Eneloops are fantastic. I've been using them for 10 years.
They have very low self discharge so you can keep them on the shelf for a year and they will still have 70% charge which is very different to most rechargeable batteries.
They don't leak unlike alkaline batteries and you can run them to 0% charge without damaging them unlike Lion batteries.
The terminal voltage is only 1.2v so there is the occasional thing they don't work well in.
That said my collection of eneloops get much less use than they used to as everything comes with built in lithium batteries and a usb charger nowadays. That is very convenient until the moment the lithium battery dies...
Changing the lithium battery in things sucks. Firstly it's really difficult to get a good one and not a crappy knock off. Secondly modern stuff isn't meant to be repaired. Every time I pick up my kindle I shed a small tear when I see the screen damage I caused changing the battery.
So, I buy stuff with AA or AAA batteries if possible and if I want it to last for more than 3 years.
Designers have a choice in lithium-ion though. 18650 is is pretty large cell but there's 14500 which is AA sized or 10440 which is AAA sized. They make versions with the usual battery "nub" rather than the flat faces for spot welding, and built-in protection circuitry to prevent over-discharging. You probably would want to use ones of a different size than normal 1.5v cells though. A personal favorite of mine is RCR123A/16340.
Even many of the pouch cells come in "standard"-ish sizes. An 803860 is nominally 8.0mm x 38mm x 60mm, but I am seeing more custom sizes recently.
Meanwhile, alkaline batteries can go to hell. You might as well plan on one leaking in the battery compartment. My favorite non-rechargable 1.5V AAs are Li-FeS2, which never leak and have spectacularly low self discharge (especially good for multi-year ultra-low-power projects), but are dammed expensive.
> Designers have a choice in lithium-ion though. 18650 is is pretty large cell but there's 14500 which is AA sized or 10440 which is AAA sized. They make versions with the usual battery "nub" rather than the flat faces for spot welding, and built-in protection circuitry to prevent over-discharging. You probably would want to use ones of a different size than normal 1.5v cells though. A personal favorite of mine is RCR123A/16340.
But other than 18650 you can't expect to find a lot of devices using any particular size.
We should strive for a couple blessed sizes that a lot of devices will stick with, where all cells include a nub and protection circuitry.
I love the 14500 except for its footgun shape. 6 x 14500 is at least 21 volts, which won't play nice with a device that wanted 9 volts. I used to try to keep the 14500s far away from the AAs, but there's no stopping a kid in a hurry who wants to play with a toy or musical instrument.
I've taken the approach of electrical-taping my USB-chargeable 14500s each to a dummy-battery, since the things I put them in have 2 adjacent slots for series AAs. The voltage is still high (3.somethingV instead of 3V) but they seem to work.
>Meanwhile, alkaline batteries can go to hell. You might as well plan on one leaking in the battery compartment.
On the other hand, alkaline batteries never burn your house down.
I also feel like they serve different purposes. Needed for long-term storage and only used in an emergency? (eg, a flashlight for power outages) You're probably better off going with old-fashioned alkaline batteries. Duracell claims they're good for 10 years. Needed for day-to-day usage? Lithium might be better: you can monitor for swelling, the battery recharge-ability is probably more important than any of the downsides that come with lithium ion batteries.
No, there's basically no reason you'd ever want an alkaline battery except cost. For your use case of long-term storage or a rarely used flashlight (e.g. in a car emergency kit), you'd want a Li/FeS2 as the parent poster recommended, also called just a "Lithium" primary (i.e. non-rechargable) cell. They have a longer shelf life, don't leak, hold more energy, can provide a higher discharge current, work over a wider temperature range, and have safety characteristics very similar to alkaline.
> You're probably better off going with old-fashioned alkaline batteries.
Never. They will leak and die. Alkaline cells always end up leaking and dying in my experience, given enough time.
In fact, I do the reverse: If it's something I think will sit for a long time, I make sure to put a rechargeable battery in it. That way, worst case, it's dead—but it won't be destroyed by a leak.
Alkaline has a tendency to leak electrolyte when stored in devices long-term, especially if used intermittently, even more so if the loads are at the upper end of what alkaline can handle as they are in many modern flashlights. The electrolyte is corrosive and often results in a broken device, which is exactly what you don't want in an emergency.
Li-ion's self-discharge is pretty low for a bare unprotected cell, and a flashlight with a mechanical switch consumes no power when off. One must take care to avoid short circuits when handling such a cell, but modern Li-ion flashlights have over-discharge protection, so that's the main safety concern with a single-cell design.
I just worry that the voltage of these is a bit too high, if the device takes 3 or 4 in series. They tend to be around 1.8 volts per cell, significantly higher than a fresh alkaline AA at around 1.6 volts, and even after half the energy is discharged, if the device is off for a long while, the initial voltage for next turn-on creeps all the way back up.
(The price doesn't bother me ... it's worth the much lower chance of leaking than alkaline, if you leave it in a remote or gadget for years. But I've come to think that rechargeable NiMH like eneloops are a better idea due to the voltage.)
I’m visiting some family and I’m a hero for fixing a couple devices that stopped working from alkaline batteries by using a bit of foil paper to overcome the corroded contacts.
Maybe not great in the long run (steel and aluminum don’t like eachother)… maybe I should have put on some grease…
I swab the corroded contacts with white vinegar from the kitchen. It turns the white gunk into a foamy blob, and I assume it etches off enough of the corrosion to restore conductivity. I wipe the foamy part with the dry side of the cotton swab, and the device usually works again.
I started doing this as a kid, reasoning that the white gunk looked like baking soda, which is fun to combine with vinegar, so let's see what happens. I just looked it up, and it appears that the process is legitimate and safe. The vinegar turns potassium carbonate into potassium acetate, also producing carbon dioxide.
