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Ode to the AA Battery

jeffgeerling.com

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Re: Ode to the AA Battery

#161

Post by dragontamer »

amelius wrote: post #156
dragontamer wrote: post #148

Earlier quoted context omitted.

That's not how it works at all. When one is 80% and the other is 100%, the full one enters a state of over charge, reaching 105% or even 110% charge. This is safe. The H2 reaction then rapidly speeds up, leaking energy in the form of heat. The full battery heats up from overcharge but is otherwise safe. You end up with both batteries at 100% and maybe 110%, and a day or two later the 110% overcharge settles down to 1…

Ok, but do you agree that in this day and age of cheap electronics, it is really not worth it to even consider all this and it is better to just make a charger that doesn't overcharge and doesn't come with extra instructions?

It doesn't really make sense to buy a $20 charger when you only have $16 or so worth of AA cells (ie: a 16 pack from Amazon Basics). The $10 charger makes a lot more sense.

As for the knowledge problem: that's easily solved. I already told you what to do so you know how to work the $10 charger now. If you still want the $20 charger that's fine, it's your money.

Re: Ode to the AA Battery

#162

Post by js2 »

ploxiln wrote: post #90
js2 wrote: post #34

Earlier quoted context omitted.

> 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 chanc…

I can't think of too many places I'd use Li-FeS2 other than maybe in smoke alarms. They're available in 9-volt form factor. I use NiMH or Li-ion pretty much everywhere else these days.

Re: Ode to the AA Battery

#163

Post by bluGill »

accounting2026 wrote: post #132
bluGill wrote: post #128

Earlier quoted context omitted.

Alkaline. Rayovac spent a lot of money making alkaline that wouldn't leak (after several years of research one guy's wife asked "why don't you encase them in steel" - turns out that works, or at least that is how I heard the story). They never has the capacity of the more expensive competitors, but for my camping stuff I'll take that trade off. (all too often the last trip of the year I'm throwing everything in a box…

At our high school we each had to buy a TI-83 calculator kit, and it came with one of those Rayovac alkaline chargers. I also had a Seitek Eco charger that could charge "normal" alkalines. But you had to be careful not to discharge them too deep. It seemed kind of pointless over rechargebles though the capacity of NiCD/NiMH was way lower back then (I remember when NiMH AA batteries at 700 mAh were considered really h…

I forgot about those, the rechargeable existed too, but their regular non-rechargable were the ones that didn't leak.

Re: Ode to the AA Battery

#164

Post by nosrepa »

jasomill wrote: post #60
alnwlsn wrote: post #30

Earlier quoted context omitted.

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.

6 inch extension cords are a blessing I didn't know I needed until I had them. Now every charger takes up exactly one outlet.

Re: Ode to the AA Battery

#165

Post by nosrepa »

conception wrote: post #5

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.

I believe some 8bitdo controllers have this as well.

Re: Ode to the AA Battery

#166

Post by abracadaniel »

cogman10 wrote: post #109
Dylan16807 wrote: post #80

Earlier quoted context omitted.

> 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 RC…

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…

A standard that works something like nvme drives would be neat. Room for a longer flat battery, cool use a full size. Don’t have one? That’s fine a short one will still work.

Re: Ode to the AA Battery

#167

Post by fanf2 »

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…

> there's basically no reason you'd ever want an alkaline battery except cost

Rechargeable batteries are much cheaper than disposable single-use batteries.

Re: Ode to the AA Battery

#168

Post by Pxtl »

Dylan16807 wrote: post #115
Pxtl wrote: post #100

Earlier quoted context omitted.

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.

Are those LiFePO4 batteries that cap around 3.6V, or normal lithium ion that cap around 4.2V? I'd be cautious with either kind but especially with the latter.

They say 3.7v, so probably the wrong kind.

Re: Ode to the AA Battery

#169

Post by eternityforest »

I'd love to see a new battery standard.

Something future proof for new chemistries, consumer friendly and self protected, able to be series-es and paralleled if needed, etc.

Maybe even designed to be an external part of the case like 2 way radio and tool batteries, with the option of a retaining screw for toys and tamper resistance.

A few different sizes, from keychain up to power tool, and paralleling adapters to go bigger.

The electronics would probably cost pennies in volume, just like the tech that goes into those lithium AAs with built-in chargers and buck converters that are almost really awesome.

Re: Ode to the AA Battery

#170

Post by geerlingguy »

vel0city wrote: post #145

Project Farm has had a number of good reviews on alkaline, lithium primary, and NiMH AA batteries. He's tested so many with some pretty through tests. Best AA Rechageable Battery? https://www.youtube.com/watch?v=-jXQNY6rve8

Indeed, that video was half of the inspiration for writing up this blog post (and is linked in the footnotes!). Always amazed by the depth of his tests for videos that are published on a weekly schedule.
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