Effect of polysulfide-containing electrolyte on the film formation of the negative electrode

Abstract The improvement of cycling behaviour and self discharge of lithium—carbon intercalation electrodes as well as metallic lithium electrodes in polysulfide-containing propylene carbonate-based electrolyte is demonstrated. Cyclic voltammetry of LiC n electrodes indicates a more complex reductive behaviour only during the first charge/discharge cycle than in an additive-free electrolyte. The products of the polysulfide reduction seem to improve the properties and the quality of the film that is also produced in the absence of S x 2− and promotes its formation on Li or LiC n , respectively. The improvement may be related to thinner polymer—electrolyte interface layers (PEI layers) and/or a larger amount of insulated inorganic compounds in the PEI layers.