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Fuel cell
Fuel cell
One of the source of power for spacecraft is from the Heat. Please find all necessary info on this Power source. You should define what is Fuel cell. How can chemical reaction generate power? find an example of spacecraft use that. Everyone in the group should contribute 
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Both produce electricity. However, while a battery makes electricity from the energy it has stored inside the battery, a fuel cell makes its electricity from fuel in an external fuel tank.

by ABDUL QAYYUM bin ROSLAN

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How is electricity generated from fuel cells?

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How is electricity generated from fuel cells?

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by ABDUL QAYYUM bin ROSLAN

NASA has used liquid hydrogen since the 1970s to propel the space shuttle and other rockets into orbit. Hydrogen fuel cells power the shuttle's electrical systems,producing a clean byproduct - pure water, which the crew drinks. A fuel cellcombines hydrogen and oxygen to produce electricity, heat, and water.

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by ABDUL QAYYUM bin ROSLAN

Fuel Cell Use in the Space Shuttle

Fuel cells are used in the space shuttle as one component of the electrical power system. Three fuel cell power plants, through a chemical reaction, generate all of the electrical power for the vehicle from launch through landing rollout.

Before launch, electrical power is provided by ground power supplies and the onboard fuel cell power plants. Each fuel cell power plant consists of a power section, where the chemical reaction occurs, and a compact accessory section attached to the power section, which controls and monitors the power section's performance.

This is one of the three fuel cells that make up the generating system that provides electrical power to the space shuttle orbiter. The unit is a little more than a foot high and weighs approximately 200 pounds. Credit: NASA

The three fuel cell power plants are individually coupled to the reactant (hydrogen and oxygen) distribution subsystem, the heat rejection subsystem, the potable water storage subsystem, and the electrical power distribution and control subsystem. The fuel cell power plants generate heat and water as by-products of electrical power generation.

The excess heat is directed to fuel cell heat exchangers, where the excess heat is rejected to Freon coolant loops. The water is directed to the potable water storage subsystem.

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Each of entry shouldn't be anynomous. I have asked you to log in to write in padlet. Pkease write your name on each entry that you have wtitten

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The Improvement in Application of Fuel Cell

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The Improvement in Application of Fuel Cell

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by: Mohamad Akmal Ridzuan Bin Radzi

The NASA Glenn Research Center is the focal point for NASA's fuel cell research and development. Glenn helped to develop the alkaline fuel cells that are the primary source of power on the Space Shuttles and developed fuel cells for electric vehicles and energy-storage systems. Glenn researchers continue to look for ways to improve fuel cells.

These improved fuel cells may soon be seen in many areas of our lives. For example, fuel cells may soon provide auxiliary equipment power on commercial aircraft. They could be used in cars, commercial powerplants, and personal electronics. Glenn is developing and investigating fuel cells for emissions-free aircraft, the International Space Station, reusable launch vehicles, a Mars airplane, and a Space Shuttle upgrade, as well as for systems to produce electricity and store energy on the Moon and Mars.

Alkaline fuel cells have been the primary source of electrical power on human spaceflight systems for over four decades. However, alkaline fuel cells use a costly, aging technology. Much work must still be done before improved fuel cells can be used in spacecraft, which operate at extreme altitudes and low temperatures for extended durations. This technology will enable new space exploration missions as well as fuel savings, quiet operation, and reduced emissions for aircraft.

the other type of improvements are being made in other industry, and Toshiba unveiled prototype fuel cells for laptops and other applications generating 20 to 100 watts. The units are compact and the specific energy is comparable with that of a NiCd battery. Meanwhile, Panasonic claims to have doubled the power output with a similar size, specifying a calendar life of 5,000 hours if the fuel cell is used intermittently for 8 hours per day. The low longevity of these fuel cells has been an issue to be reckoned with.

Refrerence : https://www.nasa.gov/centers/glenn/technology/fuel_cells.html

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By : ABDUL QAYYUM bin ROSLAN

website: http://www.fuelcellstore.com/blog-section/history-of-fuel-cells

Fuel cells have been known in the scientific community for about 150 years. They began to be explored in the 1800s, and have been extensively researched during the second half of the twentieth and early twenty-first century.  A summary of fuel cell history is shown in Figure 1.

