Propulsion of vehicles

For vehicular applications, fuel cell systems need to be different from stationary power generation. Available space in vehicles is much more critical and fast response times and start-up times are required. 

2 NECAR4, a fuel cell vehicle with a PEM system operated with liquid H2 [71]. 

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The major factor that has influenced the development of fuel cells over the last few years is the worldwide concern of the enviromnental consequences of the use of fossil fuels in the production of electricity and for the propulsion of vehicles. Fuel cells seem to be the best solution for clean, efficient and non-hazardous energy. 

The propulsion of vehicles by fuel cell may well require the development of a hydrogen mine. Such a plant would serve the needs of organisations such as Air Products or Methanex, who might even be its developers Combustion-heated reformers would be displaced from the hydrogen industry. 

The poor efficiencies of coal-fired power plants in 1896 (2.6 percent on average compared with over forty percent one hundred years later) prompted W. W. Jacques to invent the high temperature (500°C to 600°C [900°F to 1100°F]) fuel cell, and then build a lOO-cell battery to produce electricity from coal combustion. The battery operated intermittently for six months, but with diminishing performance, the carbon dioxide generated and present in the air reacted with and consumed its molten potassium hydroxide electrolyte. In 1910, E. Bauer substituted molten salts (e.g., carbonates, silicates, and borates) and used molten silver as the oxygen electrode. Numerous molten salt batteiy systems have since evolved to handle peak loads in electric power plants, and for electric vehicle propulsion. Of particular note is the sodium and nickel chloride couple in a molten chloroalumi-nate salt electrolyte for electric vehicle propulsion. One special feature is the use of a semi-permeable aluminum oxide ceramic separator to prevent lithium ions from diffusing to the sodium electrode, but still allow the opposing flow of sodium ions. 

All fuel cells for use in vehicles are based on proton-exchange-membrane fuel cell (PEMFC) technology. The methanol fuel-processor fuel cell (FPFC) vehicle comprises an on-board fuel processor with downstream PEMFC. On-board methanol reforming was a development focus of industry for a number of years until around 2002. Direct-methanol fuel cells (DMFC) are no longer considered for the propulsion of commercial vehicles in the industry (see also Chapter 13). 

Auxiliary power units are devices that can provide all or part of the non-propulsion power for vehicles. Such units are already in widespread use in a range of vehicle types and for a variety of applications, in which they provide a number of potential benefits (see Figure 1-10). Although each of these applications could provide attractive future markets for fuel cells, this section will focus on application to on-road vehicles (specifically trucks). 

Pisehinger, S. The future of vehicle propulsion-combustion engines and alternatives. Top. Catal. 2004, Volume 30/31, 5-16. 

Thomas (Ref 5) claims systems useful for propulsion of rocket shells, JATO airborne vehicles, consisting of a mixt of finely divided MeN03 with fuels which are nitro compds, such as NGu, Amm Picrate, etc. The addn of A1 can modify burning characteristics. Binders are. chlorinated polyphenyls or urea resins. The ingredients are milled on rolls just hot enough to soften the resin and then the mixt is pelleted... 

In many situations, the propulsion and vehicle system requirements cannot be met by the available propellant combinations. Such problems are often solved by tailoring. This involves the formulation of a desirable set of characteristics by mixing selected ingredients. Several examples of new propellants that have been developed in this manner are noted below. 

In this section, the main characteristics of alternative electrical energy storage systems, such flywheels and super capacitors, are described, as these devices might play an important role in the development of vehicles powered by electric propulsion systems. 

Today, a storage battery that is mainly used for propulsion of a vehicle and is recharged from an external energy source is referred to as a traction battery . Typical applications are forklift trucks, automatically guided vehicles (AGVs) in modern production and logistics, and on-road electric vehicles (EVs). 

GREET includes a variety of vehicle propulsion technologies and transportation fuels, of which fuelcell vehicle technologies and fuel-cell fuels are a subset. Table 1 lists the fuel-cell fuels included in the GREET model. GREET can simulate multiple options for a given pathway. For example, GREET... 

Fuel tank means a tank other than a cargo tank, used to transport flammable or combustible liquid, or compressed gas for the purpose of supplying fuel for propulsion of the transport vehicle to which it is attached, or for the operation of other equipment on the transport vehicle. US 171.8... 

At the end of the twentieth century, consumption of petroleum fuels increased significantly on a worldwide basis and the first symptoms of a petrol crisis appeared. Automobile manufacturers decided to reduce petrol consumption by combining an electrical engine with an internal combustion engine to propel the vehicle. Thus, the hybrid electric vehicle (HEV) was devised. Depending on the involvement of the electric motor (battery) in the propulsion of the vehicle, several types of HEVs have been developed. 

Any petroleum oil carried in a fuel tank for the piupose of supplying fuel for propulsion of the transport vehicle to which it is attached and... 

This research was sponsored by the U.S. DOE, Office of Vehicle Technologies, as a part of the Propulsion Materials Program, under contract DE-AC05-00OR22725 with UT-Battelle, LLC. The authors thank Drs. Michael J. Lance and Amit Shyam for... 

In selected cases described in this section, batteries provide the main source of propulsion of the vehicle. However, hybrid systans are beconung more popular due to their specifications flexibility and variety of different power source devices available for hybridization [45]. In hybrid power systems, batteries can be coupled with fuel cells, capacitors, supercapacitors, hydrocarbon fuel engines, or diesel generators. The role of the battery in such hybrids is typically to assist in loadbalancing and/or to provide more efficiency in meeting power requirements [46]. More detailed discussion of hybrid power systems is included in Chap. 6 of this book. 

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