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Fuel Cells Essay, Research Paper

Today many Americans face a lot of economical and environmental challenges. There is pollution in the air, water, and even lying on the ground all around them. Oil and gasoline products derived from petroleum are skyrocketing in price. Brownouts and blackouts are occurring in heavy power usage areas in the United States. What do these problems all have in common; a common solution: Fuel cell technology. A fuel cell is as defined by Webster is an electrochemical generator that produces direct current from a chemical reaction, as from combining oxygen and hydrogen. When hydrogen and oxygen are combined in the fuel cell the results are direct electric current and the production of water as waste. Fuel cells are very efficient in producing electricity without the harmful pollutants. In a fuel cell there are no moving parts so there is no noise. They have excellent reliability and long operation lives. Fuel cells can use multiple fuels such as natural gas, methanol, gasoline, and hydrogen to operate (ballard.com). This sounds almost like a science-fiction fantasy, but in reality they do exist.Many people that have heard of fuel cells believe it is a relatively new discovery in technology. When actually fuel cells have been around since the early 1800’s says Klein. The first true fuel cell was invented by a man the name of William Robert Grove (Klein 99). Grove was a Judge that found recreation in science, especially electrochemistry. He constructed a cell of what he called a “gaseous voltaic battery”, according to Klein. The cell was made of two well-separated electrodes formed from platinum foil, soaked in diluted sulfuric acid (Klein 100). Grove believed that the platinum would act as a catalyst to speed up the reaction, and the sulfuric acid would be the electrolyte or conductor. Grove used pure hydrogen and oxygen gas to accomplish the energy reaction. The reaction was a success producing voltage and releasing water as a byproduct. Klein explains Groves process like this:Ionization took place among sulfuric acid molecules in electrolyte solution, resulting in two positively charged hydrogen ions and one sulfate ion with double negative charge. When molecules of hydrogen gas come into contact with the wet platinum electrode, “chemisorption” occurred. It meant that each formerly paired hydrogen molecule crowded against the platinum electrode as two separate activated atoms of hydrogen. These atoms became hydrogen ions and surrendered their single electrons to the platinum metal, through which the stream of electrons flowed into the external circuit. A like electron flow returned to the cell through the opposite electrode. The resulting negative charge on that electrode attracted to it the wandering hydrogen ions from the electrolyte. Ions reaching the electrode receive the lacking electron, becoming neutral highly active hydrogen atoms. At that same electrode the oxygen atoms separate and join the hydrogen atoms producing water (Klein 102-3). This is how a basic hydrogen-oxygen fuel cell works in layman’s terms: The hydrogen is sent through the electrolyte bath containing metal plates. It reacts with oxygen, which produces electric current and water. Multiple cells can be stacked together to increase the voltage.Fuel cells first gained attention in the early 1960’s. NASA used fuel cells on several of their space missions. According to Klein on august 21, 1965 Gemini V launched from Cape Kennedy with two astronauts and a fuel cell system designed to operate the shuttle in space. The system made by General Electric was intended to deliver power at rates of up to two kilowatts during an eight-day space mission (Klein 10). Klein says the fuel cell system weighted about four and a half times less then a storage battery that would have only supplied power for four days. The first Apollo mission combined more than fifty pounds of compressed hydrogen gas with 425 pounds of compressed oxygen gas. The fuel cell extracted the electric current and released around sixty gallons of drinkable water, eliminating the need for heavy water tanks onboard (Klein 8). This is a huge advantage of fuel cell use in the space program where weight is an important factor. Since the use of fuel cells in the space program, the interest has been limited to academic and U.S. department of energy research says Ferry. This is because of the high cost of platinum. When it was introduced to the space program cost was not an issue, performance was the only thing that mattered. Today’s fuel cells operate the same as the 1960’s space programs but some of the parts have changed. According to Alex Scott there are five basic types of fuel cells, each with advantages and disadvantages for stationary and mobile uses. For all of the families of fuel cells it is the electrolyte that defines the type of cell. The first type of cell is the Phosphoric acid cell. This cell operates at low temperatures. It is typically for use as a backup power generator for critical situations like hospitals. Steam is a byproduct of the cell. Next is the solid oxide cell. The cell uses zirconium oxide for the electrolyte. The cell can generate hydrogen directly from the hydrocarbon fuel so it does not have to go through a separate process to form hydrogen. Next is the Direct Methanol fuel cell or the DMFC. This cell runs on methanol and there is no oxidation of hydrogen. Liquid methanol is the fuel being oxidized. This cell is being considered in the automotive industry. This fuel cell releases a small amount of carbon dioxide as a byproduct. Next to last is the Molten Carbonate. This cell is a high temperature cell that can use most fuels for operation. The temperature of operation is so high it can only be used in industrial applications. The last family of cells is the Polymer Electrolyte Membrane or “PEM”. This fuel cell is the most widely used and studied fuel cell. It is very light and

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