Gardner Bender GBT-500A Analog 1.5 V Button Cell/22.5 Photo/AA/AAA/12 V/9 V/Lantern Cells & More, Leads Battery Tester,14 Battery Range, Black

This is hands down the best and only full function all battery tester. With an analog read out, battery contacts on device, coin batteries probes etc you can't get better. You can test alkaline as well as rechargeables. I had one of these for almost 20 years and never let me down. I lost it and was so happy when I was able to find the same model about the same price from back when I got the first I had. I would say if you do battery testing, especially rechargeable, alkaline etc you owe it to yourself to purchase one of these and always know an exact amount of juice left. 500 star rating.

Nice...works great on all batteries. Tests under load.Great price.

This one is very good for the price. It does many types of alkaline, buttons, even lithium. Some reviewers questioned if it is a real load tester. I found the circuit diagram on the internet and can put this question to rest. It has an array of internal resistors that are used to load each type of battery. I also verified it by checking the current during test. There is a small current flow, so it is not just taking open circuit voltage. But of course, the load has to be small or else it would drain the battery. The bonus, no battery required for operation.

I ordered this version after losing patience with a pocket-sized tester at almost half the price. Compared to the cheap tester, this one is more responsive, more accurate, easier to read. Still it's conspicuously smaller than the one with the identical face and features that I purchased 15 years ago. Particularly puzzling is the button-cell holder, which is too small for my 2032's and too big for my smaller button cells. For the quickest, easiest, best results place your battery on the negative contact post and the red wire on the positive end of the battery. There's rarely any need to use the black (neg) wire.

Edited 12/10/15 to fix some typos. Thanks for kind comments!Edited 12/12/20 as some reviewers claimed this doesn't test under load. It does! Turns out they posted to the wrong device! I also added a small information bit to help some readers better understand a few electrical terms I use.REVIEWThis is a very nice analog tester. It has a quality feel, and test leads that appear likely to hold up to long use. I've bought 7 so far, 3 for me and the others as little gifts. (I dont accept payments for reviews).It handles a very wide range of batteries. I am very pleased with mine, especially at its low price. There are incredibly cheap testers available on Amazon, but they lack the ability to appropriately load the battery being tested. Here's what I mean.A battery tester works by putting a load on a battery and measuring the voltage at the battery terminals. The reason is that this voltage, measured with a good voltmeter that draws almost no current, changes little as the battery wears out. What does change is that the battery's internal resistance increases, which wastes energy, and the amount of chemicals available to generate current decreases. By putting a load on the battery, the meter can see whether the battery is still able to do its job.This tester has 9 switch positions which set it to select a reasonable load and voltage range for a battery type, giving you a much more reliable test than a plain voltmeter can. See the table below. Notice that there are 3 different current drain settings for 1.5 V batteries. These are chosen to roughly match their normal use; 1 mA for tiny button cells used for watches, 50 mA for AAA batteries, used for remote controls, and 150 mA for AA or bigger C and D batteries used for flashlights, etc. If a tester draws too much current, it can deplete the battery just by testing it, and a battery tested at too little load may test Good yet not work in your device.Understanding this, this tester is still very useful in sorting through batteries, even if your device uses an unusually high or low amount of current. Digital cameras, for example, draw a lot of current for a few seconds when they are recharging their flashes; the internal resistance of ordinary batteries wastes power, giving them short useful lives. Yet they can last for years in a low-drain steady application like a clock. So you need to use your judgement. If you find that batteries test good but only move the tester needle a little above the bottom of the green range will not work in your device, yet you might be able to use them in something else for a while.SPECIFICATIONS (from supplied manual)Range..............................Load Current.........Minimum Voltage for......................................Drain...................GOOD IndicationButton Cell 1.5V.................1 mA...................1.125V +/- 0.0WAAA-N-1.5V.......................50 mA.................1.125V +/- 0.09VAA-C-D-1.5V.....................150 mA................1.125V +/- 0.09VLithium 3V..........................1 mA..................2.25V +/- 0.18V6V...................................10 mA.................4.50V +/- 0.36V9V...................................10 mA.................6.75V +/- 0.54V12V.................................10 mA..................9.00V +/-0.72V15V.................................10 mA..................11.25V +/- 0.90V22.5V...............................10 mA.................16.875V +/- 1.35VSorry about the formatting. Some Amazon doofus decided it would be nice to strip out all my tabs and extra spaces. Try landscape view if you can.On second thought, maybe I should not have called her a doofus. I am told Amazons are pretty tough ladies!Maybe they just wanted me to use up all my punctuation marks so I'd have to order a new box of periods! :-)

The Gradner Bender GBT-500A battery tester was ordered after discovering our old tester was giving false readings, with good batteries being discarded. Looking for a simple version of a tester, this one worked just fine, has a little kick stand for propping it up, leads, weight and size are standard, with wires measuring approximately 24" in length. No batteries are required.The overall design is good, except it would be nice to have a digital readout. For our purposes this one is just fine indicating if a battery is in the green zone, which is good or in the red zone, and needs replacing. This is a time saver.Their product line on Amazon offers a variety of items of interest as well, and appear to be reasonably priced.

I've been wanting a tester that would test all kinds but wow! I have no idea just how many kinds there were! Great tester with accurate readings. No instruction manual included