrease from cycle to cycle as the cycling progresses and also as the cycling current increases. It was concluded that the main reason of degradation is the gradual an electrolyte reduction with the formation of insoluble products (SEI).