Papers by Author: Yunita Sadeli

Abstract: Polymer electrolyte membrane fuel cell (PEFMC) or also known as proton exchange membrane fuel cell is a chemical conversion device that converts hydrogen and oxygen into electrical energy, heat, and water. One of the most important components of PEMFC is bipolar plate, in which it allows for electrons to flow from the anode to the cathode. The objective of this study was to analyze the effect of the addition of multi walled carbon nanotubes (MWCNT) to increase the mechanical and electrical properties of bipolar plate carbon polymer composite. We utilized graphite waste product from electric arc smelting as reinforcementand carbon black made from coconut husk by pyrolysis process as a filler. Bipolar plates were made by compression moulding method at a pressure of 55 MPa and a temperature of 100 o C for 4 hours. Characterization in this study includes density testing, porosity testing, flexural testing, electrical conductivity testing, and observation of the flexural fracture morphology using FESEM. Based on this study, it showed that the addition of 5 %wt MWCNT yielded optimal properties of the bipolar plate (the density was 1.51 g/cm3, the value of porosity was 1.94 %, the flexural strength was 63.31 MPa, and the electrical conductivity was 2.30 S/cm). In conclusion, adding MWCNT as reinforcement in PEMC bipolar plates could reduce the density and the porosity. Thus, it could improve the electrical conductivity and flexural strength of the bipolar plate carbon polymer composites.

Abstract: Current energy resources derived from fossil fuels thinning, and the issue global warning make the relevant parties that concern about the environment has been trying to find alternative renewable energy. Among the renewable energy options, the fuel cell is one of the many alternatives studied by the researchers in the world. One type of fuel cell that is currently being investigated is the proton exchange membrane fuel cell cel. The utilization of graphite and carbon black waste product is expected to result in light-weight and cost-effective bipolar plates.by using recycle materials. In this paper, we used graphite EAF as reinforcement together with carbon black that comes from the coconut husk pyrolysis process and epoxy resin as a binder. We examined the effects of carbon black loading at 5 %wt and 10 %wt, which influenced by differential pressure applied on compression molding process on density, porosity, flexural strength and electrical conductivity of the resulting polymer carbon composite bipolar plate. Pressure was applied from 30 MPa - 60 MPa in increments of 5 MPa while maintaining constant temperature operation at 70oC for 4 hours. Maximum value of bipolar plate was achieved by 5 %wt CB at application 55 MPa, density of 1.69 g/cm3, the flexural strength was measured to be 48 MPa with the porosity of 0.7%, and electrical conductivity of 1.03 S/cm.We demonstrated that waste product such as graphite EAF and carbon black are a good candidate for manufacturing of polymer carbon composite bipolar plates.

Abstract: Proton electrolyte membrane fuel cells (PEMFC) have near zero carbon dioxide and hazardous pollutant emission. Thus, it is considered as one of energy sources for transportation and other application which can improve environmental performance by decreasing the emission of greenhouse gases and other air pollutant. In accordance with its environmental preservation values, graphite waste product from electric arc furnace (graphite EAF) was chosen as a potential candidate material for bipolar plate for PEMFC. The utilization of graphite waste product is expected to result in light-weight and cost-effective bipolar plates. In this paper, we used graphite EAF as a filler together with carbon black and epoxy resin as a binder. We examined the effects of differential pressure applied on compression molding process on density, porosity, flexural strength and electrical conductivity of the resulting carbon polymer composite bipolar plate. Pressure was applied from 30 MPa - 60 MPa in increments of 5 MPa while maintaining constant temperature operation at 700C for 4 hours. Maximum value of bipolar plate density was achieved at application 55 MPa, of 1.69 g/cm3. At this condition, the flexural strength was measured to be 48 MPa with the porosity of 0.7%, and electrical conductivity of 1.03 S/cm. Taken together, we demonstrated that graphite EAF is a good candidate for the manufacturing of polymer composite bipolar plates.