Some factors defining the specific characteristics of a high power Li-SO2 chemical current source have been studied.
The solid-phase product of the cathodic reduction of SO2 passivates the electrode surface, but it is gradually dissolved after de-energizing. Hence, the specific characteristics of the Li-SO2 cell are higher on intermittent than on continuous discharge.
Perchlorate solutions have been compared with bromide solutions. The rate of the cathodic reduction of SO2 is higher in perchlorate solutions. The range of electrochemical stability of the perchlorate solutions is wider and the cathode based on SO2 is rechargeable.
The discharge capacity is higher in acetonitrile solutions as compared with those based on propylene carbonate. In this case the capacity increase is inversely proportional to the viscosity of the solution.
The polarization curve obtained at a porous inert cathode during the reduction of SO2 has areas of intrakinetic, intradiffusion, external kinetic and external diffusion regions.
The anodic behaviour of a lithium electrode is determined by the properties of the film passivating its surface. Polarization resistance at anodic dissolution is practically equal to the ohmic resistance of the film. The electrochemical properties of the film are conditioned by its semiconductive nature.