As you read the following. Keep in mind, the information is not intended to be a product endorsement but more of a product test. In doing so, I have described the most common methods of testing common batteries used in the home, batteries found in flashlights, remote control devices, smoke detectors, etc. All batteries tested were of the alkaline type (non-rechargeable). I utilized an inexpensive CENTECH digital multi-meter ($9.99) and a dedicated ZTS pulse load multi-battery tester ($42.00). Batteries tested were AAA, AA, C, D and 9 volt.
Type of test
Drop test- This test is simple with no equip. required. Holding the battery by the positive end (+) drop the battery onto a table from about 2 inches height. If the battery bounces and falls over it is bad. If the battery stays upright, it’s good. I know this sounds crazy, but it works most of the time. This test works with AAA, AA, C, D and 9 volt batteries. Why does this work, leave it to say it involves the hydrogen gas inside the battery. Pros: no equipment needed. Cons: Does not tell you how much battery life is left. This test does not necessarily work on all brands of batteries. Do not use this test with anything but an alkaline battery.
Test Using - CENTECH multi-meter. Test “AA” 1.5-volt battery. With the power switch on, set the function knob to DCV “20”. Place the red probe (+) to the positive end of the battery and the black probe (-) to the negative end. Read the digital readout. As a rule of thumb, a reading of: 1.35v is good, 1.2v is ok, and 1.0v, the battery should be discarded.
Test Using – ZTS pulse load multi battery tester. Test, same “AA” battery. Turn power switch on. Place the + end of the battery to the nipple marked AA 1.5v alkaline. Hold the black probe to the negative end of the battery. The lights on the meter marked 20%/40%/60%/80% and 100% will light in sequential order stopping at the proper level of charge.
Although there is a substantial difference in price, both meters performed flawlessly. The ZTS is more compact and easier to use in testing small household batteries. The ZTS is a small battery tester with dedicated marked areas with nipples for placing different batteries types such as alkaline, NIMH (nickel metal hydride rechargeable), Lithium and Lithium-ion rechargeable batteries. The CENTECH digital meter will perform all the above test plus check for AC voltage, resistance (ohms), and amperage in a circuit if you want to do more than just test small batteries. There are many small battery testers on the market. My advice, before you invest in a small battery tester, read customer reviews, and then make your purchase.