Some of the greatest devices invented so far draw their power from something so tiny in comparison to them. It thus becomes hard to comprehend the entire technology in one go. One such invention is that of the cells and batteries. We have already studied about the cells in general. However, here we talk about fuel cells in particular.
A fuel cell is a tiny device, capable of generating electricity by force of a chemical reaction. In the presence of two electrodes, a fuel cell generates electricity.
Browse more Topics under Electrochemistry
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How does a fuel cell work?
Within every fuel cell are two electrodes, known as anode and cathode. These electrodes are the base around which the respective chemical reactions take place, making it possible for electricity to be generated. Every fuel cell consists of electrolytes, which essentially carry the electrically charged particles from the anode to the cathode and vice versa. Thus, electrolytes act as the catalyst which makes it possible for the chemical reaction to take place in a speedy manner.
Setup of fuel cells
A fuel cell fulfils the basic function of generating electricity, which could be used to power something as simple as a light bulb or an entire city. A simple chemical reaction, which takes place within a fuel cell, is responsible for the generation of electricity, which would ultimately return back to the cell, in order to complete the electric circuit.
This chemical reaction begins by introducing hydrogen atoms at the anode. A chemical reaction at this stage strips the hydrogen atoms of their electrons. Now, the hydrogen atoms carry a positive electric charge. The remaining negatively charged electrons provide current by way of the wires. Oxygen atoms are introduced at the cathode. They combine with the electrons left behind by the hydrogen atoms.
Depending on the type of cell, the oxygen atoms, together with the negatively charged electrons, would combine with the positively charged hydrogen ions at this stage or else, after travelling through the anode.
Role of Electrolyte
In the entire process, the electrolyte plays a major role in maintaining just the right proportion of ions to travel between the anode and the cathode. Any other freely travelling electrons could disrupt the ongoing chemical reaction in the fuel cell.
The combination of oxygen atoms with the hydrogen ions generates electricity and the process of generation shall continue as long as the fuel cell continues to receive the two atoms. In this chemical process, generation of water vapour takes place. Fuel cells are used in the transport vehicles such as cars and buses and as backup power units in electricity generating grids.
Thus, the electrolyte has a diverse role to play.
What are the Advantages of Fuel Cells?
- More efficient: Fuel cells prove to be much more efficient than a normal combustion engine since it converts chemical energy directly into electrical energy. In comparison to the other powering mechanism devices, the fuel cells are largely effective. They have a direct channel for energy to get converted, without undergoing a double conversion process. Thus, these are widely recommended.
- Saves wasteful emission: Unlike other cells which generate greenhouse gases in the process of energy conversion, fuel cells prove to be a major improvement as the only emission that they create are heat and water. Hence, great for the environment.
- More stable: The fuel cells assure minimal movement of various parts within and around the cell. They are, therefore, more reliable and convenient than a traditional cell.
- Takes care of natural resources: The process of atom separation and energy generation is very clean and an ergonomic method in fuel cells. Thus, beneficial for natural resources.
- Complimentary: Fuel cells by far present the most ergonomic solution if one wants to combine the cell with other technologies. You can make this combination of turbines and solar panels. Hence, known as complementary in nature.
- Scalable: You can use the fuels cells to generate electricity from a few mill watts to many megawatts. It also helps in powering a variety of devices such as cellphones and households. Thus, they are scalable.
Solved Examples for You
Question: What are the different type of fuel cells?
Answer: Among the many types of fuel cells are alkali cells. They make use of compressed hydrogen and oxygen in a solution of potassium hydroxide. Capable of producing up to 70% efficient energy, these cells operate at 150 – 200 degree Celsius. These cells require hydrogen as a fuel to permit generation of electricity.
The carbonate cells make use of high-temperature elements as the electrolyte. Under the influence of which, the generation of electricity takes place. In the phosphoric acid cells, the phosphoric acid is the electrolyte that helps in electricity generation. The efficiency of such cells varies from 40 to 80 percent. Proton Exchange Membrane make use of polymer electrolyte to generate electricity. They turn out to be almost 40 to 50 percent efficient. So, these are the different types of fuels cells that you need to know.