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AAA Battery |
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The AAA batteries are smaller companions to the well known AA batteries. AAA batteries are often used in small electronic equipment, such as digital cameras and TV and stereo remote controls. AAA batteries have become increasingly popular during the last years and there is a definite trend towards the use of small AAA batteries in appliances instead of large AA batteries. The AAA battery is much more suitable in a world where electronic appliances become smaller and smaller each year, not to mention more efficient and less energy-wasting. The AAA battery is also called a LR03 according to the International Electrotechnical Commission (IEC) standard and 24A according to the American National Standards Institute (ANSI). It is also called AM4 battery, HP16, UM4 and simply “micro” or “micro battery”. The AAA battery is 44.5 mm long and has a diameter of 10.5 mm. This can be compared with the AA battery that is 50 mm long and has a diameter of 14.2 mm. They are both cylindrical and the output is 1.5 Volts. An AAA battery weighs no more than 11.5 grams which makes is extra suitable in electrical appliances where the battery weight has a considerable impact on the total weight of the device. The output of an alkaline AAA battery is 900 to 1,155 mA h, which equals 3240 to 4158 coulombs. Modern nickel metal hydride batteries of AAA size store around 800 mA h and have an output of 1.2 Volts. In a technical sense, the AAA battery is not really a battery. Strictly speaking, an electrical battery is a device that consists of many similar cells connected together, in order to create or store electrical energy. An electrical cell consists of only one electrical unit. Since the AAA battery does not include several cells connected together, it is not a battery, it is a cell. In everyday language however, the AAA cell is known as the AAA battery. A car battery on the other hand, is a true battery. Car batteries consist of several cells connected in series. How much charge an AAA battery can store is commonly measured in ampere hours. The commonly used abbreviation “mA h” means milliampere hour. If an AAA battery would be capable of proving the equipment with one ampere of current during one single hour, it would have a so called “real world capacity” of 1 ampere hour. (One ampere hour equals 3600 coulombs.) An AAA battery capable of providing the equipment with 10 ampere during 10 hours would accordingly be labelled 100 Ah, but the battery manufacturers have chosen to use a special system when they label their batteries and a 100 Ah rated battery will therefore in reality seldom provide 10 ampere for 10 hours. Battery producers have agreed on a standard method to determine which rating a battery should be given. This rating is based on battery tests made during 20 hours or more with a discharge rate of 5 percent (1/20) of the expected capacity of the battery per hour. This means that a 100 ampere hour battery can provid e 5 ampere during 20 hours, which is not quite the same as providing 10 ampere during 10 hours even though the total sum adds up. The efficiency of an AAA battery, and of all other similar batteries such as AA, will vary between different discharge rates. An AAA battery discharging 5% each hour will deliver the energy more efficiently than it would at a higher discharge rate, e.g. 10 % per hours as in the example above. To calculate the five percent discharge rate of an AAA battery you take the ampere hours stated by the producer and divide them with 20. The five percent discharge rate of an AAA battery labelled 1000 mA h should therefore be calculated as 1000 mA h / 20 h = 50 mA. |