I’m currently writing a 2024 buying guide for chargers and batteries aimed at night photographers. I’m interested to know everyone else’s opinions on rechargeable 1.5V Li-ion AA and AAA batteries?
My thoughts…
The versions with integrated charging ports are all from “unknown” manufacturers. The charging port decreases capacity due to size and adds an additional point of failure. Avoid from me, unless anyone has had good experiences?
Versions that need dedicated chargers. Other than XTAR, all “unknown” manufacturers. Most use confusing mWh instead of mAh. I would only recommend XTARs options. Again, any good experience with other manufacturers?
My opinion - not worth buying, unless some very specific application exists.
Why? Because they have some serious issues:
Self-discharge. DC-DC converter has to be always on which creates significant parasitic drain. This makes them very bad for low power applications like a multimeter or TV remote, for example.
Limited output. Small DC-DC converter can only supply very limited current without overheating, this makes them bad to unusable for high power applications. Flashlights are probably here.
DC-DC converter creates noise, and since many battery powered devices were designed with perfectly stable power in mind this can create issues, especially for measuring equipment and such.
Those without USB also require special charger, which will be different for each manufacturer, increasing cost and adding typical “proprietary battery” caveats.
Regulated output regardless of charge state, so any built in battery indication in devices does not work and device simply suddenly dies. There are attempts to mitigate this, but they are… less than perfect.
Capacity is not great, not only they use smaller cell, but also DC-Dc converter means losses.
And then… there is Ni-MH. Modern LSD Ni-Mh does not have any of said issues, has self discharge which is lower than even bare li-ion cell would have, are more stable and have capacity similar to bare li-ion cell of the same size.
The only case where li-ion+DC-DC might be useful is when specific device does not like lower voltage Ni-Mh has and at the same time fits into the limitations well and requires relatively high current. One example would be some game controllers. For low power device which do not like low voltage lithium primaries will, almost certainly, make more sense.
In all my AAA and AA flashlights, I use Eneloop instead of Alkaline.
I see no advantage to using 1.5V LiIon instead of Eneloop, for my flashlights.
I have a remote control for an airconditioner, that does not work on Eneloop. So I use Alkaline. The remote works for over a year on a pair of AAA alkaline.
Im not motivated to buy in to the 1.5V LiIon batteries, just to replace two Alkaline batteries, once a year.
I have a couple of emergency flashlights loaded w Energizer Ultimate Lithium. Because I want the long shelf life, and broad temperature tolerance.
I dont think the 1.5V LiIon would hold charge for as long as the Ultimate Lithium.
So for me, 1.5V wont replace Eneloop, nor Ultimate Lithium.
And I do not use enough Alkaline to make me want to buy 1.5V LiIon.
I have about 20 of AAA and AA, from different brands, some are better than others, all have about half the capacity of alkaline, all but one from manufacturers that have little to no reputation, xtar makes them too, the only somewhat known manufacturer. i have their aaa, they run fine in a toy car, not as long as alkalines. recently they came up with aa that they claim have 2500mah capacity, but they do not say at what current it has that capacity. I do not have them long enough to test for self discharge. I would not retire eneloops just yet, unless your device is really not tolerant to lower voltage, they would provide more current and possible lower self discharge. however 1.5v are improving, i tested some few years back and they were pretty bad, these newer ones are better, even no name ones,
I have three different versions of XTAR 1.5V Li-ion AA cells.
White and blue. No indicator for charging.
Green. There’s an indicator light while charging near the top side.
Dark blue. There’s an indicator light near the button top. I think this drops from 1.5V to 1.1V to indicate low voltage.
I have a few chargers that support them:
XTAR BC4 with LED indicators.
XTAR LC4 (old version, like BC4)
XTAR MX4 (new, reviewing)
Use cases:
Toys involving motors that need a constant voltage (e.g. trains).
Wireless keyboards. This resolved intermittent Bluetooth dropouts at 3 metres as Ni-MH gradually drops.
Aircon remotes. I can’t see the LCD when NIi-MH drops.
Situations where I wouldn’t use them:
AM radios where there’s too much radio interference.
