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.