The Xbox 360 was the most gamer friendly console (play your open music during games?!?) but one feature i loved was the battery packs. Your controller died? Just swap a pack - two seconds. And the packs could be rechargeable or AA so you could have a bunch of rechargeable AA for a fair price and never get bogged down waiting for anything to charge.
Series X controllers still work this way. Takes standard-ass AA batteries, including rechargeables; or you can buy a bespoke charge pack[1] which actually supports charging while in the controller.
I really wish more devices went this way. In devices these days the thing that will fail first, long before other components, is usually the battery. It seems disingenuous of manufacturers to claim that rechargeable batteries are good for the environment and then ship devices without user replaceable battery packs.
The best thing about Eneloops do not seem to leak. I can just leave them in rarely used electronic devices without worrying. They might discharge, but so far this has never been a problem.
Am I courting disaster by reviving won't-charge pouch cells by just manually running a bit of current through them until they're nonzero volts and then a normal charger will do the rest? So far, in the maybe half dozen times I've tried it (rectangular battery blocks for old digital cameras, the pouch cell inside a long-disused Kobo Reader) it's worked. They charge right up, they don't swell, and they still have decent capacity.
I'm running at the hairy edge and only high quality safety engineering is protecting me here? Or these cells can take a lot more abuse than they're given credit for?
I've thought before that it'd be nice to have some kind of device that would do this in a safe(r) fashion wherein you'd connect the 2 charging leads to the dead battery plus a temp sensor pad and it'd slowly bring the charge up to the minimum required for charging by a regular charger.
Over-discharged Li-ion cells can grow metallic lithium dendrites that result in internal short circuits. Charging them again following over-discharge does create a risk of fire/explosion.
Cool. I have a modern (not smart) body weight scale and it regularly ruins this way at least one of the 3 GP NiMh rechargable AAA batteries I put in it, so I wanted to hear some ideas what could be done with them given they have been through only bunch of charge cycles.
My offshoot rant is that it should be easier hold devices at a longevity charge.
I want some gadget that keeps my essential gear in a long-term maintenance mode. Oscillate it 20-80% or keep it at 50%, whatever is optimal.
Every time I've looked into building something like this it seems like there's no standard reporting of charge level over the wire. I would waste a genie wish on this to have it in the USB spec and widely adopted.
My Xbox 360 controllers are still in use. Meanwhile, I've resigned myself to never using any PlayStation controllers for more than three or four years.
AA and AAA batteries are great. I wish using them weren't considered a negative by many hardware reviewers.
Yeah, I tried fixing the wand controllers for PSVR, ordered batteries from AliExpress. It took an hour to get everything done, and I was constantly scared I'd break something. That was a few years ago. Now they are back to not working; I'm not sure if I can even still get the batteries.
Alkaline batteries only have 1.5V for a short time. In practice, toys are designed to opeerate off of 1V to 1.5V, because Alkalines vary _wildly_ in voltage during use.
NiMH at 1.2V _STAYS_ at 1.2V, even when drawing 1Amp or more (under these conditions, Alkaline would have long dropped below 1V).
EDIT: This is also a problem because "nicer toys" will measure the voltage assuming an Alkaline is "full" at 1.5V and dies at 1.0V. However, NiMH starts at 1.35V, then "plateau" at 1.2V, and stays there for most of its life, before rapidly falling off to 1.0V or .8V like a cliff at the end of its life. So NiMH life "cannot be predicted" by any simple metric.
I had an issue with the original Apple Magic Mouse that would not work correctly with NiMH batteries but work fine with disposable AA. The mouse would be fine for a few days then randomly stop working; using fresh NiMH would revive it again. I assumed it was due to 1.2v vs 1.5v but perhaps that particular mouse (or all Magic Mice) was just bad.
You can now find 1.5V Li-on AA batteries with, and that's a game changer, built-in charger and a type-C port!
I have one in my wireless mouse. If it dies, I change it to a spare and charge it right from my laptop (and the battery that was empty becomes the spare)
I haven't used them, but IIRC they maintain a constant voltage until they're discharged, when it instantly drops to 0. That may be a problem, because if your device has any battery indicator, it will show the battery as full until the end. Nothing will tell you that you need to replace the battery before the device powers off. That's why I decided not to buy them. My mouse knows when my alkaline AA battery is low and gives me a warning.
Came here to post this. I'm 100% agreed with Mr. Geerling.
For a fun challenge try to find a non-built-in-battery arc lighter (eg: candles, grills, etc). When I found one I bought four (think camping/disaster bag... if everything is AA/AAA then having a shelf-stable fire starter is easier/safer than lighter fluid).
For a fun sidebar check out the "Panasonic BQ-CC87AKBBA" which is effectively a combo "in/out" battery charger OR USB battery pack(!). It'll suck in (unfortunately) Micro-USB and charge your AA's, then switch a button and it'll spit that power back out as a battery bank. When I find one like that for USB-C, it's going on my christmas list.
Look up plastic battery holders that hold 8-10 along with a 4x charger and I just swap batteries out and recharge them into that buffer/holding cell. I'll have to look into the Eneloops as I've been working with the Amazon Basics and generally have 1-2 batteries fail out every few months (and am specifically looking for heat-resistant / outdoor applications).
Last one: Lots of cheap solar products have cheap rechargeable AA batteries inside... you can generally open them up and swap the battery out if they're not working any more (and/or potentially scavenge the charging panel if you think about it!).
