A comparative study, of 1 M and 8 M KOH electrolyte concentrations, used in Ni-MH batteries

作者：Khaldi C^*; Mathlouthi H; Lamloumi J

来源：Journal of Alloys and Compounds, 2009, 469(1-2): 464-471.

DOI：10.1016/j.jallcom.2008.01.143

• Chronopotentiometry
• Chronoamperometry
• Cyclic voltammetry
• Electrochemical impedance spectroscopy
• Scanning electron microscopy

One may wonder if we really should use a very high concentration of KOH electrolyte in Ni-MH batteries, to keep the thermodynamic and kinetic properties of the alloy, while this solution is very aggressive to the used alloys. In this work we present a comparative study, using different techniques of two concentrations, 1 M and 8 M KOH electrolytes. The maximum capacity values are 295 mAh g(-1) and 237 mAh g(-1), the loss in capacity, after 23 cycles, are of 10% and 58%, the polarization after the activation are 110 mV and 360 mV and the thickness of the corrosion layer, on the electrode surface, are 7 nm and 42 nm, for the 1 M and 8 M KOH electrolytes, respectively. These results showed that replacing the solution 8 M with 1 M improves the performance of Ni-MH batteries and leads to better results.

• 出版日期2009-2-5