Polymeric electrolytes for ambient temperature lithium batteries

Polyacetylene can be electrochemically oxidized in a cell of the type, Li/LiX in propylene carbonate/CH sub x, with nearly 100% coulombic efficiency for doping levels (y in (ClO4) sub y sub x), of less than 0.10. At higher values, the electrochemical potential of the oxidized film is above 3.9 V vs. Li/Li(+), and the electrolyte is unstable. Reduced polyacetylene (Li sub y CH) sub x can serve as an anode in a non-aqueous electrolyte is unstable. Reduced polyacetylene (Li sub y CH) sub x can serve as an anode in a non-aqueous electrolyte battery in the traditional role of lithium. However, stable voltages and high coulombic efficiency for the reduction/oxidation process in an electrolyte of LiClO4 in tetrahydrofuran are only observed at reduction levels of about 0.10. In addition, the potential of a polyacetylene anode doped with Li(+) is 0.5 to 1.5 V positive to that of Li in the same solution. At present, polyacetylene electrodes are rather unstable, sensitive to impurities, and characterized by low volumetric energy density, and low-moderate gravimetric energy density. They do not appear to offer major advantages for use in high energy density, rechargeable, non-aqueous electrochemical cells.