I believe I have zero Alkaline batteries left in my house and I'm relatively surprised that pretty much everything works fine. If anything, I suspect the only problem is that some devices have an inaccurate account of how dead the batteries are. But I use Eneloops on everything, even things surely not designed at all to run on them. (And I reckon you could probably make more devices work if you really wanted to; adding an additional cell or two in series would surely give you a voltage that's in range, if you can figure out a good way to do it.)
Of course not all rechargable batteries are the same; there are a few different rechargable battery chemistries in the AA form factor. I like Eneloop Pros, though; they've been very reliable for me. I've been using them for years and I've never had to throw one out yet; supposedly they last over a thousand cycles with most of their capacity.
I think I have only one device that uses AA - my central heating's radio thermostat. This thing has caused me untold hassle, which is only partially down to the batteries, but still...
Totally OT, but does anyone have a good link on how the thermostat gets paired with the boiler? I'm thinking of getting replaced and would like to talk to the gas fitter from a vaguely informed point of view.
A weird flipside is things like... the IKEA Zigbee devices. Many of these do not work right at all with 1.5V batteries and basically require rechargables.
I invested a few hundred dollars into Eneloops, but they kept disappearing. Turns out my kids were throwing them away, thinking they were disposable (cry).
I’ve since trained them and rebuilt my stockpile but that was painful, at what was then $2 a cell. (Now $3-4.)
I have a bright label on each saying “Do not dispose”. Hopefully it’s enough to at least get someone’s attention to read or ask further before throwing them out.
I miss the old Rayovac batteries. They had a 10 year no leak guaranty, and it was real. I did get some to leak - I found a box of gear that I know hadn't been opened in 13 years, and even then it was a small leak that wouldn't be hard to clean up.
But Energizer bought the company and changed the formula.
Were the old Rayovac batteries alkaline or zinc-carbon? Zinc-carbon batteries use a "dry cell" chemistry that will never leak, have a low self-discharge rate, and are very cheap to make and buy. You typically find them marketed as "heavy duty." The trade-off with those are that they have a lower energy capacity compared to alkaline.
I use NiMH in almost everything but for things like TV remotes and clocks that sip power AND you can't be arsed to change them all the time, they work great. I buy a pack of 4 at the dollar store.
Fortunately you can get adapters to take 18/20 volt batteries to any other (18 and 20 volt rechargeable are the same cells, but they measure the voltage differently). Likewise most 12v systems have adapters.
There are two issues: some manufactures put more smarts in the battery than others. So never run the battery completely dead which some combinations allow. Never charge the battery with other than the OEM charger.
Don't buy the off-brand batteries (which sometimes are counterfeit that look like the real thing) since they sometimes are not safe.
I have some LiPo-based 1.5V AA and AAA batteries that have USB-C ports built in for charging. The AAA ones claim 1200 mWh (800 mAh) and the AA ones claim 3400 mWh or ~2250 mAh. (I say "claim" because I bought them off some random Amazon shop a few years ago and haven't bothered to actually check.)
I have a considerable backstock of Logitech Anywhere MX (no bloody 2, 3, or 4...) mice in my drawer entirely because they can be powered by 2x AA batteries for months at a time. I like these because when the batteries die, I just swap them out and keep doing work.
I have one of the newer models and when the battery runs out, I have to stop what I am doing and charge the mouse. Yes, you can get through the rest of the day with a quick 5-minute charge but if you're like me, you won't remember to plug in the mouse at the end of the day and will have to repeat the quick-charge multiple times until I finally remember to plug it in overnight (usually by writing a sticky-note). I assume Logitech's answer to this would be: buy a second mouse as a backup!
The only major downside is that these older mice don't do bluetooth and USB Type-A ports are getting more and more rare.
This has greatly informed my decision to always try to buy things that take AA batteries, or at least easily replaceable li-ion batteries (at worst).
I found a Minidisc player that had been in storage for over 10 years, probably closer to 15. Runs off a single AA battery; I'd left it with a Duracell and it was still running.
> It would be faster to leave the batteries in my tools, but over 40 years of sacrificing devices to alkaline cell leakage, it's my habit not to. So far I've never had leakage problems with the eneloops, but old habits die hard.
I've gotten burned by that too, but I just try to remember to take out the batteries before I put something into storage.
BTW, I think the old-style "heavy duty" batteries and lithium AAs don't have a leakage problem. Though lithium AAs are now ridiculously expensive. I think they went from $1 a cell to $2 in cell in a Sam's Club 18-cell bulk back over a couple of years.
A 4-pack of Eneloops was my first ever online purchase in life. I bought them off eBay, scared shitless I'd get scammed or my data stolen (I was very young; the online shopping industry, too). But they happily arrived in my mailboz one day.
They were for a Konica Minolta camera and they lasted surprisingly long. I think I saved about 30-40% of the price of the camera itself in recharging Eneloops, instead of buying new AA batteries every now and then.
Ahh the Sony Walkman. Yes, still useful. I bought one specifically for the AM radio, I use it in conjunction with a radio frequency generator (so old it uses vacuum tubes) to trace wires. Had to tape gauze over the headphones, the foam is long gone.
I'm always surprised that camping, and other outdoorsy, tools (i.e., flashlights, headlamps, satellite communicators, GPS, etc.) are increasingly powered by li-ion batteries. I think it's because there is currently an "ultralight" trend going on in the backpacking world, but it's still very annoying. When I go out, I just make sure everything, except for my Kindle, is powered by AA(A)'s. This way all I need is a dry bag with some extra non-rechargeable batteries, my battery charger, and solar panel.
At https://infinite-battery.com we're making a repairable battery where you can change the cells, because there's no reason your e-bike battery should work differently than your remote control: when batteries are drained, you can change them!
Highly variable based on load and the specific batteries involved. Alkaline will almost always have more capacity for something that takes more than a day of continuous operation to drain the battery, and NiMH will almost always have more for something that takes less than four hours.