In 1800, William Nicholson and Anthony Carlisle described the process of using electricity to break water into hydrogen and oxygen. William Grove is credited with the first known demonstration of the fuel cell in 1839. Grove saw notes from Nicholson and Carlisle and thought he might “recompose water” by combining electrodes in a series circuit, and soon accomplished this with a device called a “gas battery.” It operated with separate platinum electrodes in oxygen and hydrogen submerged in a dilute sulfuric acid electrolyte solution. The sealed containers contained water and gasses, and it he observed that the water level rose in both tubes as the current flowed. The device was nicknamed the “Grove cell,” and it consisted of a platinum electrode immersed in nitric acid, and a zinc electrode immersed in zinc sulfate. It generated about 12 amps of current at approximately 1.8 volts.

Friedrich Wilhelm Ostwald (1853–1932), one of the founders of physical chemistry, provided a significant portion of the theoretical understanding of fuel cells. In 1893, Ostwald experimentally determined the roles of many fuel cell components.

Ludwig Mond (1839–1909) was a chemist that spent most of his career developing soda manufacturing and nickel refining. In 1889, Mond and his assistant Carl Langer performed numerous experiments using a coal-derived gas. They used electrodes made of thin, perforated platinum, and had many difficulties with liquid electrolytes. They achieved six amps per square foot (the area of the electrode) at 0.73 volts.

Charles R. Alder Wright (1844–1894) and C. Thompson developed a similar fuel cell around the same time. They had difficulties in preventing gasses from leaking from one chamber to another. The leaking and a few other design flaws prevented the battery from reaching voltages as high as 1 volt. Wright and Thompson felt that if they had more funding, they could create a more robust cell that would provide adequate electricity for many applications.

The French team of Louis Paul Cailleteton (1832–1913) and Louis Joseph Colardeau came to a similar conclusion, but thought the fuel cell electrochemical process was not practical due to needing “precious metals.” Also, many papers published during that period said that coal was extremely inexpensive so that a new system with a higher efficiency would not decrease the prices of electricity drastically.

William W. Jacques (1855–1932), an electrical engineer and chemist, did not pay attention to these critiques and startled the scientific world by constructing a “carbon battery” in 1896. Air was injected into an alkali electrolyte to react with a carbon electrode. He thought he was achieving an efficiency of 82 percent but obtained only an 8-percent efficiency.

Emil Baur (1873–1944) of Switzerland and several of his students conducted many experiments on different types of fuel cells during the early 1900s. He worked on high-temperature devices, and a unit that used a solid electrolyte of clay and metal oxides.

O. K. Davtyan of the Soviet Union did many experiments to increase the conductivity and mechanical strength of the electrolyte in the 1940s. Many of the designs did not yield his desired results, but Davtyan’s and Baur’s work contributed to the necessary preliminary research for today’s current Molten Carbonate Fuel Cell (MCFC) and Solid Oxide Fuel Cell (SOFC) devices.

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by: mohd norherman shauqee
NASA is also pursuing a variety of alternative power sources for aerospace vehicles. One of those alternatives is fuel cells. To achieve improved performance, NASA is building on decades of success with Gemini, Apollo and Shuttle → alkaline fuel cell power system development and operations. The agency has also pursued other types of fuel cells, such as methane, metal-air and hydrogen peroxide.

A phase-one proton exchange membrane fuel cell design for space exploration developed by Teledyne. Credit: NASA

In recent years, the Department of Energy (DOE) and private industry have made significant advances in the development of Proton Exchange Membrane (PEM) fuel cells using hydrogen and air as the fuel and oxidant for ground-transportation applications. Additionally, the DOE and the ground power industries are working on emerging Solid Oxide Fuel Cells (SOFC) for ground-based power generation. NASA is building upon these PEM and SOFC developments to dramatically advance fuel cell technologies, providing reliable, compact and high-energy renewable power sources for aerospace applications.

With the aid of industry and universities, NASA is addressing aerospace challenges that include reduced gravity, low or no atmospheric pressure, extreme temperatures, dynamic vibration, shock loads and extended duration operations. For airless space applications, the focus is on closed-cycle regenerable PEM technology. The targeted space systems feature power outputs of 1 to 10 kilowatt systems (eventually scalable up to 100 kilowatts), compact sizing (250 to 350 watts per kilogram), and high reliability for long lives (10,000 hours). With the appropriate investments and collaborations, NASA intends to revolutionize aerospace power generation to enable new capabilities. Experts at Glenn, the Jet Propulsion Laboratory, the Johnson Space Center and Kennedy are leading these fuel cell efforts

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by: Muhammad Qayyum bin Syed jowbur ali

ALKALINE IS FUEL CELL THAT BEEN USED IN SPACE.

