Imidazolium ionic liquids as electrolytes for manganese dioxide free Leclanché batteries

• Published in: Applied energy 2009-09, Vol.86 (9), p.1512-1516
• Main Authors: Stracke, M.P., Migliorini, M.V., Lissner, E., Schrekker, H.S., Dupont, J., Gonçalves, R.S.
• Format: Article
• Language: English
• Subjects: Applied sciences; Benzoquinone reduction; Direct energy conversion and energy accumulation; Electrical engineering. Electrical power engineering; Electrical power engineering; Electrochemical conversion: primary and secondary batteries, fuel cells; Energy accumulation; Energy storage; Energy storage Environmental impact Energy technology Leclanche battery Imidazolium ionic liquid electrolytes Benzoquinone reduction; Energy technology; Environmental impact; Exact sciences and technology; Imidazolium ionic liquid electrolytes; Leclanché battery
• ISSN: 0306-2619; 1872-9118
• DOI: 10.1016/j.apenergy.2008.11.014

A set of four imidazolium ionic liquids (solid at room temperature) and one imidazolium ionic solid was screened for its potential as electrolytes in manganese dioxide free Leclanché batteries, equipped with a zinc anode and graphite cathode. Electrical impedance spectroscopy allowed to determine the room-temperature ionic solids (RTISs) ionic conductivities, which was the highest for carboxylic acid functionalized RTIS 3 [C 2O 2MIm][Cl]. The toxic manganese dioxide was substituted by benzoquinone. A systematic ionic conductivity optimization of RTIS 3–benzoquinone–ZnSO 4–H 2O mixtures at room temperature resulted in the identification of the following conditions for the Leclanché battery studies: 50 mg of a 50:50 RTIS:benzoquinone mixture and 96 mg of water. The chronopotentiometric experiments with a constant current of 5 μA showed a remarkable performance for the RTIS 3 based battery. The potential (1.47 V) and stability is comparable to that of the commercial Rayovac ® battery filling (model AA). Furthermore, linear potentiodynamic voltammetry (0.01 V/s) and chronoamperometric analysis at short-circuit conditions (0.0 V) validated the RTIS 3–benzoquinone–water battery as a promising alternative for manganese dioxide free Leclanché batteries.