Fuel cell-The An energy converting device
Fuel cell-An Introduction
Fuel cells are electro-chemical devices. They convert the chemical energy of the fuel into electricity. The energy conversion takes place with high efficiency. The fuel cell consists of an electrolyte and two electrodes. The electrodes are anode and cathode. The electrolyte is in-between the anode and the cathode electrode. Usually the anode and the cathode are porous in nature.As a result, this porous nature of the electrode enhances the gas exchange. Therefore, it improves the chemical reaction. The gas fuels are fed continuously to the electrodes. In other words, the fuel is fed to the anode and the oxidant is fed to the cathode. The electricity produced depends on the flow rate of the fuel and the oxidant.
The current is produced as a result of the electrochemical reaction between fuel and oxidant. The electricity current produced flows out of the fuel cell. The fuel cells are classified into different types. For instants, based on the type of the electrolyte and the field of application. Similarly, the fuel cells can also be categorized not different groups based on the operating temperature. Therefore, the different types are Alkaline fuel cell, Proton exchange membrane, solid oxide, molten carbonate etc. The polymer electrolyte membrane fuel cell is used in automobile. The fuel-cell are main source of electric energy. As a result of high-power density and lower operating temperature, these are best suite for automotive.
Invention of Fuel Cell
Thomas Grubb and Leonard Niedrach invented the PEMFC technology in the early 1960’s. The working of the fuel cell is similar to electrolysis in the opposite sense. For designing a fuel cell its necessary to know the working and construction. Therefore, this blog we discuss about the fuel cell and its working principle. Not only that we will try know some of the fundamentals of the fuel cell. These are necessary for gaining knowledge of the fuel cell.
Construction and Working
For a better understanding of the fuel cell, it’s necessary to know the working. Let us discuss the construction of the fuel cell. The basic principle is the reverse of the electrolysis process. In other words, the hydrogen combines with the oxygen releasing electron. The fuel cell has two electrodes. The positive electrode and the negative electrode. However, the electrodes are thin films that are bonded to the membrane and they are coated with the catalyst. The electrolyte is placed between the two electrodes. In addition, it consists of a catalyst, which enhances the chemical reaction. The oxygen is reduced at the cathode. The hydrogen is oxidized at the anode. The hydrogen breaks (splits). It produces proton and electron. Proton move from anode to cathode through the membrane. Electrons pass through the external circuit. However, the amount of current produced depends on the flow rate of the gases.
The oxygen on the cathode side reacts with proton and an electron. It forms the water and releases the heat. Protons cannot move through the external circuit. Therefore, they can only pass through the membrane. The electrolyte membrane is made of special type of materials. The catalyst present in the anode and cathode don’t take part in a chemical reaction. However, they speed up the electrochemical processes. Catalyst use is mainly the platinum. These are coate over the electrode.
Hydrogen is the main source of fuel for the fuel cell. A variety of energy sources produce the hydrogen. This hydrogen is found everywhere on the earth. In addition, not only that, it can be produced from a number of raw materials. The main source of hydrogen is the water, which is available abundant. However, it is not so easy to use the hydrogen as we think. Though its available abundantly, we need a sustainable hydrogen production method. We consider a number of technical parameters to use hydrogen as a fuel. Like the storing, transportation and distribution of the fuel.
Chemical Reaction of Fuel cell
The chemical reaction involved is in the figure below. The hydrogen is breaks into protons and electron at the anode. At the cathode the oxygen combines with the electron to form water. In the overall reaction the hydrogen reacts with the water to form the water molecule.
All these reactions are possible just because of the proton exchange membrane. This membrane is of a special type material. They are basically the fluorinated Teflon-base material. DuPont produced it for space applications in the 1960s. Therefore, these fluorinated polymers play an important role. Moreover, the soluble polymer improves the utilization of platinum. This soluble form of the polymer has been in use to incorporate the porosity of the carbon support structure. Above all, this increases the interface between, the Electro-catalyst.
Finally, the application of the fuel cell. It can have the use in fulfilling our day to day energy needs. Therefore, let us see some of the application. The main application is in the transportation application. Here it supplies the necessary power to drive the vehicle. It is also in use, in the stationary power production for the domestic applications. Apart from this, it also has application as the backup and portable power sources. In conclusion, the fuel cell is the choice for the future clean energy.
- Fig.1: https://www.hydrogenics.com/technology-resources/hydrogen-technology/fuel-cells/
- Fig.2: https://en.wikipedia.org/wiki/File:Solid_oxide_fuel_cell_protonic.svg
- 3: Rajat
- mirai2: https://4wheelonlineblog.files.wordpress.com/2014/11/mirai2.jpg