Journal of Chemical and Engineering Data, Vol.55, No.5, 1789-1793, 2010
Multichannel Conductivity Measurement Equipment for Efficient Thermal and Conductive Characterization of Nonaqueous Electrolytes and Ionic Liquids for Lithium Ion Batteries
Knowledge of the (specific) conductivities (kappa) of nonaqueous electrolytes and their liquid range are key issues for the development and optimization of lithium ion batteries. Solidification and melting points of ionic liquids (ILs) cannot be determined easily, as ILs show a tendency toward supercooling, especially when high cooling rates are needed to get useful signals. Therefore, we have developed an integrated computer-controlled measurement apparatus that allows the determination of conductivity and solidification or fusion points as functions of temperature simultaneously for up to 30 samples and at very small cooling rates (as low as 1 K.h(-1)). The accuracy of the conductivity measurement equipment was analyzed by the error propagation law and by experiments as well. Over the range 5 mu S.cm(-1) to 5 mS.cm(-1). relative uncertainties of better than 2 % of the measured values were achieved. The relative resolution of the conductivity measurements is better than 0.001 times the measured value. A detailed description of our system, including circuitries and error calculations, is Oven along with some examples of its application in studying liquid electrolyte solutions and ILs.