Testing Batteries  : purpose carbon-zinc batteries but last about seven or eight times as long. AI~.c batteries have a high capacity, are better at high and low temperatures, and r: long shelf life.
Nickel-cadmium batteries are sold as “ni-cds” batteries. Unlike the : batteries mentioned above, they are rechargeable batteries. When they run c: they can be put into a battery recharger and restored to life. Ni-cds cost abo..: times more than general-purpose carbon-zinc batteries and don’t last as 10-, alkaline batteries. However, they can be reused dozens of times.
The batteries above are the most common types for general use. Hov. ~ there are many other types as well. Mercuric-oxide (”mercury”) batteries are _ in electronic watches, calculators, and hearing aids. They are the “button” t\ =_ batteries about the size of a large, thick coat button.
Silver-oxide batteries are also button cells. They are also used in some: of watches.Lithium-manganese (”lithium”) batteries are used to power watches liquid crystal displays (the gray orgreen type of digital display). They have = button shape.Zinc-air batteries are used in pagers, hearing aids, and personal me: electronics. They are a fatter button battery.

A Little More About Batteries

Batteries store electrical energy. Generally, the larger the battery size more energy that can be stored. Batteries supply electrical current at a cevoltage. Current can be thought of as being similar to water flowing throi. ~ hose. Voltage can be thought of as the water pressure forcing current throug : hose. Some devices, such as flashlights and portable tape recorders, req; . great deal of current and run down batteries quickly. Other devices, sueremote controls for televisions and video cassette recorders, require ver, current and do not run down batteries very quickly at all.
In addition to material used and physical size, batteries are rated in vo .: and the amount of energy they store. The voltage of a battery is the amou “force” required to push the current through a device. Common voltages arC’ volts (flashlight cells), 6 volts (lantern batteries), 9 volts (transistor radios anc . equipment), and 12 volts (camcorders). A higher voltage battery isn’t betterjust designed to work with a certain device at that voltage. Replace batteries. ones of the same voltage.
The amount of energy stored is often not given for common batteries, sue A, AA, B, C, and D cells. Batteries for high-current requirements, such as carr : ders, are sometimes rated in mAh - milliampere-hours. The higherthis rating longer the battery wi II last. A mAh rating of 2000 mAh means that the batter. last twice as long as one with a rating of 1000 2mAh.

Posted: July 18th, 2007 under Batteries.
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Batteries are found in watches/ calculators/ hearing aids/ cameras/ flashlights/ tv remote controls/ camcorders/ portable telephones, computers/ portable televisions, rad ios, tape recorders, smoke detectors/ and hundreds of other items. You don’t have to be an electrical engineer to test batteries - no knowledge of electricity is really required. Also, there’s no shock hazard with batteries found in consumer products. You can handle 1.5-,6-, and 9-volt batteries with your bare hands. It’s only when special-purpose batteries with voltage ratings over 30 or 40 volts are involved that you have to be concerned about shocks.

Precautions to observe with batteries are these:

• Never throw batteries into a fire. Extreme heat might cause them to explode .
• Watch for occasional leakage of battery acid. This is no longer a major problem.
However, if you do encounter slight leakage, wash your hands quickly and thoroughly and take care not to get the material into your eyes.

Types of Satteries

There are four very common types of batteries in general use: carbon-zinc/ zinc-chloride/ alkaline, and nickel-cadmium batteries. Their life and cost increase in that order.
Carbon-zinc batteries are usually the lowest-priced batteries to be sold in stores. They are not good for extreme heat or cold and don’t have a long shelf life. (Shelf I ife is the time batteries stay on the shelves before they are used.) They should be used in equipment that does not require a great deal of energy. They are poor for high-current devices that use light bulbs or motors but fine for flashlight use. If your inexpensive batteries run down quickly, it might pay to invest in a better grade.

Zinc-chloride batteries are usually sold as “Heavy Duty” batteries. They cost about 50% percent more than the least expensive batteries. On the other hand, they last about 50% longer than the least expensive grade and are better at low temperatures.
A/kal ine batteries are the best grade of throw-away batteries. They are usually sold as “Alkaline” batteries. They cost about three times more than general.

Posted: July 18th, 2007 under Batteries.
Comments: none