Primary cells costs

The demand for electrically operated tools or devices that can be handled independently of stationary power sources led to a variety of different battery systems which are chosen depending on the field of application. In the case of rare usage, e.g., for household electric torches or for long-term applications with low current consumption, such as watches or heart pacemakers, primary cells (zinc-carbon, alkaline-manganese or lithium-iodide cells) are chosen. For many applications such as starter batteries in cars, only rechargeable battery systems, e.g., lead accumulators, are reasonable with regard to costs and the environment. 

In Scotland, the cost of domestic mains electricity is 0.0713/kWh (in 1997). A D-size Leclanchd cell, delivering say 5 Wh, currently retails at 0.50. Thus, energy from the primary battery costs I00/kWh - a factor of over 1000 more expensive. For a 150 mWh zinc-silver oxide button cell, retailing at 1.50, the cost of energy is over 10 000/kWh ... 

The commercialization of RAM cells has presented a rather novel type of power source to the consumer market. First, they are ready to use as purchased and retain their charge well until used or after charging (Fig. 6.19), and thus behave rather like a primary battery in this respect. Second, they are not much more expensive than an alkaline manganese primary and thus are very cost-effective, even if capacity fade limits their use to 20 or so cycles. It will be interesting to discover how deeply this new technology penetrates the primary cell market in the near future. 

In the case of Li metal anode batteries, care must be taken to avoid temperatures which exceed the relatively low melting point of Li (180°C) as the molten metal is far more reactive than the solid, due to the instability of the passivating film on a hot molten liquid surface. This problem is sometimes circumvented in primary cells by the use of higher melting Li alloys, but pays the cost of a lower operating voltage. 

The worst drawback of the Ni/Cd battery is its cost, but progress has been made in recent years and Ni/Cd batteries are gradually replacing Leclanche cells and alkaline Zn/MnO primary batteries in many simple applications, such as mechanical toys and even flashlights. This is a very welcome development from the ecological point of view, since each Ni/Cd battery can replace hundreds of primary cells before it is thrown out. 

In practice the choice of the reporter gene is given by the specific characteristics of the cell line or primary cells used, and by the availability of appropriate analytical methods, whose costs may vary considerably. An alternative approach has been the use of a fusion protein between secretogranin, a secretory product of chromaffin cells, and alkaline phosphatase (Parmer et al., 1993). However, its direct use in the study of exocytosis has not been reported to our knowledge. 

The response time of EC sensors is typically 30 s and minimum detection limits range from 0.02 to 15 ppm. EC sensors range in price from 1,000 to 3,000. Calibration and maintenance are usually required every 3 months and sensor life averages 18 to 36 months. Replacement cells cost 175 to 300 depending on sensor type. (The primary manufacturers of EC monitors are Bionics Instrument Co., Ltd., Enterra Instrumentation Technologies, Gas Tech Inc., InterScan Corp., MDA Scientific Inc., National Draeger, Inc., Sierra Monitor Corp. and Telos Labs.)... 

The manufacturing lines for the production of rechargeable cylindrical cells are nearly identical with those of the low-cost primary cell version. This is an important cost-determining factor [17]. 

The alkaline zinc-manganese dioxide ceU was introduced in 1959 as a high-performance primary cell to replace the Leclanche (carbon-zinc) cell that was developed by Georges Leclanche in 1860 and is still the battery of choice in the developing countries because of its low cost. The zinc chloride cell was introduced... 

In addition to competition from lower-cost zinc-carbon cells, the AA-size alkaline cell has experienced significant competition from the more expensive rechargeable nickel-metal hydride (Ni-MH) and nickel-cadmium (Ni-Cd) cells and the lithium-iron sulfide primary cell (Li-FeS2) because of their excellent high-rate... 

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