Portable equipment mobile computing

Batteries for portable equipment 2 Wh-100 Wh Flashlights, toys, power tools, portable radio and television, mobile phones, camcorders, lap-top computers... 

Consuming patterns have over recent years seen a dramatic increase in the use of portable equipment for entertainment and work (such as music and video players, laptop computers and mobile phones with multi-functionality). This has increased the demand for batteries, but at the same time found limitations of the battery technology that seem difficult to avoid even with increasing conversion efficiencies. Fuel cells with small-scale stores are an obvious solution to these problems, because the technical performance is already far beyond that of batteries (e.g., operating a state-of-the-art laptop computer for a few days rather than a few hours). The difference between these otherwise similar technologies is the external storage of chemicals for a fuel cell versus the internal storage in batteries. 

CD player will need less than 20 W. More specialised portable equipment includes field environmental monitors, medical mobile life-support systems and soldier commvmication and signalling devices used in military operations (Palo et al, 2002). Power requirements for such equipment would be in the range of 10-400 W. A standard size Li ion battery has a storage capacity of 750 mAh, and the largest one convenient for a laptop computer has a capacity of 3600 mAh. For a portable video camera, the standard Li ion battery may deliver 5 W at 7 V for about 1 h, while for the laptop at 12 V, the larger battery provides about 4 h at an average power consumption of 10 W. 

Rechargeable Li-ion cells are key components of the portable computing and telecommunication equipment required by today s information-rich, mobile society. A battery is composed of several electrochemical cells that are connected... 

Power requirements of portable hydrogen equipment such as cameras, mobile phones or laptop computers currently covered by batteries, typically of lithium ion type, could with a small fuel cell and some 10-20 g of directly or indirectly stored hydrogen prolong operational time by a factor of 5-10. A discussion of such options using direct methanol fuel cells is made in section 4.6. 

Recently we have developed spray-pulsed reactors equipped with alumi-monolith (alumite) catalyst plates for the efficient supply of hydrogen, using organic hydrides, to the micro-fuel cells of portable electrical appliances such as mobile phones, laptop computers and nurse robots, as shown in Fig. 

The electronics industry is continually searching for ways to make its equipment smaller - whether it be high-speed computers, or portable computers or mobile telephones, every model that appears is smaller than the one which preceded it. Each reduction in size worsens the problem of keeping the individual components cool enough to operate properly. This is the task for the ceramic package which supports the semiconductor circuit. 

Fuel cells are mainly used for combined heat and power (CH P), mobile power systems, vehicles, portable computers, mobile phones, and military communications equipment [24]. An overview is given in Figure 36.7. 

The nickel-cadmium battery was an improvement with a lifetime increased to about 25 years. Small Ni-Cd batteries proved to be very useful during the 1980s in connection with the dramatic development of battery-driven equipment such as video cameras, shavers, portable computers, mobile telephones, and so on. Cadmium is such an environmental problem that great demands were made for ecofriend-ly alternatives. 

Small power units with a capacity of tens of watts or milliwatts, providing energy for extended continuous operation of portable or transportable devices used in daily life, such as personal computers, videocameras, and mobile communication equipment, or in industrial applications such as signaling and control equipment... 

These LPBi are attractive as power sources for mobile gear including cellular phones, PDAi, notebook personal computers and portable audiovisual equipment. 

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