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-Saravanan A/L Thunsh Kodi

Fuel cell used in Apollo

The fuel cell models displayed here contain many individual fuel cells along with the plumbing and sensors required to supply reactants and keep the cell at the proper temperature. The reactants were stored in separate tanks in liquid form to reduce space. This required keeping the oxygen at -173°C (-280°F) and at a pressure of 63.26 kilograms per square centimeter (245 pounds per square inch). Waste heat from the fuel cells was used to bring the reactants to gaseous form before they entered the cell. The Apollo fuel cell operated at a temperature of about 206°C (400°F) and the Gemini cell at about 65°C (150°F).

An Apollo spacecraft carried three hydrogen-oxygen fuel cells in the service module. Each unit contains 31 individual fuel cells connected in series and operates at 27 to 31 volts. Normal power output is 563 to 1420 watts, with a maximum of 2300 watts. Primary construction materials are titanium, stainless steel, and nickel.

For space applications, fuel cells have another advantage over conventional batteries: they produce several times as much energy per equivalent unit of weight. When oxygen and hydrogen combine to form water, energy is released because the electrons in the water molecule are in a lower energy state than those in the gas molecules. In a combustion reaction, as in a rocket engine, the energy appears as heat. In a fuel cell some of it —about 50-60%—is converted directly to electrical energy. As fuel cells operate, oxygen and hydrogen combine to produce water as well as electrical power. Apollo crews used this water for drinking.

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-Saravanan A/L Thunsh Kodi

Fuel cell used in Gemini  Gemini fuel cell diagram

The Gemini spacecraft, which preceded the Apollo spacecraft, carried two hydrogen-oxygen fuel cell battery sections in its adapter/equipment section.

Each battery section contains three stacks of fuel cells with plumbing. The stacks are connected in parallel and can be switched in and out of use individually. Each stack has 32 individual cells connected in series and produces about 490 amperes at 23 to 26 volts. Maximum power output per battery section is about one kilowatt.

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ADVANTAGES OF FUEL CELL COMPARED WITH BATTERIES 

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ADVANTAGES OF FUEL CELL COMPARED WITH BATTERIES 

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-Saravanan A/L Thunsh Kodi

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Who needs batteries when you've got a hydrogen fuel cell

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Fuel cells are quickly becoming the means of powering larger unmanned autonomous vehicles that must operate for days or weeks.

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Construction of a high-temperature Proton Exchange Membrane Fuel Cell

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Construction of a high-temperature Proton Exchange Membrane Fuel Cell

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-Saravanan A/L Thunsh Kodi

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Saravanan A/L Thunsh Kodi
Mohamad Afiq Syarafuddin Bin Rosli
Mohamad Akmal Ridzuan bin Radzi
Mohamad Norherman Shauqee bin Mohamad Raihan
Abdul Qayyum bin roslan
Muhammad Arif Syafiq bin Md Sharif
Muhammad Qayyum bin Syed Jowbur Ali

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-Saravanan A/L Thunsh Kodi

A fuel cell is an electrochemical device that combines hydrogen fuel with oxygen to produce electricity, heat and water. The fuel cell is similar to a battery in that an electrochemical reaction occurs as long as fuel is available. Hydrogen is stored in a pressurized container and oxygen is taken from the air. Because of the absence of combustion, there are no harmful emissions, and the only by-product is pure water. So pure is the water emitted from the proton exchange membrane fuel cell (PEMFC) that visitors to Vancouver’s Ballard Power Systems were served hot tea made from this clean water.

Fundamentally, a fuel cell is electrolysis in reverse, using two electrodes separated by an electrolyte. The anode (negative electrode) receives hydrogen and the cathode (positive electrode) collects oxygen. A catalyst at the anode separates hydrogen into positively charged hydrogen ions and electrons. The oxygen is ionized and migrates across the electrolyte to the anodic compartment, where it combines with hydrogen. A single fuel cell produces 0.6–0.8V under load. To obtain higher voltages, several cells are connected in series. Figure 1 illustrates the concept of a fuel cell.

| Figure 1: Concept of a fuel cell.
The anode (negative electrode) receives the hydrogen and the cathode (positive electrode) collects the oxygen.