Here's a tool you can use to compare different batteries at different loads, graphing voltage vs Amp-hours. The individual battery tests have more detail and graphs of voltage vs Watt-hours, which is often a more useful measurement.
Speaking of which, I really hate those chargers that force you to use two batteries instead of one. I get that it is cheaper to design it that way, but come on.
NiMH chemistry allows for safe overcharging though. If the chemistry allows for it, why not take advantage of it and have cheaper chargers?
The downside is that "save overcharging" only works at very low charging rates. That's why the double-charger designs all have 10+ hour charge times (mine actually has a 20-hour charge time).
But in practice? Its cheaper to buy 4 extra AA NiMH batteries to keep charged rather than upgrade to the faster chargers. So just keep some spares topped off and you should be fine.
Speaking of which, I have yet to see a consumer battery charger that isn't incredibly cheap feeling. Even ones for charging different chemistries or that let you set current rates are a mess of low-quality molding and cryptic button presses.
I've never had a problem with the basic 4-cell chargers that Panasonic includes with their Eneloop starter kits, other than the mildly annoying fact that they cover more than a single plug on a power strip.
Build quality seems fine, and I've been using them for decades without a single failure, so I've never seen any reason to even investigate alternatives.
100%, I am a huge fan of actual detachable batteries and I also store most electronics with them removed. I generally consider any rechargeable battery a risky thing to store. (Some explode.)
One thing I really love is power tool systems though: I have some Ryobi tools that are over 20 years old and they work with batteries sold in stores today. (The battery tech has changed but as long as your charger is for your battery tech, the tools are all good.) I rarely use a given tool enough to justify replacing batteries in it every 2-4 years, but I use one of my Ryobi tools or the other frequently enough to justify keeping a couple good batteries available at any given time.
I have a modern drill and impact driver because I use them a lot. But the handful of couple decade old saws are plenty adequate for the very rare occasions I need a jigsaw, circular saw, or sawzall.
If it makes you feel any better I’ve had to buy back cables that I have thrown away because I hadn’t used them for 15 years - and then found a project where I need DB9, SCSI, FireWire 800, Component to VGA converter or some relic.
Another reason they call me the cable guy at home ( though mainly because I probably have at least 800 cables in my studio )
If it makes you feel better, I just bought a used zoom h4 for cheap - it still works, but it uses mini-usb and I long ago toss those cables because I didn't have anything that used them. (I have a full audio workstation with a 18i20 interface in my office, but sometimes I want something portable)
Which is to say those might become useful someday again... Are they worth storing is a different question - since I'm looking for the cables anyway - both of the cables you mentioned can be bought for $5-$10, and the mini-usb I need is as cheap as $3. It will cost more more in shipping than the cable. (though I will likely look for something else I need to get free shipping)
I also have a hard time letting go of expensive cables merely because they were expensive. For this reason, I probably have as many parallel SCSI cables as I do USB cables, despite not having used a parallel SCSI device in years, including several 15+ meter HD68 cables that only work with high-voltage differential SCSI, despite owning exactly one HVD device.
OTOH, it's a large, loud, heavy, and ugly IBM 3590 tape drive that I'd rather not need to have at arms length to use.
Eneloops are fantastic. I've been using them for 10 years.
They have very low self discharge so you can keep them on the shelf for a year and they will still have 70% charge which is very different to most rechargeable batteries.
They don't leak unlike alkaline batteries and you can run them to 0% charge without damaging them unlike Lion batteries.
The terminal voltage is only 1.2v so there is the occasional thing they don't work well in.
That said my collection of eneloops get much less use than they used to as everything comes with built in lithium batteries and a usb charger nowadays. That is very convenient until the moment the lithium battery dies...
Changing the lithium battery in things sucks. Firstly it's really difficult to get a good one and not a crappy knock off. Secondly modern stuff isn't meant to be repaired. Every time I pick up my kindle I shed a small tear when I see the screen damage I caused changing the battery.
So, I buy stuff with AA or AAA batteries if possible and if I want it to last for more than 3 years.
I have a mix of eneloops and Amazon Basics, they seem pretty equivalent
> Every time I pick up my kindle I shed a small tear when I see the screen damage I caused changing the battery.
Don't shed a tear! https://en.wikipedia.org/wiki/Kintsugi
Repairs are beautiful.
Designers have a choice in lithium-ion though. 18650 is is pretty large cell but there's 14500 which is AA sized or 10440 which is AAA sized. They make versions with the usual battery "nub" rather than the flat faces for spot welding, and built-in protection circuitry to prevent over-discharging. You probably would want to use ones of a different size than normal 1.5v cells though. A personal favorite of mine is RCR123A/16340.
Even many of the pouch cells come in "standard"-ish sizes. An 803860 is nominally 8.0mm x 38mm x 60mm, but I am seeing more custom sizes recently.
Meanwhile, alkaline batteries can go to hell. You might as well plan on one leaking in the battery compartment. My favorite non-rechargable 1.5V AAs are Li-FeS2, which never leak and have spectacularly low self discharge (especially good for multi-year ultra-low-power projects), but are dammed expensive.
> Designers have a choice in lithium-ion though. 18650 is is pretty large cell but there's 14500 which is AA sized or 10440 which is AAA sized. They make versions with the usual battery "nub" rather than the flat faces for spot welding, and built-in protection circuitry to prevent over-discharging. You probably would want to use ones of a different size than normal 1.5v cells though. A personal favorite of mine is RCR123A/16340.
But other than 18650 you can't expect to find a lot of devices using any particular size.
We should strive for a couple blessed sizes that a lot of devices will stick with, where all cells include a nub and protection circuitry.
