| Popis: |
Deposition and discharge of lithium on an inert (nickel) substrate in 1 M LiClO4/propylene carbonate (PC) has been studied as a function of plating and stripping currrents, cycle number, and electrolyte composition. Water ( A mechanism of loss of efficiency during lithium cycling and also on open circuit stand has been formulated: granules of lithium are encapsulated by an insulating film of PC-lithium reaction products, thus severing electrical contact with the substrate. The additives are postulated to form Li+-conductive films on the deposit, allowing deposition onto the granules, and their growth into larger granules. On open circuit stand, the long-term equilibrium favors the formation of an insoluble insulating (Li-PC) film over the Li+-conductive film. It is suggested that such behavior limits the usefulness of propylene carbonate in secondary lithium batteries. |