Fuel cell technology is twice as efficient as combustion in turning carbon fuel to energy. Hydrogen, the simplest chemical element (one proton and one electron), is plentiful and exceptionally clean as a fuel. Hydrogen makes up 90 percent of the universe and is the third most abundant element on the earth’s surface. Such a wealth of fuel would provide an almost unlimited pool of clean energy at relatively low cost.

With most fuels, hydrogen is bonded to other substances and “unleashing” the gas takes energy. In terms of net calorific value (NCV), hydrogen is more costly to produce than gasoline. Some say that hydrogen is nearly energy neutral, meaning that it takes as much energy to produce as it delivers at the end destination.

Storage of hydrogen poses a further disadvantage. Pressurized hydrogen requires heavy steel tanks, and the NCV by volume is about 24 times lower than a liquid petroleum product. In liquid form, which is much denser, hydrogen needs extensive insulation for cold storage.

Hydrogen can also be produced with a reformer by means of extraction from an existing fuel, such as methanol, propane, butane or natural gas. Converting fossil fuel into pure hydrogen releases some leftover carbon, but this is 90 percent less harmful than what comes from the tailpipe of a car. Carrying a reformer would add weight to the vehicle and increase its cost; reformers are also sluggish. The net benefit of hydrogen conversion is in question because it does not solve the energy problem.

Sir William Grove, a Welsh judge and gentleman scientist, developed the fuel cell concept in 1839, but the invention never took off. This was during the development of the internal combustion engine (ICE) that showed promising results.  It was not until the 1960s that the fuel cell was put to practical use during the Gemini space program. NASA preferred this clean power source to nuclear or solar power. The alkaline fuel cell system that was chosen generated electricity and produced drinking water for the astronauts.

High material costs made the fuel cell prohibitive for commercial use. The fuel cell core (stack) is expensive and has a limited life span. Burning fossil fuel in a combustion engine is the simplest and most effective means to harness energy, but it pollutes.

High cost did not discourage the late Karl Kordesch, the co-inventor of the alkaline battery, from converting his car to an alkaline fuel cell in the early 1970s. He mounted the hydrogen tank on the roof and placed the fuel cell and backup batteries in the trunk. According to Kordesch, there was enough room for four people and a dog. He drove his car for many years in Ohio, USA, but the only problem, Kordesch told me in person, was that the car did not pass inspections because it had not tail pipe.

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By: Mohamad Afiq Syarafuddin Bin Rosli

One important use of fuel cells is to provide electrical power in spacecraft.
Some of the reason for using fuel cell in spacecraft:-
1) They have no moving parts
2) They are compact (small for the amount of electricity they produce)
3) They are lightweight (important when keeping the mass of the craft low at   launch-off)
4) They can deliver high power output
5) They are not affected by night times in low earth orbit compared by solar cell.

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By-MUHAMMAD ARIF SYAFIQ BIN MD SHARIF 129161
A fuel cell combines a fuel (hydrogen or hydrogen source) with an oxidizer (oxygen or air) to produce electrical power.

Image above: A fuel cell converts hydrogen and oxygen into water, producing electricity and heat in the process. It has two electrodes, the negative anode and positive cathode, separated by an electrolyte that only allows specific ion flows. Fuel is delivered to the anode and oxygen to the cathode. Credit: NASA

Fuel cells can use hydrogen directly, or they can obtain hydrogen from another fuel, like liquid methanol (wood alcohol), which is renewable and can be transported more easily than hydrogen. With hydrogen fuel, heat and water are the only byproducts. With methanol fuel, heat and water are still the major byproducts, along with only a fraction of the carbon dioxide and none of the other pollutants produced by a gasoline-burning engine.

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NASA - Fuel Cells: A Better Energy Source for Earth and Space

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One of the source of power for spacecraft is from the Heat. Please find all necessary info on this Power source. You should define what is Fuel cell. How can chemical reaction generate power? find an example of spacecraft use that. Everyone in the group should contribute