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• It should go without saying, but just be careful with the individual cells once you take it apart, if they're not individually shrink wrapped; it wouldn't be a bad idea to shrink wrap or wrap electrical tape around them if you're going to keep them as loose cells for a while. If one battery rolls against another and shorts its end terminal to its own case, it'll quickly discharge, often exploding. I learned this the hard way a long time ago, tossing a bunch of these in a plastic container for storage and ended up with a bunch of firecrackers.

  Posted by: evandude on January 2, 2007 at 8:24 AM

• IIRC these dinky little cells in the 9V case are identical to the 'AAAA' batteries that I tried and failed to find for a graphics tablet years ago.

  Hmmm... yep, Wikipedia confirms it:
  http://en.wikipedia.org/wiki/AAAA_batteries

  Posted by: IrregularShed on January 2, 2007 at 8:37 AM

• I have taken apart 9 volt batterys and they were just one unit. It's been some time I think I did that (last time) in the 1980's. Come to think of it I may have a photo of one cut in half if I do I will try to post it on fliker
  Also if you take apart the 6 volt lantern batterys they look like 4 long D cells.

  Posted by: Prussian7 on January 2, 2007 at 9:30 AM

• Yes, many 9V cells are like that, however many use a cell the size of the battery.

  Posted by: wonderground on January 2, 2007 at 10:14 AM

• This is a good intro to a handy little niblit. If you purchase 9 volt recharageable battery (actually 7.2 Volt) you can make small rechargeable packs by cutting off cells as necessary. Make sure and leave enough of the solder tabs for your own wires. Sometimes the rechargeables have the 6xAAAA configuration, sometimes they are six little stubby cells about half an inch long. Either way they make a very compact battery pack. This information applies to Nicads, but I would guess the newer NiMH rechargeables are of similar construction.

  Posted by: howajo on January 2, 2007 at 10:42 AM

• And don't throw those parts out either! You can make your own 9 Volt battery snaps out of them, much much better than the ones you get at the stores (the cheap ones at least).

  home made 9V battery snaps

  Posted by: remmelt on January 2, 2007 at 11:09 AM

• the old russian (actually soviet's) 9 volts batteries, named "Crona" ("Крона"), had a few plastic rectangular prisms stacked vertically. The inside structure were like coin cell batteries.

  Posted by: J0ker on January 2, 2007 at 11:17 AM

• As a matter of fact, I did nearly hurt myself taking a 9v battery apart when I first heard about this several years ago. As I was trying to remove the cells, several exploded. It was quite loud and forceful... So, please use caution..

  Posted by: sboger@hotmail.com on January 2, 2007 at 11:18 AM

• Not all of them are like this.
  I took apart an older (2002-2003 or something) rayovac, and even though is clearly had 6 cells, there were completely connected and the shape of the battery itself.
  

  Posted by: mastershake916 on January 2, 2007 at 12:49 PM

• Time for a terminology lesson.

  A single unit of electrochemical power generation using an anion, a cation, and an exchange solution is called a "cell."

  A multiple unit of such tied together in some way is called a "battery."

  That's why it's a 1.5V cell, but a 9V battery. Because a 1.5V "battery" is just a single cell.

  Technically a "potato battery" is a half-cell (not a cell or a battery). I forget what the precise distinction is between a cell and a half-cell though.

  Posted by: _fluffy on January 2, 2007 at 4:56 PM

• 
  a cell is comprised of two half cells.

  in one half cell a chemical gives up electrons.

  in the other half cell a chemical takes up electrons.

  the half cells need to be connected to
  exchange the negative and positive ions
  resulting in a cell.

  Posted by: johnpost on January 3, 2007 at 1:11 PM

• [these dinky little cells in the 9V case are identical to the 'AAAA' batteries that I tried and failed to find for a graphics tablet years ago] Actually these are reverse polarity from standard. I took one apart several years ago after learning about the trick from the "LED Museum".

  Posted by: WonderWheeler on January 4, 2007 at 12:54 PM

• I did the same. Tore apart a duracell 9v and used 1 cell in the touchscreen stylus of an averatec tablet computer.
  Took a while to figure out that there was actually a dead battery in the stylus. Thought it was too small for a standard battery. That's when i learned about the AAAA's :) I couldn't find one in the local stores but worked sweetly with a little bending of the attached "straps" between cells. As mentioned before watch the polarity, mine were also opposite to what you would think.

  Posted by: intercranial on January 14, 2007 at 5:31 PM

• After seeing this, I tried ripping out the existing 6 aaaa cells from an Energizer 9v and replacing them with 6 rechargeable aaaa cells of 300mAh each. The plan was to make a 9v rechargeable that, on specs alone, should last a very long time. Imagine a 1,800mAh rechargable 9v? It didn't work. All seemed well while it was sitting on the charger, but when is wasn't connected to anything, it would heat up as though there was a short circuit - which there wasn't. If there was, the led on the battery charger wouldn't have come on. any ideas where I went wrong?

  Posted by: Petebass on December 22, 2007 at 3:01 AM

• After seeing this, I tried ripping out the existing 6 aaaa cells from an Energizer 9v and replacing them with 6 rechargeable aaaa cells of 300mAh each. The plan was to make a 9v rechargeable that, on specs alone, should last a very long time. Imagine a 1,800mAh rechargeable 9v? It didn't work. All seemed well while it was sitting on the charger, but when is wasn't connected to anything, it would heat up as though there was a short circuit - which there wasn't. If there was, the led on the battery charger wouldn't have come on. any ideas where I went wrong?

  Posted by: Petebass on December 22, 2007 at 3:01 AM

• "The plan was to make a 9v rechargeable that, on specs alone, should last a very long time. Imagine a 1,800mAh rechargable 9v? It didn't work."

  Nope, it won't. It'll be a 300mAh rechargeable 9v, or a 600 mAh 4.5v, or a 900 mAh 3v, or an 1800 maH 1.5v battery. Parallel-versus-series.

  Posted by: Norm on January 4, 2008 at 10:31 AM

• Would be very interested in getting hold of some re-chargeable AAAA - Thanks

  Posted by: PhilC on January 14, 2008 at 4:03 AM

• Ah, that's what was periodically going off with a loud bang in my home office. And I guess that's why. First time was about a week ago. All of a sudden, blam, like a gunshot right next to me. A nice cardiac moment, but I couldn't figure out what it was. Then it happened again a few minutes ago and I managed to localize the sound a little better. Found an old Duracell 9-volt the cat had apparently knocked down into the gap between my desk and the filing cabinet. The bottom plate was completely blown off and the ends of the cells were a twisted wreck. Kind of freaked me out. No idea what it shorted against, but damn.

  Posted by: JohnS on February 2, 2008 at 12:50 AM

• hey thank's for this i have a jabra bt2040 and i need battery's for it so i read this and did it and know my bluetooth headset work's thank's guy's i could not find the 4 AAAA battery's anywere but Radioshack it costed 5 buck's for 2 battery's what a rip thank's guys for this it work's great but one thing thouth i put the battery wrong and then it started to get hot so i left it out for a while put it the other way and it worked .

  Just be very cautios

  i didnt use no thin plier or any thing just a normal plier and a Knife and a scior worked great and rember to bend the tab's

  Posted by: b18 on February 25, 2008 at 1:53 PM

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