On the Origin of the Extra Electrochemical Capacity Displayed by MO/Li Cells at Low Potential

and thegrowth of a polymer/gel-like film at high and low potentials, respectively, is extremely sensitive to cycling voltage ranges with thebest results obtained when the cells are fully discharged. The low-voltage process is quite reversible over the 0.02 to 1.8 V rangewith a sustained capacity of about 150 mAh/g over a few hundred cycles. Within such a range of potential the polymer/gel-like isbarely evolving while it vanishes as the oxidation potential is increased above 2 V. From the cyclic-voltammogram profiles weconclude that the origin of the low-voltage capacity is nested in the pseudocapacitive character of thein situ made polymeric/gelfilm. Tentative explanations based on comparisons with existing literature are made to explain such an unusual finding.© 2002 The Electrochemical Society. @DOI: 10.1149/1.1467947# All rights reserved.Manuscript submitted July 2, 2001; revised manuscript received November 14, 2001. Available electronically April 2, 2002.

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