![]() ![]() Heres how it works: First, we measured 750 milliamperes (ma) of lantern current using a halogen bulb to establish our target load. (The voltage measurements were used to extrapolate when a battery was at 3V if we were not present to witness the exact time.) Here, we squeezed them out like a sponge to measure their capacity while we periodically took voltage measurements to gauge their usefulness. The lantern battery test fixture differs although it still employs the clock. The second life is usually short-no more than a minute when we tried it-and of no useful significance to the user. Also, batteries, after a certain amount of rest, seem to be able to rise from the dead temporarily. It may run a low-voltage toy for a while but we don’t care. At 1.05V, flashlights are dim (but usable), portable radios are scratchy, portable TVs finicky, and we consider the battery dead. The result yields an accurate capacity measurement of a 1.5V battery between its start voltage and its fail voltage (1.05V). Our technique of applying a continuous load perhaps shortened the lives of our test batteries, but all were subjected to the exact same conditions. It should be noted, as most who have had any experience with flashlight batteries are aware, that batteries last longer when used intermittently. Last time we reported it at 1.1V when it is, in fact, 1.05V. Here, the weight leverage was eliminated when the clock attempts to move the hands from 6 hours to 12 hours and this resulted in a more precise measurement of the cut-off voltage. What we did differently this time was to operate the clock on its back. A quartz clock keeps good time over a wide voltage range until it stops at consistently the same voltage point. (We varied loads this time to verify performances from moderate to heavy).ģ. Each cell is subjected to the exact same load in any given test. Anybody can duplicate our work with a couple of clip leads.Ģ. Although weve been criticized for using this ridiculously simple fixture, it has some definite virtues:ġ. Like last time, we configured a simple test fixture comprised of a kitchen quartz clock, a load, and a place to install a battery. Lastly, both Energizer and Duracell have installed gas gauges on their cells to tell us how good the battery is, so we decided to see how well these devices perform. In fact, Duracell told us each size is designed by a different team of personnel. This time, we tested all three sizes to see if that is the case (it isn’t). ![]() We also assumed last time that D cell performance should reflect the performance of any size battery made by a given manufacturer. Although that position has not changed much, we now learn that 75% of battery sales are in the AA/AAA families that power everything from electronics to toys. The last time we tested alkaline batteries (June 15 and November 15, 1995), we reported that Duracell dominated the market, with Energizer and Rayovac a distant second and third, followed by the unadvertised generics. ![]()
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