Ode to the AA Battery • Hacker News Board

Re: Ode to the AA Battery

#61

Post by everdrive » Fri, Jan 30, 2026, 5:12 PM UTC

aftbit wrote: post #32

everdrive wrote: post #26

Earlier quoted context omitted.

>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…

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 t…

That's an interesting counterpoint, thanks for letting me know. I was really under the impression that lithium ion batters discharged more aggressively. Maybe that's just more reflective of how they lose capacity over time? Can you speak to the fire risk?

Re: Ode to the AA Battery

#62

Post by jasomill » Fri, Jan 30, 2026, 5:15 PM UTC

embedding-shape wrote: post #20

jmclnx wrote: post #18

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".

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.

Re: Ode to the AA Battery

#63

Post by amelius » Fri, Jan 30, 2026, 5:21 PM UTC

dragontamer wrote: post #12

amelius wrote: post #4

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 tha…

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.

Re: Ode to the AA Battery

#64

Post by dragontamer » Fri, Jan 30, 2026, 5:30 PM UTC

amelius wrote: post #63

dragontamer wrote: post #12

Earlier quoted context omitted.

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 tha…

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.

NiMH cells are like $1 each. Seriously, Amazon.com is quoting me $18 for 16 cells, AA Amazon Basics NiMH.

As I said earlier: it's likely a better strategy to buy 4 extra cells and keep them pre charged / topped off, rather than spending a few dollars on a better charger.

Re: Ode to the AA Battery

#65

Post by orev » Fri, Jan 30, 2026, 5:41 PM UTC

cbdevidal wrote: post #24

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.

Re: Ode to the AA Battery

#66

Post by rini17 » Fri, Jan 30, 2026, 5:48 PM UTC

bxparks wrote: post #56

jchw wrote: post #7

Earlier quoted context omitted.

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; addi…

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

There are 9V NiMHs, too. They just need dedicated charger.

Re: Ode to the AA Battery

#67

Post by dhll » Fri, Jan 30, 2026, 5:51 PM UTC

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.

Re: Ode to the AA Battery

#68

Post by eulgro » Fri, Jan 30, 2026, 5:54 PM UTC

dhll wrote: post #67

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…

This makes no sense. With the li-on batteries you would need everything you listed, minus the extra batteries.

Re: Ode to the AA Battery

#69

Post by incognito124 » Fri, Jan 30, 2026, 5:58 PM UTC

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.

Re: Ode to the AA Battery

#70

Post by m3047 » Fri, Jan 30, 2026, 6:00 PM UTC

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.