A Commercial Activated Carbon Powder as a Medium for Electrochemical Hydrogen Storage: An Experimental Investigation on Electrochemical Hydrogen Storage Capacity With Potential Application in Automobiles
Emissions from automobiles running on conventional hydrocarbon-based fossil fuels have lead to increase in concentration of green-house gases (GHGs) that further have contributed in global warming to a great extent. For past few decades hydrogen has emerged as a potential alternative of conventional fossil fuels that could be stored on board and produced domestically and therefore, is globally considered as a future fuel. But, efficient and safe storage and few challenged to be addressed by the researchers. One solution to the problem is electrochemical storage of hydrogen in a porous medium and its utilisation in fuel cell to generate electricity to power the automobile. The presented paper therefore, focuses on determining the electrochemical hydrogen storage capacity of a commercial activated carbon (aC) electrode soaked in acid with potential application in hydrogen fuel cell. The method of fabrication of solid activated carbon electrode is explained in detail. The proton conductivity, double-layer capacitance and electrochemical hydrogen storage capacity of the sample electrode was measured at different levels of hydration. All the testing procedures are discussed and obtained results are used to reach conclusion and recommend future work. The proton conductivity of a fully hydrated commercial aC electrode soaked in 1 mol. sulphuric acid was found to be 0.0110 S/cm, double-layer capacitance as 41.0 F/g, and electrochemical hydrogen capacity as 1.08 wt%. The measured hydrogen capacity is comparable with commercially available metal-hydride based hydrogen storage canisters, lithium-ion and lithium-polymer batteries. The work demonstrates the flow of hydrogen to-and-fro activated carbon electrode soaked in acid that could be used in PEM fuel cell as an integrated hydrogen storage medium and has a potential application in automobiles.
Index Termsó Activated Carbon, Proton Conductivity, Double-Layer Capacitance, Electrochemical Hydrogen Storage.