battery issue in H501 (W as well as R version)

[axd]

I've got here two slightly used AA batteries:

• Duracell Ultra, "Mar. 2012", 1.278 V
• VARTA Alkaline, "Sep 2001", 1.329 V

While the VARTA battery has higher voltage, it won't power a ZebraLight H501W ? (Same issue in the red version.)

Unfortunately, I have no other single-AA flashlight to check this. Maybe it has to do with amperes rather than voltage (the VARTA cell is much older too) - in which case I wonder how I can measure this with a basic meter.

-alex-

 

[NutSAK]

Those are low readings for the open-circuit voltage of an alkaline cell. When in use and under load, the voltage in those cells could sag below the threshold required to power your headlamp.

Open-circuit voltage (voltage without an applied load) is not an accurate way to measure remaining capacity in an alkaline cell.

 

[Ragiska]

"slightly" used? try 99% dead. hell, the one is close to being 15 years old.

 

[McAllan]

Sometimes I do come by some 10 year old cells expired long ago which works OK (just don't leave them in because of leak danger).

But otherwise yes. You can't measure an alkaline without load to get a great idea of voltage.
Buy a cheap battery tester like this one. They aren't perfect but much better at getting an idea of how much power is left in alkalines since they load the cell while measuring.
A tester like the one shown should be widely available in practically every super market. Of course the more fancy ones are better but for alkalines the one shown is way better than a simple unloaded voltage reading.

 

[axd]

<>
Buy a cheap battery tester like this one. They aren't perfect but much better at getting an idea of how much power is left in alkalines since they load the cell while measuring.
A tester like the one shown should be widely available in practically every super market. Of course the more fancy ones are better but for alkalines the one shown is way better than a simple unloaded voltage reading.

Thanks for the input, I was suspecting this and it's now my next step. I will also need it because I'm measuring current drains in a small project here.

(And I've started going through battery university too.)

-alex-