On-board power

Nickel-cadmium batteries with thin sintered plates are used for on-board power supplies in aircraft, helicopters, tanks and military vehicles where their excellent low temperature, high rate performance is an important attribute. Modern 40 Ah cells designed for airborne use can deliver 20 kW of instantaneous power at 25°C and over 10 kW at —30DC. Again, the high cost of this system compared with that of lead-acid batteries has restricted its use. 

Figure 4.11. Proposed submarine propulsion system based on PEM fuel cells and liquid hydrogen and oxygen. (From G. Sattler (2000). Fuel cells going on-board. /. Power Sources 86,61-67. Used by permission from Elsevier.)...

Sattler, G. (2000). Fuel cells going on-board. /. Power Sources 86, 61-67. 

On the other hand, high pressure determines a higher energy consumption associated to the compressor, then a CEM can be used to recover some energy from the pressurised cathode exhaust stream (Fig. 4.3b). This solution adds complexity to the on-board power plant and can be usefully applied in medium large-size fuel cell power trains (10-100 kW). 

It is increasingly clear that eventually, the law is going to place significant additional EMI requirements on all on-board power converters and any power supply, off-line or otherwise, working inside telecom equipment. Therefore, in the not so unforeseeable future, we could soon all be routinely testing the outputs of every power supply in much the same manner as we test their inputs today. In fact even as of now, many of the big telecom equipment manufacturers, of their own volition, routinely comply with CISPR 22 limits on both the inputs and outputs of their telecom power supplies. Of course, instead of the special proposed ISN, they have just gone ahead and used the more readily available input LISN to test the outputs too. 

Savino, S. E. Suranyi, G G. Application Guidelines for On-Board Power Converters , Tyco Electronics Application Note, June 1997... 

Plutonium-238 is used to provide on board power for electronic systems in satellites. Plutonium- 239 is used primarily in nuclear weapons. Most plutonium is found combined with other substances, for example, plutonium dioxide (plutonium with oxygen) or plutonium nitrate (plutonium with nitrogen and oxygen). More information about the properties and uses of plutonium can be found in Chapters 3, 4, and 5. 

Bohorquez et al. designed, buUt, and tested both single-rotor and coaxial dual-rotor vehicles they dubbed MICOR [4]. The single-rotor device had a takeoff weight of 100 g and was able to hover for 3 m using its on-board power supply. 

The most common use is radioisotope-powered thermoelectric generators for the electric loads on board. Power is typically about 1 kWe, subdivided between three or more units. Radioisotope-powered heat generators (2.7 g of plutonium, 1 W) are currently used to guarantee the suitable thermal conditions for the equipment on board during a mission. 

Examples of generators are presented with power outputs ranging om micro-milliwatts to kilowatts and include an early Russian examples from the 1950 s to NASA s multihundred watt systems that provide on-board power to deep space missions. Improvements in generator performance due to advances in material figure- of- merit, thermoelement design and module configurations are reviewed. 

On-Board Power Supply with Fuel Cells... 

Siemens tested on-board power supply for submarines with a 100 kW alkahne fuel cell on the U1 submarine of the German Navy in 1988. TTie 6 month test runs were very successful and constituted the basis of the German Navy s decision to equip the new 212 generation of submarines with fuel cells. However, the more recent PEFC development was used. The fuel ceU developed by Siemens is based on a Nation membrane with a high platinum loading and a metalhc bipolar plate with an elastomer seal, ah developed specificaUy for the utihzation of H2/O2. 

Figure 9.38 Increasing on-board power demand of passenger cars in watts versus time [442].

Real-time switching between gasoline and diesel fuel could actually be demonstrated at different load levels without any apparent change to the performance of the system 621). However, low sulfur fuels were utilised exclusively. The fuel processor was tested in combination with an Andromeda fuel cell stack developed by Nuvera. No apparent difference could be observed when operating the combined system with ethanol, gasoline or diesel fuel [621]. However, recent activities of these workers have been directed towards a lOkWd on-board power plant or auxiliary power unit [621]. 

The Alkaline Fuel Cell (AFC) was one of the first modern fuel cells to be developed, beginning in 1960. The application at that time was to provide on-board electric power for the Apollo space vehicle. Desirable attributes of the AFC include excellent performance compared to other candidate fuel cells due to its active O2 electrode kinetics and flexibility to use a wide range of electro-catalysts. The AFC continues to be used it now provides on-board power for the Space Shuttle Orbiter with cells manufactured by UTC Fuel Cells. 

Although not necessarily involving a formal potentiostat, a broadly applicable and inexpensive, on-board power source was recently developed by Liu and Crooks [46]. As a very clever alternative, a metal/air battery that drives electrolytic reactions was integrated with a paper-based sensor, defined by wax printing. Electrical contact was made to the... 

A specialized type of Li-ion battery developed for semi-conductor and printed circuit board (PCB) applications are thin-film, solid-state devices. These batteries which employ ceramic negative, solid electrolyte and positive electrode materials, can sustain high temperatures (250°C), and can be fabricated by high volume manufacturing techniques on silicon wafers which are viable as on-chip or on-board power sources for microelectronics. Batteries of this type can be very small, 0.04 cm x 0.04 cm x 2.0 fjm. For microelectronics applications, all components must survive solder re-flow conditions, nominally 250°C in air or nitrogen for 10 minutes. Cells with liquid or polymer electrolytes cannot sustain these conditions because of the volatility or thermal stability of organic components. Further, cells that employ lithium metal also fail as solder re-flow conditions exceed the melting point of lithium (180.5°C). 

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