Coulombic Capacities of Carbon Cathodes in Lithium-Thionyl Chloride Cells.

摘要

For lithium-thionyl chloride cells utilizing Teflon-bonded carbon cathodes, the attainable energy decreases with decreasing temperature and increasing rate of discharge. The losses correspond largely to decreases in the apparent coulombic capacities of the cathodes. The cathode capacity appears to depend directly on the overall porosity of the electrode rather than on the surface area of the carbon. At room temperature, cathode end-of-life occurs when the clogging of pores with product lithium chloride causes a sharp rise in concentration polarization. The clogging of cathode pores occurs earlier at low temperature, likely due to the precipitation of another reaction product, perhaps sulfur. (Author)