Lithium solid electrolyte, primary operation temperature

Li2S204 being the SEI component at the Li anode and the solid discharge product at the carbon cathode. The Li—SOCI2 and Li—SO2 systems have excellent operational characteristics in a temperature range from —40 to 60 °C (SOCI2) or 80 °C (SO2). Typical applications are military, security, transponder, and car electronics. Primary lithium cells have also various medical uses. The lithium—silver—vanadium oxide system finds application in heart defibrillators. The lithium—iodine system with a lithium iodide solid electrolyte is the preferred pacemaker cell. 

Primary batteries have existed for over 100 years, but up to 1940, the zinc-carbon battery was the only one in wide use. During World War II and the postwar period, significant advances were made, not only with the zinc-carbon system, but with new and superior types of batteries. Capacity was improved from less than 50 Wh/kg with the early zinc-carbon batteries to more than 400 Wh/kg now obtained with lithium batteries. The shelf life of batteries at the time of World War n was limited to about 1 year when stored at moderate temperatures the shelf life of present-day conventional batteries is from 2 to 5 years. The shelf life of the newer lithium batteries is as high as 10 years, with a capability of storage at temperatures as high as 70°C. Low-temperature operation has been extended from 0 to -40C, and the power density has been improved manyfold. Special low-drain batteries using a solid electrolyte have shelf lives in excess of 20 years. 

Current research is attempting to develop a portable equipment battery that operates not at its normal operating temperature of 120°C but at room temperature. (polyethylene oxide)9LiCF3SOj electrolytes hold such promise. The y-alumina—lithium fluoride primary solid state battery has some applications in the cardiac pacemaker field. 

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