The form factor I'd like to see standardized would be a flat pack like the Nokia phone battery.
Not saying the cylinder doesn't have it's place, but so many of my devices would like a flat pack.
If that happened, it'd have the added benefit of being able to standardized a bms protocol for the packs. Hard to have control pins with a cylinder.
And if you were super clever, you'd make those packs stackable so they could be charged and discharged together.
I love the 14500 except for its footgun shape. 6 x 14500 is at least 21 volts, which won't play nice with a device that wanted 9 volts. I used to try to keep the 14500s far away from the AAs, but there's no stopping a kid in a hurry who wants to play with a toy or musical instrument.
I've taken the approach of electrical-taping my USB-chargeable 14500s each to a dummy-battery, since the things I put them in have 2 adjacent slots for series AAs. The voltage is still high (3.somethingV instead of 3V) but they seem to work.
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>Meanwhile, alkaline batteries can go to hell. You might as well plan on one leaking in the battery compartment.
On the other hand, alkaline batteries never burn your house down.
I also feel like they serve different purposes. Needed for long-term storage and only used in an emergency? (eg, a flashlight for power outages) You're probably better off going with old-fashioned alkaline batteries. Duracell claims they're good for 10 years. Needed for day-to-day usage? Lithium might be better: you can monitor for swelling, the battery recharge-ability is probably more important than any of the downsides that come with lithium ion batteries.
No, there's basically no reason you'd ever want an alkaline battery except cost. For your use case of long-term storage or a rarely used flashlight (e.g. in a car emergency kit), you'd want a Li/FeS2 as the parent poster recommended, also called just a "Lithium" primary (i.e. non-rechargable) cell. They have a longer shelf life, don't leak, hold more energy, can provide a higher discharge current, work over a wider temperature range, and have safety characteristics very similar to alkaline.
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> You're probably better off going with old-fashioned alkaline batteries.
Never. They will leak and die. Alkaline cells always end up leaking and dying in my experience, given enough time.
In fact, I do the reverse: If it's something I think will sit for a long time, I make sure to put a rechargeable battery in it. That way, worst case, it's dead—but it won't be destroyed by a leak.
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Alkaline has a tendency to leak electrolyte when stored in devices long-term, especially if used intermittently, even more so if the loads are at the upper end of what alkaline can handle as they are in many modern flashlights. The electrolyte is corrosive and often results in a broken device, which is exactly what you don't want in an emergency.
Li-ion's self-discharge is pretty low for a bare unprotected cell, and a flashlight with a mechanical switch consumes no power when off. One must take care to avoid short circuits when handling such a cell, but modern Li-ion flashlights have over-discharge protection, so that's the main safety concern with a single-cell design.
> My favorite non-rechargable AAs are Li-FeS2
Lithium Iron Disulfide. For those looking for a brand name, that's what these are:
https://energizer.com/batteries/energizer-ultimate-lithium-b...
I just worry that the voltage of these is a bit too high, if the device takes 3 or 4 in series. They tend to be around 1.8 volts per cell, significantly higher than a fresh alkaline AA at around 1.6 volts, and even after half the energy is discharged, if the device is off for a long while, the initial voltage for next turn-on creeps all the way back up.
(The price doesn't bother me ... it's worth the much lower chance of leaking than alkaline, if you leave it in a remote or gadget for years. But I've come to think that rechargeable NiMH like eneloops are a better idea due to the voltage.)
I’m visiting some family and I’m a hero for fixing a couple devices that stopped working from alkaline batteries by using a bit of foil paper to overcome the corroded contacts.
Maybe not great in the long run (steel and aluminum don’t like eachother)… maybe I should have put on some grease…
I swab the corroded contacts with white vinegar from the kitchen. It turns the white gunk into a foamy blob, and I assume it etches off enough of the corrosion to restore conductivity. I wipe the foamy part with the dry side of the cotton swab, and the device usually works again.
I started doing this as a kid, reasoning that the white gunk looked like baking soda, which is fun to combine with vinegar, so let's see what happens. I just looked it up, and it appears that the process is legitimate and safe. The vinegar turns potassium carbonate into potassium acetate, also producing carbon dioxide.
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The Xbox 360 was the most gamer friendly console (play your open music during games?!?) but one feature i loved was the battery packs. Your controller died? Just swap a pack - two seconds. And the packs could be rechargeable or AA so you could have a bunch of rechargeable AA for a fair price and never get bogged down waiting for anything to charge.
Series X controllers still work this way. Takes standard-ass AA batteries, including rechargeables; or you can buy a bespoke charge pack[1] which actually supports charging while in the controller.
[1] https://www.xbox.com/en-US/accessories/batteries-chargers/pl...
And, if you use good quality 2500mAh rechargeable AAs, those controllers go forever between charges.
I really wish more devices went this way. In devices these days the thing that will fail first, long before other components, is usually the battery. It seems disingenuous of manufacturers to claim that rechargeable batteries are good for the environment and then ship devices without user replaceable battery packs.
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Ditto for the Nintendo Wii Remotes and the Balance Board --- I still have a set of rechargeables from that setup.
I suck at electronics, so -
Could you possibly make a modern cell phone that runs off of rechargeable AA batteries?
How many would it take to have roughly the same amount of screen time?
ChatGPT says it's a bad idea, but roughly I'd need 10 AA batteries and a boost converter.
The best thing about Eneloops do not seem to leak. I can just leave them in rarely used electronic devices without worrying. They might discharge, but so far this has never been a problem.
Mentioned this above - so happy we went with Eneloops. Our battery waste is nearly 0, and no leaking..
I don't think that I've ever seen any NiMH leak. If you look at teardowns - it's maybe not even possible. They look rather dry inside.
