Electrolytes For Magnesium Batteries Research Articles

Conductivity of low-temperature electrolytes for magnesium batteries

Specific conductivities have been determined for MgCl 2, MgBr 2, Mg(ClO 4) 2, 2 M Mg(ClO 4) 2 + x M MgCl 2, and 2 M Mg(ClO 4) 2 + x M Mgbr 2 (where x = 0.1 to 2 M) in pure water over the concentration range 0.1 to 3 M at +20, +10, 0, −10 and −20 °C. The conductivities increase in the order MgBr 2 > MgCl 2 > Mg(ClO 4) 2. Conductance maxima have been evaluated and the values of the ‘a’ and ‘b’ constants of Casteel-Amis equation have been obtained. A comparative study with the available literature data for MgCl 2 has been undertaken. Cells comprising Mg/electrolyte/ m-dinitrobenzene (1 V; 3 A h) have been fabricated and tested at +20 and −20 °C using the maximum conductivity of the different electrolytes. Mixed electrolytes have also been investigated. From the observed discharge behaviour, 2.0 M Mg(ClO 4) 2 appears to be the most promising electrolyte solution for practical magnesium batteries that are required to operate over a wide temperature range.