Application of Electrochemically Formed Polyazulene to Rechargeable Lithium Battery

Abstract

An electrochemically formed polyazulene(PAz), one of the electroconductive polycyclic hydrocarbons, was studied for its electrochemical properties in order to examine the possibility of utilizing it as a cathode active material of rechargeable lithium battery. The electrode kinetics of PAz film electrode, especially the anion doping-undoping process, were investigated mainly with cyclic voltammetry and FFT impedance method. The cyclic voltammetric results of PAz film showed a highly reversible redox process. Cole-Cole plots for PAz electrode obtained by impedance measurement as a function of doping potential were also found to offer an indication that PAz can be an excellent battery material. The charging-discharging property, and the cyclability of a Li/LiC]O4-PC(propylene carbonate)/PAz battery were then studied as a function of the film thickness of PAz cathode. The charging-discharging behavior of Li/LiC104-PC/PAz was also compared with those of Li/LiC104-PC/polypyrrole and Li/LiC104-PC/polyaniline batteries, which had been examined earlier.When compared with Li/LiC104-PC/polypyrrole or Li/LiClO4-PC/polyaniline batteries, a Li/LiC1OJPAz battery showed fairly high and constant discharge voltage (ca. 3.2V), while keeping 100% of coulombic yield. Inspection by SEM showed that the surface condition of PAz film greatly resembled that of polypyrrole, however, a 10 C cm 2 PAz film was prepared with thicker than polypyrrole formed with the same amount of charge of 10 C cm -2.

New Analysis of Electrochemical Impedance Spectroscopy for Lithium-ion Batteries

“…[1][2][3][4][5][6][7][8][9][10][11][12]17,[25][26][27][28] The conventional EIS measured by a frequency response analyzer (FRA) and potentiostat system is a powerful tool to check the state of LIBs (i.e. SOC and SOH).…”

“…[7][8][9][10] At the same time, Professor Su-Moon Park also investigated electroconducting 158 Tetsuya Osaka, Hiroki Nara, Daikichi Mukoyama, and Tokihiko Yokoshima polymers by means of the EIS. 11,12 In addition, Professor Su-Moon Park [13][14][15] and our team 9,16,17 worked in the same field of electroconducting polymers prior to working on the EIS. Thus, Prof. Su-Moon Park and our team encouraged each other in the same field, contributing to the progress of electroconducting polymers and EIS.…”

Electroactive Copolymers with Oligoanilines in the Main Chain via Oxidative Coupling Polymerization

“…[1] In recent years, a wide range of promising applications are found in the fields of light emitting diodes, rechargeable batteries, anti-static coatings, corrosion inhibitors, organic field-effect transistors, photovoltaic cells, lasers and sensors. [2][3][4][5][6][7][8][9] Of these conducting polymers, polyaniline (PANI) has attracted special attention due to its excellent environmental stability, easy synthesis, and reversible acid/base doping/dedoping chemistry. [10][11][12] Thus, PANI offers the promise of a relatively low-cost, conducting polymer that is both stable and processable.…”

Electrochemical Study on Charge‐Discharge Performance of Lithium/Polyazulene Battery

“…Regarding applicability as a battery material, we have already examined and pointed out that electrodeposited PAz films could be a possible cathode material in rechargeable plastic batteries (18).…”

“…An important part of this work was to determine suitable current density and formation charge and to optimize the electrochemical property of PAz film to provide a cathode material in rechargeabte lithium batteries (18 Film preparation.--PAz films were prepared by galvanostatic electropolymerization on Pt substrates at various current density from 0.6 to 1.6 mA cm -2 in 0.1 mol dm -3 LiClO4/PC containing 0.05 mol dm -3 azulene monomer, while monitoring the electrode potential against time. The amount of deposited PAz was controlled by monitoring the charge passed during electropolymerization.…”