Am I courting disaster by reviving won't-charge pouch cells by just manually running a bit of current through them until they're nonzero volts and then a normal charger will do the rest? So far, in the maybe half dozen times I've tried it (rectangular battery blocks for old digital cameras, the pouch cell inside a long-disused Kobo Reader) it's worked. They charge right up, they don't swell, and they still have decent capacity.
I'm running at the hairy edge and only high quality safety engineering is protecting me here? Or these cells can take a lot more abuse than they're given credit for?
I've thought before that it'd be nice to have some kind of device that would do this in a safe(r) fashion wherein you'd connect the 2 charging leads to the dead battery plus a temp sensor pad and it'd slowly bring the charge up to the minimum required for charging by a regular charger.
Over-discharged Li-ion cells can grow metallic lithium dendrites that result in internal short circuits. Charging them again following over-discharge does create a risk of fire/explosion.
I've jump-started my share of batteries this way. Such a deep discharge might affect lifespan but it's typically old devices we do this to anyway.
Cool. I have a modern (not smart) body weight scale and it regularly ruins this way at least one of the 3 GP NiMh rechargable AAA batteries I put in it, so I wanted to hear some ideas what could be done with them given they have been through only bunch of charge cycles.
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My offshoot rant is that it should be easier hold devices at a longevity charge.
I want some gadget that keeps my essential gear in a long-term maintenance mode. Oscillate it 20-80% or keep it at 50%, whatever is optimal.
Every time I've looked into building something like this it seems like there's no standard reporting of charge level over the wire. I would waste a genie wish on this to have it in the USB spec and widely adopted.
> it seems like there's no standard reporting of charge level over the wire
Isn't that the "Battery_Status" message in the USB PD spec? Page 152 in this pdf: https://e2e.ti.com/cfs-file/__key/communityserver-discussion...
Combine that with the "Battery_Capabilities" message (page 163) to get the total capacity, and you can calculate the charge percentage.
My Xbox 360 controllers are still in use. Meanwhile, I've resigned myself to never using any PlayStation controllers for more than three or four years.
AA and AAA batteries are great. I wish using them weren't considered a negative by many hardware reviewers.
You can get replacement parts for PS controllers, although they can be rather fidgety to open up.
Yeah, I tried fixing the wand controllers for PSVR, ordered batteries from AliExpress. It took an hour to get everything done, and I was constantly scared I'd break something. That was a few years ago. Now they are back to not working; I'm not sure if I can even still get the batteries.
> run at a nominal 1.2V instead of the 1.5V of alkaline batteries.
I've suddenly figured out why so many toys don't work with rechargeable batteries
That's not the reason.
Alkaline batteries only have 1.5V for a short time. In practice, toys are designed to opeerate off of 1V to 1.5V, because Alkalines vary _wildly_ in voltage during use.
NiMH at 1.2V _STAYS_ at 1.2V, even when drawing 1Amp or more (under these conditions, Alkaline would have long dropped below 1V).
EDIT: This is also a problem because "nicer toys" will measure the voltage assuming an Alkaline is "full" at 1.5V and dies at 1.0V. However, NiMH starts at 1.35V, then "plateau" at 1.2V, and stays there for most of its life, before rapidly falling off to 1.0V or .8V like a cliff at the end of its life. So NiMH life "cannot be predicted" by any simple metric.
I had an issue with the original Apple Magic Mouse that would not work correctly with NiMH batteries but work fine with disposable AA. The mouse would be fine for a few days then randomly stop working; using fresh NiMH would revive it again. I assumed it was due to 1.2v vs 1.5v but perhaps that particular mouse (or all Magic Mice) was just bad.
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You can now find 1.5V Li-on AA batteries with, and that's a game changer, built-in charger and a type-C port!
I have one in my wireless mouse. If it dies, I change it to a spare and charge it right from my laptop (and the battery that was empty becomes the spare)
I haven't used them, but IIRC they maintain a constant voltage until they're discharged, when it instantly drops to 0. That may be a problem, because if your device has any battery indicator, it will show the battery as full until the end. Nothing will tell you that you need to replace the battery before the device powers off. That's why I decided not to buy them. My mouse knows when my alkaline AA battery is low and gives me a warning.
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Came here to post this. I'm 100% agreed with Mr. Geerling.
For a fun challenge try to find a non-built-in-battery arc lighter (eg: candles, grills, etc). When I found one I bought four (think camping/disaster bag... if everything is AA/AAA then having a shelf-stable fire starter is easier/safer than lighter fluid).
For a fun sidebar check out the "Panasonic BQ-CC87AKBBA" which is effectively a combo "in/out" battery charger OR USB battery pack(!). It'll suck in (unfortunately) Micro-USB and charge your AA's, then switch a button and it'll spit that power back out as a battery bank. When I find one like that for USB-C, it's going on my christmas list.
Look up plastic battery holders that hold 8-10 along with a 4x charger and I just swap batteries out and recharge them into that buffer/holding cell. I'll have to look into the Eneloops as I've been working with the Amazon Basics and generally have 1-2 batteries fail out every few months (and am specifically looking for heat-resistant / outdoor applications).
Last one: Lots of cheap solar products have cheap rechargeable AA batteries inside... you can generally open them up and swap the battery out if they're not working any more (and/or potentially scavenge the charging panel if you think about it!).
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I believe I have zero Alkaline batteries left in my house and I'm relatively surprised that pretty much everything works fine. If anything, I suspect the only problem is that some devices have an inaccurate account of how dead the batteries are. But I use Eneloops on everything, even things surely not designed at all to run on them. (And I reckon you could probably make more devices work if you really wanted to; adding an additional cell or two in series would surely give you a voltage that's in range, if you can figure out a good way to do it.)
