Page 397 - Battery Reference Book

34/4 Silver batteries

6. Computers and microprocessors Portable power have achieved ranges of up to 350 miles in one dis-
for microprocessors and data banks, computer- charge, making them a very attractive alternative to
ized portable weighing scales, portable paddles in lead-acid batteries, which give a maximum range of
stores for inventory of stock fed to computer. about 70 miles.
7. Vehicles Power for electric vehicles. A motorbike powered by a silver-zinc battery has
8. Hobbies Remote-controlled model planes, ships, broken the electric bike world speed record by achiev-
trains and vehicles. ing 165.3 milesh. The battery, developed by Eagle
9. Aerospace and communications Balloon flight- picher, weighed 40kg, and had a nominal capacity of
powering instrumentation, rocket instnunentation, 100 Ah and an energy content of 4680 W h.
stabilized aerostatic balloons (tethered), portable
telephones in future computerized systems, Submarines
portable heavy-duty radios, sonobuoy batteries,
telemetry, energy storage for solar converters, Yardney quote the following example of the use of
launchers (satellites), planetary probes, energy silver-zinc batteries in submersibles in the place of
systems, helicopter and aircraft batteries, portable batteries conventionally used in this application. A
receivers and transmitters, emergency systems for silver-zinc battery system designed to replace the
emergency lighting and power at airports. lead-acid battery in the US Navy’s turtle (DSV-3)
10. Military Torpedoes, submarines, noiseless-run- would make the difference shown in Table 34.2.
ning combat vehicles, rocket power supply, radio
transmitters, night vision equipment.
Table 34.2

34.2.1 Specialized applications Lead-acid Silver-zinc
battery
battery
Some silver-zinc batteries are used in military ap-
0.78
0.78
plications; some other specialized applications are Volume (m3) 1735 1643
Weight (kg)
described below. Endurance at 1.5 knots (h) 10 31
Endurance at 2.5 knots (h) 1.9 6.07
Space applications
Secondary (and high-rate primary) batteries were spe-
cially developed for the US Space Administration The critical profit parameter in operating sub-
(NASA) Apollo ILM Saturn programme. A total of mersibles is the cost per hour while submerged. If the
24 secondary and primary silver-zinc batteries were following assumptions are made, it would appear that,
used on each Saturn V vehicle. The Moon Buggy or on cost considerations, the silver-zinc battery is more
Lunar Rover used for driving on the surface of the attractive than the lead-acid battery:
moon in 1971 was powered by two manually activated
secondary silver-zinc batteries. This vehicle reached 1. Cost of lead-acid battery, $15 000.
speeds of 5-6 mile&. The Agena, a workhorse 2. Cost of replacement of silver-zinc battery, $60 OOO.
launch vehicldsatellite since 1959, is powered with 3. Incremental cost of silver-zinc battery, $45 000.
silver-zinc batteries. When originally developed, in 4. Daily operating cost of the total system, $2200.
1959, these batteries had a power density of 36 W hkg. 5. Daily incremental cost of silver-zinc battery
This has since been increased to 53 W hkg. (2 year life), $65.

Electric vehicles With a lead-acid batteq, a submersible can explore
for 1.9h at 2.5 knots for a distance of 4.75 miles.
Eagle Picher have developed an electric car, the Silver
Eagle, utilizing 174 space-type secondary silver-zinc Thus, the cost per hour submerged is $1158. With a
silver-zinc battery, submersibles could explore 6.07 h
batteries as the power source. These tests were con- at 2.5 knots for a distance of 15.2 miles. Thus the cost
ducted in 1971 and 21 world speed records were bro- per hour submerged is $373, and the potential saving
ken, most of which stand today. is $785/h.
The Silver Eagle weighed 517 kg, including 118 kg
of batteries. The vehicle was 409 cm long, 85 cm high,
129 cm wide and featured a wheelbase of about 278 cm 34.3 Silver-cadmium batteries
overall. Basically, the car was designed as a drag-
ster. The engineering that went into the design of the Applications for primary silver-cadmium batteries
car produced a very tangible result in that the unique include oceanographic buoys, torpedoes, missiles,
speed control system was later to become part of golf underwater scooters, portable field equipment balloons,
or recreational vehicles manufactured by this com- sonar devices, planetary probes, and various civil and
pany. Electric cars powered by silver-zinc batteries military applications.