True 1.5v AA and AAA batteries

[gnappi]

I've been off of commercial pre-charged batteries whenever possible with the exception of AA and AAA batteries. I found that 1.25 volt cells do not work in a number of small devices I have (pulse oximeter, label maker, toothbrush etc.) and I've wanted to get re-chargeable substitutes since forever.

Recently I tried buying eight EBL AAA "1.5" volt rechargeable batteries off Ebay and they were too weird to be of use. They "charged" to 4.6 volts, and afterward read less than 1 volt in my DMM and failed to work.

So I'm on the hunt for a brand that can actually replace the reliable "copper top" batteries I now am forced to use. Has anyone here found anything that works?

 

[ilikeguns40]

I’ve always used Eneloop AA and AAA batteries.

The EBL you got off eBay were more than likely junk

Strange 1.2v won’t work for your devices

Try these Epoch 1.5v

 

[NiOOH]

This has been discussed here. If you want a spot on 1.5 V during the whole discharge, get regulated LiIon AAs.

 

[fivemega]

Fully recharged 1.5 V Li-ion regulated Li-ion AAs have voltage of 1.5 volts WITHOUT LOAD.
Under load of about 1 Amp, voltage drops to about 1.2 volt.
I still think Eneloops should work fine for your application.

 

[NiOOH]

Fully recharged 1.5 V Li-ion regulated Li-ion AAs have voltage of 1.5 volts WITHOUT LOAD.
Under load of about 1 Amp, voltage drops to about 1.2 volt.
I still think Eneloops should work fine for your application.

That's not true. The batteries are regulated and keep constant 1.5 V under load right up to their max. current limit.

 

[hamhanded]

That's not true. The batteries are regulated and keep constant 1.5 V under load right up to their max. current limit.

Have you tested this with some? Which brand? I’ve been using fivemega’s advice on all things voltage related for some time now; it’s possible some brands behave differently.

 

[NiOOH]

Have you tested this with some? Which brand? I’ve been using fivemega’s advice on all things voltage related for some time now; it’s possible some brands behave differently.

Yes, I have with XTAR, but IFAIK all work the same way. This is the point of the stabilized, regulated output (same as in power banks). The advantage is obvious. The disadvantage is that battery indicators become useless, since they read full charge until the very end. I think I measured something like 1.48 V @ the max supported 2 A load. Above this, the protection circuit just kicks in, but until then they are nearly flat (1.50-1.48 V). No Eneloop will read even close to this at 2 A.
Here is a review on another brand: https://ripitapart.com/2015/06/17/performance-analysisreview-of-kentli-ph5-li-ion-1-5v-aa-battery/

 

[fivemega]

The batteries are regulated and keep constant 1.5 V under load right up to their max. current limit.

That's not true.

 

[NiOOH]

That's not true.

I shared my measurements and gave a link to measurements by others. You give only your (wrong) opinion. If you have any proof, please share. Otherwise, it's pointless.

 

[alpg88]

I have tried few different brands, if you can call them brands, i did not measure voltage drop under load, but what i did notice very high self discharge rate for about half of cells, or even more, some died after only dozens of cycles, so no consistency whatsoever, but it was several years ago, yesterday i ordered 4 different kinds on ebay, pretty much every kind ebay had, i will test them again and see if they improved in any way. i do like the idea a lot, but so far execution was so so, at best.

 

[NiOOH]

The only brand I've used was XTAR. Used them for several cycles before giving them to a family member that uses them now (approx 1 year later). No complains about high self discharge or anything else. I guess different brands use different quality cells and electronics. XTAR are known to make (or brand) decent quality products. Based on my experience, I can recommend them.
Then again, if you don't need the constant 1.5 V these supply, there isn't much point of using them. They are more expensive than Eneloops and require a dedicated charger or USB charging. Also, they are limited to a max discharge current of 2 A, and their discharge capacity drops at high loads. Some devices like camera flashes or mech. toys may require a bit more.