Perpustakaan Digital ITB

Indonesia struggles to provide energy supply evenly across the nation due to the uneven electricity demand and difficulty in electricity distribution. Battery is a convenient device to convert chemical energy into electricity. Secondary zinc-air battery, in particular, has gathered tremendous interests due to high theoretical energy density, working voltage, operation safety, and economy viability. However, the common problem faced by the zinc-air battery circulates around the inefficiency of air catalysts and poor energy efficiency. This research is aimed to determine the effect of Graphene:CNT ratio utilized as the cathode and relative humidity of Bandung towards the performance of secondary zinc-air battery. The research was conducted by varying the ratio of Graphene:CNT cathode composition: 100% Graphene, 50:50 Graphene:CNT, and 100% CNT. The variation of relative humidity of Bandung tested were 70% and 80%. Battery assembled was tested through electrochemical characterization tests, which are through the Cyclic Voltammetry (CV) test, Potentiodynamic test, and Electrochemical Impedance Spectroscopy (EIS) test. Mathematical modelling using MATLAB software was prepared to validate the experiment data. Battery with 100% CNT cathode composition produced the highest capacitance and lowest resistance when tested at 70% RH. 100% Graphene produced the highest power density of 0.28 mW/cm2 at 2.47 mA/cm2. Batteries tested at 70% RH produced the best performance since cathode experienced excessive wetting at higher relative humidity. Mathematical modelling proved experimental results were valid, although producing large discrepancy due to assumptions made in the simulation.