My teevee remote takes AAs, and using eneloops at 1.2V, first, I can’t see the backlight as it’s hardly lit, and second, range sucks. With the 1.5V Li cells, the backlight is nice and bright, and rather than having to use a sniper-scope to aim precisely at the receiver on the teevee, now I can even aim it at the ceiling, the wall behind me, etc., and have bounce trigger the teevee.
I’ve used them in lights like my Xeno where there’s a visible difference between 1.5V and 1.2V. They’re brightest with the 1.5V Li cells, as alkaleaks drop proportionately in voltage under any load whereas these puppies will struggle as needed to maintain 1.5V no matter what until it’s just too much.
LC displays will look faded as the crystals don’t “twist” as much under lower voltage. My clock/thermometer will work great with fresh alkaleaks but then fades as they age, and will start out “faded” even with fresh eneloops. It’ll be full “brightness” with 1.5V Li cells, even though the RFI will mess with its ability to use the set buttons.
The biggest most badass reason to use them instead of alkaleaks if at all possible is that Li cells won’t crap the bed and ruin the entire device when they do it, like alkaleaks will. If youse want to replace an entire remote, or clock, or whatever, go crazy. Me, I’ll use these Li cells even if I have to charge them monthly vs swapping out alkaleaks after a year. Only I don’t have to charge them monthly as even if they get half (vs a tenth) the lifetime of alkaleaks it’s well worth it.
When you say [night photography] what do you mean more specifically?
As L37 points out the voltage converter can choke output, making them work poorly or not at all in some demanding flash applications.
In my limited tests there is a LOT of variation between the few brands I have tested.
If you mean, simply putting them in generally lighting, their advantage might be keeping the output up, as long as the current requirements aren’t too high for the converter. The downside is reduced capacity compared to NiMh.
my minimag 2aa and zl-h53 work fine with EDL brand 1.5v li ion AA,. thou visually zl runs brighter off duracell optimum,
I also have 6 D cells also EDL i used them in 6cell maglite, but it burns bulbs pretty quick, they do not sag the way alkaline do, i probably need to use 7 cell bulbs with these cells
I wouldn’t call it misleading. It’s the correct way to do it. Mah is incorrect, it’s just become the standard. Since the voltage is different than nimh, it would be incorrect to use mah as they’re not relatable
I get that. OTOH, the way I use them is mAh OUT when I test them. I could just as well use mWh, but mAh is the reference I’ve become accustomed to.
Either way these 1.5v Li almost NEVER EVER come up to their claimed capacity. 2/3 is not unusual, and 1/2 is unfortunately not uncommon, especially with the AAA.
Personally I’d be less disappointed/annoyed if the correct specs were marketed. But…this would sucker less people in that don’t have the tools to test.
Oh, I get that. Don’t have any of these. I would never buy a cell that has any type of electronic circuit on it. I guess except for Olight cells, But that’s only because there are no other options. Eneloops Work for anything that I would need. And I don’t have to worry about current draw with them like I would, with one of these. I do believe I have a couple of XTAR ones coming, but that is only because they are providing them with the review unit of the new MX charger they sent me. But there seems to be a mail delay as I still have not received it.
If they used mwh for all cells it would be fine, but when they use mah for some cells and mwh for others ordinary consumer gets confused, Xtar rates their latest cell in both.
Real capacity depends on current draw, if brands rate it at 50ma draw, than it could be close to rated. but draw at 200, or god forbid 500, you get half
Ahh, so you have noticed some ill-effect(s) likely due to RFI. That’s good to have a confirming data point on (although I’m not ‘happy’ to hear it). Few if any users have mentioned such, and at least one manufacturer seems reluctant to discuss it (or provide specs), although the potential / likelihood of such is rather obvious, and has been one reason I’ve not yet tried any of these cells. Anyway, thanx for confirming that this goes beyond simply the theoretical realm, which does not come as a surprise to me.
Technically, I probably could just stick a cap across the cells to smooth the voltage the doodad sees, but to me that’s just extra leakage current, and probably awkward. Also, no idea if that added cap would cause oscillations by yanking the control-loop to be unstable.