For a long time, I was on a mission to eradicate all but AA batteries from my life. It was a quixotic mission, at best, as it seemed that every time a "must-have" bit of electronic kit came out, it would have some exotic battery (Coast Flashlights & "N" cells, various handy gizmos with "AAAA" cells).

In the last year, the amount of kit I have with various button cells - those flat disk batteries - seems to have proliferated. Add to that my kids getting various toys of all sorts, and I had to concede defeat and start stocking a level of button batteries in the same way I stocked AA cells (and, I have to admin, "D" cells, which are exceedingly wonderful for their power to weight ratios).

But what to stock? There's approximately 3,456,344,023 slight variations on the button cell theme, but after a review of what we have and use the most, the list quickly trims down to the following:

CR2032 - This flat battery is found in everything from your desktop computer (it backs up the BIOS settings) to wrist watches. It's used in remote controls for electronics and in some garage door opener transmitters.
Pricing for CR2032's are insane. If you buy at a local store, they can be as much as $7.00 each, or you can buy online at a place like atbatt.com for about $1.34 each, and if you buy bulk packs (be careful, a lot of scammy operators out there) you can get them for as little as $0.35 each. I keep about 20 of them on hand.

CR2016. It looks like a 2032, it isn't. Used in much lower-drain applications, like clocks and remotes, the 2016 is the same diameter and half the thickness of a 2032. I also keep about 20 on hand.

LR44 (also called A76) is a relatively common small button cell. I've found this one in toys and devices of all kinds. I keep 10 on hand.

LR41 This is one of the most confusing of cells but I find it in a LOT of small devices and lights, and it's the battery used in the new eGear PICO light.
The LR 41 spec is for a 7.9mm Diameter, 3.6mm high, 1.5v alkaline cell with a 25 MaH capacity. But there are other 7.9 mm cells that are ALMOST the same height - the SR 726 at 2.6mm height and the SR721 at 2.1mm in height and the SR731 at 3.1mm height. They all will fit an LR41 opening - in the diameter, but the the device may not quite close right, and the voltage is 1.55 volts, which is not really a big deal, but it's not spec for the LR41. (Get my battery spex from this chart PDF file http://www.maxellcanada.com/pdfs/batteries/watch_micro.pdf) I keep 20 to 30 of these things around because they tend to be used in clusters of 3 in the devices I use.

Buy online, it's a lot cheaper. These batteries keep a long time, so you don't need to worry too much about them. There's a lot of stuff (like GPS devices) that use button cells for memory and settings backup and you tend to not notice them until they fail - after years and years of use.

I have kept to my guns about what to stock for batteries for well over a decade now. I pick up economy packs of AAA, AA, C and D as well as 9v transistor batts. I try to avoid owning anything that takes something other than those standards. The ones I stock are fairly universal, and can be had in everything from cheap industrial style to Lithium Ion. If I had to use a device that wouldn't accomodate one of these size batteries, I would grab an external battery holder and kluge it onto the device so I could use one of the standards.

I wouldn't have anything to do with 9v except that the CO and smoke detectors have to have them, and kluging those devices could get me in a lot of trouble if something went wrong (tampering with such safety devices is a no-no). As yet, there hasn't been anything I couldn't do without or find a substitute for that wouldn't take one of the standards, excpet that G2 Nitrolon flashlight I bought on an impulse in Baghdad.

I've been careful to not buy any gear that doesn't take AA's, kids toys don't fall under my gear list so they may have others but even then they tend to be AA, or AAA, or C or D. The only things I have that take coin cells are vehicle remote keyless which the physical key is the backup so I just toss a pack of those coin cells in the glove box.

All out computers are laptops and those have a small internal nicad back for the settings so its not a replace every couple years like a desktop. I've found nothing else I need that takes coin cells.

I have lithium AA and AAA's as my normal use and spare batteries about 20 of each size and 8 D lithium's plus 4 9 volt batteriew in my spares. I don't use C's or 123's so have none

I also am trying to lessen the logistical nightmare of battery types. I am finding it hard to do with infant/toddler toys but luckily they will grow and add a new challenge when the toys change. As far as the rest of my gear, the easiest thing for me is to think about multitasking different lights, etc.... to eliminate the challenge of stocking different batteries.

I have had good luck and great service from batterybob.com for all types of batteries. I'm just a happy customer, not involved with them at all.

Love the site, longtime lurker and first time poster.

Sean

Welcome to the site sperry!

I do it a little differently. I tend to look for items that use the "C" size. I do this because it's the least commonly used standard size battery. I have at least one radio and a couple flashlights that use C's.

If something happens and the standards run short, I suspect the AA and D sizes will go fast with plenty of C's left over.

Hi Sperry;

I am not sure of which brands at the moment, but I found some of the 9 and 6 volt batteries were just smaller batteries bundled in the case.
I opened one dead 9 volt out of curiosity once and found it was full of LR44 size button cells. Not all of them are like that though.
I am sure there is a list somewhere detailing what is in which cases. It might be handy to know.

I use rechargeable batteries for all the standard sizes.
Newer rechargeables like nickel metal hydrides perform quite well

I have standardized on AA and AAA Eneloops (or a store branded generic eneloop) for all our battery needs. These are used for the flashlights, mp3 player/radio, one small portable radio in the BOB, and one camera.

Beyond the above, I am not much of a electronic gadget person and do not foresee purchasing any new battery required gear in the near or longtime future.

I try to stick with AA (lithium & alkaline) and CR123 as much as possible. I do keep a few 9V around for the same reasons that benjamin mentioned. I also keep a few spare CR2025 batteries around for car remotes & a few D cells around for the Mag lights that I can't seem to get rid off.

The key to maintaining my battery stash is keeping some in a readily accessible location and the rest in the safe where the wife and kids can't raid the "reserve".