The electrochemical intercalation reaction of lithium in polymer with conjugated double bonds - III. The electrochemical intercalation reaction of lithium in polynaphthalene

Naphthalene has been polymerized under mild conditions in o-dichlorobenzene with ferric chloride as catalyst. The resulting product polynaphthalene, a nnealed at 650 degrees C in vacuo, is a conducting polymer with conjugated double bonds. A mechanism of the electrochemical intercalation reaction is suggested for the discharge of a Li-polynaphthalene battery on the basis of experimental data obtained from the X-ray analysis, the electron paramagne tic resonance spectrometry etc. The lithium exists in the lithiated compoun d in both atomic and ionic state. The electrochemical intercalation reactio n of lithium enhanced ESR absorption of the intercalation compound (LixC10H 6)(n) has been observed. The diffusion coefficient of Li+ in the intercalat ion compound was measured to be 10(-11) similar to 10(-13) cm(2). s(-1) by the potential step method at room temperature. The electronic conductivity was measured by Hebb-Wagner DC polarization technique, which was five to si x orders of magnitude larger than the ionic one, so the intercalation compo und was a mixed conductor in which the electronic conduction was predominan t.