Rechargeable AA & AAA batteries are only 1.2V while the non-rechargeable ones are 1.5 v. Why is that?
I have found rechargeable to be be basically useless.
Many devices think they are weak when fully charged.

I googled it and got the tecno babble.
I guess my real question why do they even bother to make them?

quote:

Originally posted by gjgalligan:
Rechargeable AA & AAA batteries are only 1.2V while the non-rechargeable ones are 1.5 v. Why is that?

It's the nature of NiMH battery chemistry. That's all I know.

quote:

Originally posted by gjgalligan:
I have found rechargeable to be be basically useless.

Rechargeable NiMH (Eneloop and Energizer) and Lithium (primary) AA and AAA cells are all I use anymore. I never buy alkaleaks and often set any that come with products aside.

I've yet to have had any device in which I've wanted to use the rechargeable batteries balk at them.

Agreed, I've gone 100% to Eneloops for past 7+ years now for almost everything. Only exceptions are 3V, 9V and a couple things where they don't work well like some little decorative fake candles, etc.

quote:

Originally posted by ensigmatic:

I've yet to have had any device in which I've wanted to use the rechargeable batteries balk at them.

Our Blink cameras do not like rechargeables; they want Lithium primaries.

I have flashlights that produce a much stronger light with 1.5v then with 1.2v.
Small flashlights was my primary reason for getting rechargeable but I guess I got burned on that thought!

I have been meaning to buy some of these

https://www.amazon.com/Lithium...a-2338229125831&th=1

Li technology with an on-board regulator to bring it to 1.5V

no first hand experience, yet, but the 2600mwh is on par for an AA. The other advantage is 1.5V is pretty much held constant until they are pretty much dead, which may be good or bad, depending.

The Eneloop AA batteries read on a multimeter around 1.55V after being charged. These are all at least five year old batteries.

Rechageables for almost everthing here, even my Surefires. Only one device (a labelmaker) that needs to be fed alkies.

1.5v and 1.2v are nominal voltages. AA/AAA batteries don't provide a constant output.

For example, see the below testing charts.

The 1.5v alkaline AA batteries start out around 1.5v, but fairly quickly start to trend downwards and drop to below 1.2v within the first 10-30 minutes and continuing to trend downward in output. Most of their lifespan is spent providing between 0.8v-1.2v.

Whereas the 1.2v NiMH rechargeable AA batteries also start out around 1.5v before even more quickly dropping within 5-10 minutes of use to a fairly steady 1.2v-1.3v, before eventually a sharp dropoff to below 1v at the very end. They spend most of their lifespan providing that fairly steady ~1.2v.

So 1.5v is the maximum for the 1.5v alkaline battery not the average, whereas 1.2v is the average for the 1.2v NiMH not the maximum.

And despite the 1.2v rechargeable NiMH having a lower voltage marked on its packaging, its overall average voltage output over the life of the battery is higher and more steady than the 1.5v non-rechargeable alkaline. The larger number on the package isn't always the better/more powerful one...

In the same vein, some cordless power tools are marked as "20v" while other are marked as "18v", despite them having the same battery output. Both "20v" and "18v" batteries start around 20v when fully charged before quickly dropping and spending most of their life around 18v. So the "20v" cordless tools aren't 10% more powerful or longer-lived than the "18v" tools, though the manufacturers likely want you to think that. It's just a marketing game of labeling them with voltage maximum vs. voltage average.

Sort of off-topic, but the Alkaline 9vs in my safe lock die within weeks, anybody have a source for 9v rechargeables, or Lithium 9v cell packs?

quote:

Originally posted by architect:
Sort of off-topic, but the Alkaline 9vs in my safe lock die within weeks, anybody have a source for 9v rechargeables, or Lithium 9v cell packs?

I get mine from Amazon; normally the Tenergy brand, but there are plenty of other options.

https://www.amazon.com/s?k=lithium+9v+battery

quote:

Originally posted by architect:
Sort of off-topic, but the Alkaline 9vs in my safe lock die within weeks, ...

That doesn't seem right.

Are you opening/closing the thing several times/day or something?

I've only had to replace the battery in mine once in the nearly five years I've had it—and that was the original battery that came with the lock.

Mind you: It's an S&G Titan D-Drive. I doubt the little solenoid they have in there to withdraw the little internal "bolt" draws much current.

My lock is powered by 4 AA alkaline batteries, and they get changed out every 4 years or so. Not sure how an electronic lock could drain a 9V in only a few weeks unless there is something wrong with it! I would try the lithium batteries I mentioned above before giving up on that lock though as 9V batts have a much lower capacity rating than equivalent AA batteries do...

I find the Eneloop AA to be fantastic batteries for mid to high drain devices. We use Eneloops in the XBOX controllers because those eat batteries quickly. I've changed everything except battery toothbrushes to Eneloop. I also number them in sets so they're always paired together and wear together. They aren't has high amp hour as some other brands.

quote:

Originally posted by architect:
Sort of off-topic, but the Alkaline 9vs in my safe lock die within weeks, anybody have a source for 9v rechargeables, or Lithium 9v cell packs?

Mine eats batteries as well. Canon Safari series
I keep the battery on top of the safe & install when I need to open it.
No quick access items in there, so it's manageable for now.

I bought a used Fluke multimeter. It ate 9-volt batteries faster than I could replace them. I sent the meter to Fluke, they found some corrosion on the PC board and replaced it (no charge). Batteries now last for well over a year.