Of course not all rechargable batteries are the same; there are a few different rechargable battery chemistries in the AA form factor. I like Eneloop Pros, though; they've been very reliable for me. I've been using them for years and I've never had to throw one out yet; supposedly they last over a thousand cycles with most of their capacity.
I think I have only one device that uses AA - my central heating's radio thermostat. This thing has caused me untold hassle, which is only partially down to the batteries, but still...
Totally OT, but does anyone have a good link on how the thermostat gets paired with the boiler? I'm thinking of getting replaced and would like to talk to the gas fitter from a vaguely informed point of view.
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Three things prevent me from eliminating all alkalines:
* smoke and CO detectors with low-battery voltage sensors calibrated to alkaline
* some older electronics (e.g. multimeters) using 9V batteries
* my non-contact voltage tester refuses to turn on using NiMH, for safety reasons presumably
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If they don't work at 1.2V they weren't very good quality to begin with. AAs are dead at 1.0 or 0.9V.
There are a lot of low–quality toys.
A weird flipside is things like... the IKEA Zigbee devices. Many of these do not work right at all with 1.5V batteries and basically require rechargables.
I invested a few hundred dollars into Eneloops, but they kept disappearing. Turns out my kids were throwing them away, thinking they were disposable (cry).
I’ve since trained them and rebuilt my stockpile but that was painful, at what was then $2 a cell. (Now $3-4.)
Training for kids here is that batteries never go in the trash, since they all go to the same recycling place.
IKEAs rechargable batteries are great.
According to what I've heard, IKEA rechargeables are rebranded eneloops.
I have a bright label on each saying “Do not dispose”. Hopefully it’s enough to at least get someone’s attention to read or ask further before throwing them out.
I miss the old Rayovac batteries. They had a 10 year no leak guaranty, and it was real. I did get some to leak - I found a box of gear that I know hadn't been opened in 13 years, and even then it was a small leak that wouldn't be hard to clean up.
But Energizer bought the company and changed the formula.
Were the old Rayovac batteries alkaline or zinc-carbon? Zinc-carbon batteries use a "dry cell" chemistry that will never leak, have a low self-discharge rate, and are very cheap to make and buy. You typically find them marketed as "heavy duty." The trade-off with those are that they have a lower energy capacity compared to alkaline.
I use NiMH in almost everything but for things like TV remotes and clocks that sip power AND you can't be arsed to change them all the time, they work great. I buy a pack of 4 at the dollar store.
Some government needs to force some standards. Power tools are the worst. Each company is trying to create a network effect and it's anticompetitive.
Fortunately you can get adapters to take 18/20 volt batteries to any other (18 and 20 volt rechargeable are the same cells, but they measure the voltage differently). Likewise most 12v systems have adapters.
There are two issues: some manufactures put more smarts in the battery than others. So never run the battery completely dead which some combinations allow. Never charge the battery with other than the OEM charger.
Don't buy the off-brand batteries (which sometimes are counterfeit that look like the real thing) since they sometimes are not safe.
Well anything up to 240W can fit into USB-PD.
I have some LiPo-based 1.5V AA and AAA batteries that have USB-C ports built in for charging. The AAA ones claim 1200 mWh (800 mAh) and the AA ones claim 3400 mWh or ~2250 mAh. (I say "claim" because I bought them off some random Amazon shop a few years ago and haven't bothered to actually check.)
I have a considerable backstock of Logitech Anywhere MX (no bloody 2, 3, or 4...) mice in my drawer entirely because they can be powered by 2x AA batteries for months at a time. I like these because when the batteries die, I just swap them out and keep doing work.
I have one of the newer models and when the battery runs out, I have to stop what I am doing and charge the mouse. Yes, you can get through the rest of the day with a quick 5-minute charge but if you're like me, you won't remember to plug in the mouse at the end of the day and will have to repeat the quick-charge multiple times until I finally remember to plug it in overnight (usually by writing a sticky-note). I assume Logitech's answer to this would be: buy a second mouse as a backup!
The only major downside is that these older mice don't do bluetooth and USB Type-A ports are getting more and more rare.
This has greatly informed my decision to always try to buy things that take AA batteries, or at least easily replaceable li-ion batteries (at worst).
I found a Minidisc player that had been in storage for over 10 years, probably closer to 15. Runs off a single AA battery; I'd left it with a Duracell and it was still running.
This seems like more of a rant about non-replaceable batteries (of any type.)
When I buy things like flashlights/headlamps and other battery knickknacks, I ensure it uses a 18650 or some other standard lithium formfactor.
> It would be faster to leave the batteries in my tools, but over 40 years of sacrificing devices to alkaline cell leakage, it's my habit not to. So far I've never had leakage problems with the eneloops, but old habits die hard.
I've gotten burned by that too, but I just try to remember to take out the batteries before I put something into storage.
BTW, I think the old-style "heavy duty" batteries and lithium AAs don't have a leakage problem. Though lithium AAs are now ridiculously expensive. I think they went from $1 a cell to $2 in cell in a Sam's Club 18-cell bulk back over a couple of years.
A 4-pack of Eneloops was my first ever online purchase in life. I bought them off eBay, scared shitless I'd get scammed or my data stolen (I was very young; the online shopping industry, too). But they happily arrived in my mailboz one day.
They were for a Konica Minolta camera and they lasted surprisingly long. I think I saved about 30-40% of the price of the camera itself in recharging Eneloops, instead of buying new AA batteries every now and then.
Ahh the Sony Walkman. Yes, still useful. I bought one specifically for the AM radio, I use it in conjunction with a radio frequency generator (so old it uses vacuum tubes) to trace wires. Had to tape gauze over the headphones, the foam is long gone.
