testing numerous AA batteries sitting around?

Connect a load resistor across the battery and measure the voltage across the resistor with the battery under load. Don't do it for too long or it will make the battery go flat, obviously.

The appropriate load resistor depends on the size of battery. I would suggest maybe 0.5 Ohm or 1 Ohm for an AA.

For an AA cell you could also achieve a similar measurement result using an ammeter provided you know its characteristics (burden resistance and lead resistance, any fuses that are likely to melt).

You could also zip through them unloaded with a DVM and 'whitelist' any that show 1.6V or so, then use the resistor method on the rest. That's how I'd do it, anyway.

The best way I know is the short-circuit current.

Try an amperemeter for test and measure the curent.

Don't last more than a fraction of second for this test.

If it is more than 1A, the cell is OK.

The open circuit voltage measurement is generally always OK before the cell really dies. This tests never give any information about the internal series resistance which is the first symptom of a dying cell.

I have a 1.25V 0.25A MES incandescent bulb. It fits in a simple holder made of heavy galvanised wire wound into a spiral that the bulb screws into, with an extension of caliper shape that connects to either AA or AAA batteries.

The test takes 2 seconds per battery.

If the bulb lights strongly the battery is worth a second chance...

Mike.

For small batteries I test the short-circuit current. New batteries are in the order of 2-10 amps, old ones 0 to ~100 milliamps. Very useful when you compare old- with new battery. Dont try this on big ones!!!!!

Or just buy a really cheap voltmeter from Harbor Freight. Mine cost $6.00 and HAS a loaded battery test function with the milliamp reading to be expected for a good battery right on the case.

I like them as cheap disposable meters but never use them on high voltage other than the simplest tests and then with great caution as they obviously aren't built with much or any real safety features.

I did not think anyone bought those meters as they are usually 'free'. I have 3 of them now. Not too sure how well they will hold up, but I did check them with my Fluke meter and they seem to be accurate enough for general testing. They do have one adjustment inside,but I did not see the need to try and get them any closer.

As with you , I don't think I would use them on anything other than some low voltage stuff. Maybe on the 240 volt around the house, but not too sure about that. I know I would not use them on the 480 volt 3 phase stuff at work that had about 600 amp fuses in it.

** Does not look that bad:

It lacks low AC volt scales and the plugs are not fully shrouded.

The transistor tester socket is a known hazard and I cannot see if battery access requires the use of a tool, much safer if it does.

The battery test function is almost useless, 4mA load on a AAA or larger cell tell you nothing - particularly if it is rechargeable.

... Phil

The plugs are fully enclosed once they are plugged into the meter. To get to the battery you have to remove 2 small screws and the whole back comes off the meter. Yea, 4 ma might load a battery if it is almost dead, but it is not much of a load to tell about the condition of the batteries. Not sure how long they will last, but for free, you can get lots of them if you do buy anything at HF. I have some around the house just to keep from going and getting my good meters if I want a quick check on some light bulbs or something like that. Just as I keep a few other tools around different parts of the house and in the cars.

I use the HF meters because it's easy. For other batteries like the CR2032 and LR44 I've written the new values on the meter.

Now I also date AA batteries when they are installed and write MT (empty) when they are dead. Then stored and recycled under the battery category. Multiple coin cells generally stay in a tiny 3" x 4" zip lock when re-cycled.

** Well yeah, but the shock hazard occurs when handling a plug - trying to put into the meter - when the tip end is attached to a source of high voltage. ** Excellent - batteries are shock hazards if they can become exposed by mere finger pressure or a bump.

The other common DMM hazard is having a non-fused high amps range - if connected across a source of high energy, the leads may explode. Such sources include car batteries and high current AC supplies.

.... Phil

I can't imagine myself attaching a lead to a high voltage source before it is attached to a meter. Or switching the meter connection after it's attached. Maybe it's something one starts doing when the plugs are fully enclosed.

Bob

** But you can imagine the plug coming out of the meter unintentionally, then being replaced while "hot" or touching ground/chassis and causing a massive short. ** Shrouded plugs make it safe to leave probes attached to a high voltage or high current source.

Been a standard feature of any decent DMM for decades now.

.... Phil

then

ve

Based on a sample of one, that is extremely unlikely. The shroud on the pl ug fits very tightly in the case, and there is additional friction from the banana plug. Even if you snagged the meter, you will probably pull the pr obes out ot the CUT before the plugs come out of the meter.

BTW, the one significant flaw in my HF meter is that it does not have a low

-battery indicator. The calibration seems very good with fresh batteries, but gets very bad when the batteries are weak.

** Pal - you need a bigger sample.

** Fit tightness becomes irrelevant when the plug is shrouded.

Hate to think of someone's life or eyesight depending on it.

** It is important to believe in " Murphy's Law" when discussing safety.

It can happen, so sooner or later - it will.

.... Phil