A Study On Performance Of Conductive Polyaniline Used As A Positive Electrode Of Battery

Nowadays, search for environmental friendly, safe new battery materials becomes new need and trend. Polyaniline, which has a reversible redox reaction, is a cheap material and simple to compose. It has good high temperature resistance and oxidation resistance, higher conductivity, good melt processability, and high specific energy (539.2mWh/g). It is environmentally friendly, and has no need to use the process of maintenance .It has outstanding characteristics of many metals unparalleled, and has been developed rapidly as the electrode materials.In this paper, perchloric acid, hydrochloric acid, sulfuric acid are used to dope polyaniline and assembly of polyaniline-zinc battery using zinc as the anode. The influence of concentration of oxidant (NH₄)₂S₂O₈(APS), concentration of conductive addition, the addition of metal ions, pH value of the electrolyte, electrolyte configuration and other factors on the performance of the battery are studied. Polyanniline/carbon(PANi/C) composites with good performance are successfully synthesized.The electrochemical properties of composite materials was studied by constant current charge-discharge test and the micro structure and morphology were studied by XRD test. The best results were shown that using 2 mol/L perchloric as dpoing agent, adjusting the cocentration of aniline and APS to 0.12mol/L and 0.15mol/L separately. Polyaniline, acticarbon and acetylene were better in proportion of 10:2:0.5 by weight. The pH value of the Cl- electrolyte was about 4.0. The maximum of specific capacity for PANi/C-Zn batteries were 93.20mAh/g. After 10 charge-discharge cycles, battery capacity loss was 10.1%. During 10 cycles of charge and discharge coulombic efficiency of batteries can be maintained at between 91.8% 98.6%, which have good cyclic performance.Besides, it was also studied that the influence of metal ions co-doping at 0.05 mol/L with acid on PANi/C battery performance. It is shown that the synthesis of polyaniline dopped by Cu²⁺, Ni²⁺, Mn²⁺ has not improved performance of the cell significantly but made the specific capacity of PANi/C-Zn lost a little. Although there was no increasing in Zn²⁺ doped PANi-Zn battery, it has got a better performance in life of cycling. However, Fe²⁺ caused damage to PANi/C battery badly.