Apollo spacecraft

Although the principle of fuel cells has been known since 1838, practical applications arc fairly recent. The first applications were in the space program, where fuel cells powered the Gemini and Apollo spacecraft. In the 1960s and 1970s, fuel cells... 

The sulfonyl fluoride groups were hydrolyzed after the polymer had been processed into the membrane. One of the earliest applications of Nafion was in hydrogen/oxygen fuel cells such as those which provided electrical power for the Apollo spacecraft used for the manned expeditions to the moon in the early 1970s. 

Perfluorinated polyethers have also gained importance as actively functional materials. Ionic polymer membranes (e.g. DuPont s Nafion ) based on sulfonic acid-derivatized perfluoropolyethers have been used for nearly 30 years as ion-con-ducting membranes in chloralkali electrolysis cells, replacing the large amounts of toxic mercury used until then in the classic Castner-Kellner cells (Scheme 4.8.). One of the earliest applications of Nafion was as a membrane in the hydrogen-oxygen fuel cells which powered the Apollo spacecraft carrying the first men to the moon. 

Alkaline FCs (AFCs) use KOH as electrolyte and work at 70-90 C they are fully developed and very reliable (they powered on-board instrumentation of the Apollo spacecrafts and they power on-board instrumentation of the space Shuttles). Electrodes are mostly sintered nickel (anode) and sintered, lithiated nickel-oxide (cathode). 

As with the other fuel cell types, periods of pronounced ups and downs can be distinguished in R D for AFCs. Work in the United States, Europe, and a number of Asian countries evolved very vigorously after the 1960 demonstration of Bacon s battery and, more particularly, after the first flight of the Apollo spacecraft having the new power plant on board. 

January 27, 1967, Cape Kennedy, FL. The crew of the first Apollo spacecraft was conducting a launch site test of all space vehicle systems and procedures in preparation for an actual launch a month later. Gus Grissom, Ed White, and Roger Chaffee were inside the command module working to resolve a microphone problem during a hold in the countdown at T-10. Suddenly the crew reported a fire and emergency inside the command module. 

Metal-air batteries have proved easier to develop to a state of simplicity and reliability required from a power source than the fuel cells with gaseous or liquid fuels. Hence, although a type of hydrogen-oxygen fuel cell has reached such a state of perfection that it could be assigned the task of the main power supply in the cabin of the Apollo spacecraft, more recently the zinc-air battery seems to have taken its place. 

AFCs were used on the 1960 Apollo spacecraft [8], but because of their intolerance to carbon dioxide, their scope has been limited to places where pure hydrogen and oxygen are needed. The expected lifetime of AFCs is between 2,600 and 5,000 h, but AFCs have strong reliability (The Space Shuttle Orbiter produces electricity from an AFC with no backup power supply). 

A number of variants of fuel cells with alkahne electrolyte having a simpler design and milder working conditions (temperature and pressure) than the Bacon ceU were built and used in different applications. This work culminated in a number of fuel battery versions used in NASA s Apollo spacecraft and space shuttles (details in Chapter 6). 

Such fuel cells were used in the 1960s and 1970s to power Gemini and Apollo spacecraft. These cells are still widely deployed aboard the space shuttles, which clearly indicates their remarkable mechanical integrity and reliable electrical performance over extended periods. Because of compact size, improved reliability, and cost-effective performance under severe operating environments, these fuel cells are best suited for military and space applications involving UAVC, UUG, UUV, UAV, MRAP, and anti-IED operations. 

Figure 5.1 1.5-kW fuel cell from the Apollo spacecraft. Two of these units were used, each... 

Radioactive decay is accompanied by the evolution of heat, and radioactive nuclides can therefore be used as portable heat sources. One gram of Pu produces about 0.56 W of thermal power, primarily from alpha decay, and this isotope of plutonium has found use in space vehicles to drive small thermoelectric power units. Several satellites with Pu generators that produce 25 W have been deployed in space, and the Apollo spacecraft carried a Pu generator with a total weight of 14 kg that produced 50 W of power. A 73 W power supply fueled with 2.6 kg of Pu in the form of Pu02 produced the electrical power to run the scientific experiments of the Apollo lunar expedition. The satellite that sent the amazing photographs of Jupiter and the outer planets bade to Earth used a 50 W Pu power supply for this purpose. 

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