Finally found something for my AAA Eneloops.

[etc]

It is a true sign of flasholcoholism when you buy the cells first, then look for a light or a device to fit them...

I've had these AAA Eneloops laying around for months, and I finally got one of these headsets that defeat noise, (think lawnmowers, construction work, etc.)

They use 4AAA cells which amplify normal conversation but turn off all noise that exceeds some decibel level. Cool device.

I was hoping to find some 3AA UV light, but got a 3AA UV light off fleabay..

In any case, the eneloops are great for these devices as they are rarely used.

 

[h2xblive]

Oh yeah

I use the AAA Eneloops in my calculator which I probably use once a week.

 

[paulr]

NiMH icells aren't great in 3 cell led lights, because of their low voltage.

The Fenix L0D CE is a wonderful user of eneloops though. Its high power setting makes the rechageability worthwhile.

 

[etc]

> The Fenix L0D CE is a wonderful user of eneloops though. Its high power setting makes the rechageability worthwhile


that is probably the best thing you can do with them.

They are inferior to AA in all ways but one: Size.

 

[Sub_Umbra]

It is a true sign of flasholcoholism when you buy the cells first, then look for a light or a device to fit them...

That's a good way to buy lights -- and firearms, too. I have a 3AAA Brinkman headlight that I need to use twice a month. On NiMH cells it would be dead or near death every time I picked it up. On Eneloops it is a completely different story. I only have to recharge every 45 days or so -- I get three solid uses and I get solid indications when I need to recharge. It doesn't sound like much of a story but the Eneloops have made the light so much more useful -- I'm a believer.

 

[AFAustin]

http://www.candlepowerforums.com/vb/showthread.php?t=157634

Terrific light.

 

[Hans]

Uses for my AAAs? Wel, I currently use AAAs in ...

- an LOD CE, a Peak Matterhorn and various other small lights
- an MP3-player
- a lightweight Garmin GPS
- my trusty old Palm IIIxe

I really, really like devices that use AAAs because they're so small and lightweight.

Hans

 

[Fallingwater]

It is a true sign of flasholcoholism when you buy the cells first, then look for a light or a device to fit them

Not really. It's a sure sign of being a batteryholic, though.

As for me, I have a Palm IIIx. Old, but useful. The normal NiMH cells I used in it always lost maybe 95% of their charge to self-discharge. Then I got two Varta Ready2Use and I haven't had to recharge them since (about four months ago).

I took them out to fill them up yesterday, and they had only lost about 200ma, almost entirely due to use (considering the average draw of the IIIx and how much I use it). I'm impressed.

 

[etc]

Another thing I am considering is a UV light, there are some floating on Ebay. Must be small enough to EDC if you need it.

A 3AAA headlight is another good idea. I don't really *need* it, but it's much lighter than the Apex, and more compact with the cells near the LED.

Problem is, I standardize on AA cells, but got 1 pack of AAA Eneloops cells just in case.

TV remote controls often use AAA cells - but I have neither TV nor remote. Maybe I should get one?

 

[Sub_Umbra]

...Problem is, I standardize on AA cells, but got 1 pack of AAA Eneloops cells just in case.

TV remote controls often use AAA cells - but I have neither TV nor remote. Maybe I should get one?

LOL. Maybe two.

 

[Fallingwater]

TV remote controls often use AAA cells - but I have neither TV nor remote. Maybe I should get one?

Please don't.

 

[Curious_character]

NiMH icells aren't great in 3 cell led lights, because of their low voltage. . .

I disagree. The voltage of an alkaline cell is less than 1.2 volts for most of its discharge time at moderate drains, and the majority of its discharge time at high drain. (An alkaline cell has to be discharged down to around 0.9 volt in order to get most of the energy out.) In contrast, a NiMH cell voltage stays relatively constant at around 1.2 - 1.25 volts over nearly its entire discharge period. So if you put two lights side by side, one with alkaline and one with NiMH, the NiMH light will get a higher voltage and be brighter for a larger portion of the discharge time. The difference is very striking if the discharge rate is high, that is, if the whole discharge takes only an hour or two. The one with alkalines might be brighter initially, but it'll fade below the NiMH light before long. At high rates, it won't take more than a few minutes.

This is true regardless of the number of cells used by the light.

c_c

 

[TorchBoy]

(An alkaline cell has to be discharged down to around 0.9 volt in order to get most of the energy out.)

That's resting voltage, right? Well said, BTW.

 

[Curious_character]

That's resting voltage, right? Well said, BTW.

No, that's voltage under load. It might require discharge to a lower voltage under load, maybe 0.8 volt, if the current is high.

Resting voltage tells very little. If you discharge it down to 0.8 - 0.9 volt under load, the voltage will rebound considerably when the load is disconnected. But the cell will have very little energy left. It will drop again very quickly if the load is reconnected.

Take a look at the graphs at the Energizer data sheet for their AA alkaline cell, for example, to get a better illustration of what I'm talking about.

c_c

 

[Fallingwater]

What load should one connect to an AA or AAA to see its capacity without beating it to death?

 

[TorchBoy]

c_c, the reason I asked is that I remember using Duracell Ultra and I noticed that when they got the to end of their life their resting voltage dropped suddenly to about 0.9V, whereas normal alkalines gradually dropped off (although I'm not sure they got to 0.9V before they were effectively useless).

What load should one connect to an AA or AAA to see its capacity without beating it to death?

The manufacturers test them at 20mA (or 200mA for lithium primary) to get the most out of them. The latest Energizer datasheets have a bar chart of the cell's capacity for various currents and/or power loads. At 500mA their AA has less than half the capacity as at 20mA, while the half capacity point for one of their AAA cells would probably fall at about 250mA, so I suppose that could be called partly beating them to death - a good reason to go with NiMH.

 

[Curious_character]

What load should one connect to an AA or AAA to see its capacity without beating it to death?

The only way to test its capacity is to beat it to death, i.e., completely discharge it and see how much energy came out. With alkaline cells, the capacity can be very different depending on the load. So what you have to do is select a load that matches what your device will be drawing. That will tell you its capacity in that device. A different device which draws a different current (or draws it intermittently rather than constantly) will get a different amount of total energy from the cell -- that is, the cell has a different capacity when presented with the different load.

For LED flashlight applications, realistic testing is probably best done in the light because a regulated light acts like a constant-power load in which the current increases as the voltage decreases. On the bench, the easiest way to simulate this kind of load would probably be to duplicate the flashlight's electronics. Constant current discharge is relatively easy to do, and it gives a pretty good idea of battery capacity under various discharge conditions, but doesn't really fully imitate a constant power discharge. The advantage of a constant current discharge is that it's easily specified and duplicated, so different measurements by different people can easily be compared.

I have some of those cheapo regulator boards on their way from DX. They might be pressed into service as simple approximately constant-power loads. However, I think they'll require more than one cell at a time.

c_c

 

[TorchBoy]

The only way to test its capacity is to beat it to death, i.e., completely discharge it and see how much energy came out.

:laughing: Of course. I must have been thinking of the journey rather than the destination, in how much capacity they have before they're useless.