Şarj Edilebilir Çinko-Mangan Bataryalarında Mangan Oksit Elektrodun Şarj-Deşarj Performansı Üzerine Elektrolit Etkisinin İncelenmesi

Abstract

In the study, the effects of metal ions (Mn+; Li+, Na+, K+, Cs+, Be2+, Mg2+, Al3+) and Zn2+ ions coming from the anode material in zinc-manganese rechargeable batteries on the electrochemical behavior of MnO2 during charge discharge were examined. Considering that the intercalation and deintercalation of metal ions into the solid electrode structure during charging and discharging of MnO2 is related to their ionic size, in this context, the ionic diameters of metal ions in the gas phase and aqueous solution phase were taken into consideration. The solubility of the active materials to be used in the production of aqueous rechargeable cells and batteries in aqueous solution and their abundance in the earth's crust were taken into consideration in order to eliminate the restrictions in their supply in advanced stages. The basic cathode material of rechargeable zinc manganese batteries is MnO2, and the rechargeability of MnO2 is thought to depend on the pH of the environment and the presence of electroactive or non-electoactive ions in the environment. For this purpose, the electrochemical and charge/discharge behaviors of MnO2 were examined at different pHs and in the presence of the different metal ions mentioned above. In this thesis study, the effect of different electrolyte components on the charge-discharge performance of MnO2 electrode in rechargeable Zinc-Manganese Batteries was investigated using mainly electrochemical techniques. For this purpose, the charge- discharge properties of MnO2 (EMD) electrode coatings formed electrochemically in the anodic region on the graphite electrode in MnSO4 aqueous solutions were examined by constant current charge-discharge tests. Charge-discharge performances of manganese dioxide (MnO2) electrode coatings (EMD) was measured from +1.3 V to -0.2 V in aqueous solutions containing Li2SO4, Na2SO4, K2SO4, CsSO4, BeSO4, MgSO4, Al2(SO4)3, ZnSO4, (NH4)2SO4 and H2SO4 electrolytes. During electrochemical deposition of MnO2; electrochemical behavior of Mn2+ ions in aqueous solution is investigated while it was in solutions containing Na+, Mg2+, Al3+, Zn2+, NH4+ and H3O+ ions using aqueous MnSO4 solutions. Characterization of structural changes of pristine MnO2 (EMD) electrode and charged-discharged MnO2 electrode was carried out by using Electrochemical Impedance Spectroscopy (EIS), XRD and SEM-EDX methods.