I'm always surprised that camping, and other outdoorsy, tools (i.e., flashlights, headlamps, satellite communicators, GPS, etc.) are increasingly powered by li-ion batteries. I think it's because there is currently an "ultralight" trend going on in the backpacking world, but it's still very annoying. When I go out, I just make sure everything, except for my Kindle, is powered by AA(A)'s. This way all I need is a dry bag with some extra non-rechargeable batteries, my battery charger, and solar panel.
This makes no sense. With the li-on batteries you would need everything you listed, minus the extra batteries.
At https://infinite-battery.com we're making a repairable battery where you can change the cells, because there's no reason your e-bike battery should work differently than your remote control: when batteries are drained, you can change them!
Can’t exactly relate to the post. I never had a device die on me like that. All my devices with Li-ion batteries are “daily drivers”.
I do tend to keep charge between 20-80% where possible, and fortunately haven’t seen significant battery degradation.
I’m on a 4 year old iPhone and even that easily gets me through the day still on 80% charge.
My only AA device is my HHKB keyboard and I wish it had a USB-C rechargeable battery instead.
Alongside their AA-powered keyboard, Apple sold a little two-cell charger with two AA NiMH batteries, which is still what I use to charge my Eneloops.
Whats the energy/volume comparison between standard AA batteries and li-ion batteries?
Highly variable based on load and the specific batteries involved. Alkaline will almost always have more capacity for something that takes more than a day of continuous operation to drain the battery, and NiMH will almost always have more for something that takes less than four hours.
Here's a tool you can use to compare different batteries at different loads, graphing voltage vs Amp-hours. The individual battery tests have more detail and graphs of voltage vs Watt-hours, which is often a more useful measurement.
https://lygte-info.dk/review/batteries2012/CommonAAcomparato...
Speaking of which, I really hate those chargers that force you to use two batteries instead of one. I get that it is cheaper to design it that way, but come on.
NiMH chemistry allows for safe overcharging though. If the chemistry allows for it, why not take advantage of it and have cheaper chargers?
The downside is that "save overcharging" only works at very low charging rates. That's why the double-charger designs all have 10+ hour charge times (mine actually has a 20-hour charge time).
But in practice? Its cheaper to buy 4 extra AA NiMH batteries to keep charged rather than upgrade to the faster chargers. So just keep some spares topped off and you should be fine.
Sure, but those NiMH have the same form factor by necessity, so it is confusing.
I would be surprised if the extra costs for the electronics for charging an extra cell are more than a few dollars.
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Speaking of which, I have yet to see a consumer battery charger that isn't incredibly cheap feeling. Even ones for charging different chemistries or that let you set current rates are a mess of low-quality molding and cryptic button presses.
Build one. Great, ambitious but doable newbie electronics project :)
I've never had a problem with the basic 4-cell chargers that Panasonic includes with their Eneloop starter kits, other than the mildly annoying fact that they cover more than a single plug on a power strip.
Build quality seems fine, and I've been using them for decades without a single failure, so I've never seen any reason to even investigate alternatives.
This is expensive but so far pretty nice. It's about the size of a console, though.
https://www.amazon.com/OLIGHT-Exclusively-Rechargeable-Batte...
100%, I am a huge fan of actual detachable batteries and I also store most electronics with them removed. I generally consider any rechargeable battery a risky thing to store. (Some explode.)
One thing I really love is power tool systems though: I have some Ryobi tools that are over 20 years old and they work with batteries sold in stores today. (The battery tech has changed but as long as your charger is for your battery tech, the tools are all good.) I rarely use a given tool enough to justify replacing batteries in it every 2-4 years, but I use one of my Ryobi tools or the other frequently enough to justify keeping a couple good batteries available at any given time.
I have a modern drill and impact driver because I use them a lot. But the handful of couple decade old saws are plenty adequate for the very rare occasions I need a jigsaw, circular saw, or sawzall.
I did something similar with my old 286 system. The CMOS battery failed and I rigged up a replacement using velcro and 4 AA batteries. Worked great.
Sadly I had to toss that system when I moved to a smaller apartment :(
Looking back, tossing it was a huge mistake.
> Looking back, tossing it was a huge mistake.
On the other hand, being afraid of ending up with similar feelings like you, I keep stuff.
So I sit here in a room where I'm probably one or two arms-length away from VGA and DVI cables and other relics, "just in case".
If it makes you feel any better I’ve had to buy back cables that I have thrown away because I hadn’t used them for 15 years - and then found a project where I need DB9, SCSI, FireWire 800, Component to VGA converter or some relic.
Another reason they call me the cable guy at home ( though mainly because I probably have at least 800 cables in my studio )
If it makes you feel better, I just bought a used zoom h4 for cheap - it still works, but it uses mini-usb and I long ago toss those cables because I didn't have anything that used them. (I have a full audio workstation with a 18i20 interface in my office, but sometimes I want something portable)
Which is to say those might become useful someday again... Are they worth storing is a different question - since I'm looking for the cables anyway - both of the cables you mentioned can be bought for $5-$10, and the mini-usb I need is as cheap as $3. It will cost more more in shipping than the cable. (though I will likely look for something else I need to get free shipping)
I also have a hard time letting go of expensive cables merely because they were expensive. For this reason, I probably have as many parallel SCSI cables as I do USB cables, despite not having used a parallel SCSI device in years, including several 15+ meter HD68 cables that only work with high-voltage differential SCSI, despite owning exactly one HVD device.
OTOH, it's a large, loud, heavy, and ugly IBM 3590 tape drive that I'd rather not need to have at arms length to use.
Ebay has various 286s for about $200, some even working!