C+-+different+types+of+fuel+cells


 * __About Fuel cells__**
 * **Fuel cell is when you convert chemical energy into electricity. **
 * **every fuel cells have two electrode, one being positive and other being negative(where they are called anode and cathode). And this is where electricity occurs. **
 * **They also have something called the electrolytes and catalyst, **
 * **electrolytes, which carries electrically charged particle from one electrode to the other, and catalyst, which speeds up the reaction at the electrodes. **
 * **in other words, it usually converts fuel ( such as hydrogen, natural gas, methanol, and gasoline) with the oxidants ( such as air or oxygen) into electricity. **
 * **fuels cells generate “ direct current ”  instead of going through the process of high temperature gas, this makes it much more efficient. This doesn ’ t mean that you don ’ t need temperature at all, you obviously need some to produce chemical reaction. **
 * **On the other hand, traditional method of electricity(coal-fired, hydroelectric) has same basic chemical reaction but it is worse because it burns the fuel and oxidant producing high-temperature gas (combustion), which makes more pollution then fuel cells. If we had same amount of fuel, fuel cells will be able to generate more electricity then traditional electricity method. **

=__Different types of fuel cells__= 
 * **different types of fuel cells are classified by their different degree of temperature and different types of electrolytes they use. **

__** 1. Proton Exchange Membrane (PEM) **__

 * **<span style="font-family: 바탕;">this is small and light **
 * **<span style="font-family: 바탕;">works at low temperatures about 80 ’ <span style="font-family: 바탕;">C **
 * <span style="font-family: 바탕;"> <span style="font-family: 바탕;">**<span style="font-family: 바탕;">works from hydrogen atoms entering the fuel cell at the anode and separates their electrons. After the hydrogen atom is “ <span style="font-family: 바탕;">ionized ” **<span style="font-family: 바탕;"> **and only have positive electrical charge left for it to go through, the negatively charged electrons go around the wires and meets up with the positive charge later on with the oxygen atoms. Producing H2O**.

**__<span style="font-family: 바탕;">** 2. Solid Oxide Fuel Cell ** __**

 * ==<span style="font-family: 바탕;">used commonly in large, stationary power plants. ==
 * == <span style="font-family: 바탕;">it uses high temperature about 1000 ’ <span style="font-family: 바탕;">C, which allow it to break down if it is used on and off repeatedly, but if it is used contantly it is known to be most stable and last the longest period of time out of all fuel cells. ==
 * == <span style="font-family: 바탕;">it has a hard ceramic electrolytes instead of liquid. It ’ <span style="font-family: 바탕;">s a mixture of zirconium oxide and calcium oxide to from crystal frame. ==

**__<span style="font-family: 바탕;">3. ** Alkali Fuel Cell ** __**

 * == <span style="font-family: 바탕;">has temperature about 150 ’ <span style="font-family: 바탕;">C to 200 ’ <span style="font-family: 바탕;">C ==
 * == <span style="font-family: 바탕;">in this cell, where potassium hydroxide in water is their electrolyte, (OH-) goes from cathode to the anode and at the anode, this (OH-) meets with hydrogen gas producing water and release electrons at the same time. ==
 * == <span style="font-family: 바탕;">this fuel cell is very considerable toward using for spacecraft. In fact, the NASA has used this for Space Shuttles, as well as the Apollo program. They are using it because of it is efficient by 70% and also it can provide drinking water for the astronauts. ==
 * == <span style="font-family: 바탕;">but the bad thing is that it is too expensive for it to build and they are now trying to figure out a way to make it cheaper. ==

**__<span style="font-family: 바탕;">4. ** Molten Carbonate Fuel Cell ** __**

 * == <span style="font-family: 바탕;">it is heated to 650 ’ <span style="font-family: 바탕;">C and it melts to conduct carbonate ions (CO3) from cathode to the anode. And the anode, hydrogen meets with this ion to produce, water, carbon dioxide, and electrons. ==
 * == <span style="font-family: 바탕;">it is almost same as the Solid Oxide fuel cells but the disadvantage of Molten carbonate fuel cell is that it is harder to work with liquid than Solid. ==

**__<span style="font-family: 바탕;">5. ** Phosphoric Acid Fuel Cell (PAFC) ** __**

 * == <span style="font-family: 바탕;">operates at temperature of 150 ’ <span style="font-family: 바탕;">C to 200 ’ <span style="font-family: 바탕;">C ==
 * == <span style="font-family: 바탕;">like it ’ <span style="font-family: 바탕;">s name, it uses phosphoric acid as the electrolyte. ==
 * == <span style="font-family: 바탕;">the positively charged hydrogen ions go through the electrolyte from anode to cathode and make water. ==
 * == <span style="font-family: 바탕;">advantage of this is that it can go over boiling point of water and still work, unlike other electrolytes that require water to conduct electricity. ==


 * ==A Basic Overview of Fuel Cell Technology. (n.d.). //National Museum of American History//. Retrieved November 20, 2010, from []==


 * ==Fuel Cell Basics. (n.d.). //FCTec Home Page//. Retrieved November 20,2010 from []==


 * ==Karthik, N. (n.d.). Fuel Cells Pros and Cons. //Buzzle Web Portal: Intelligent Life on the Web//. Retrieved November 20, 2010, from []==


 * ==Nice, K. (n.d.). HowStuffWorks "How Fuel Cells Work". //Howstuffworks "Auto "//. Retrieved November 20, 2010, from http://auto.howstuffworks.com/fuel-efficiency/alternative-fuels/fuel-cell.htm==