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With AA batteries, are the silver terminals the only conductive parts on an AA battery? That is, is the outpost ring around each terminal (part of the body casing?) conductive? I'm asking because I'm thinking to use conductive fabrics as terminal contacts. Because they're soft, they could wrap around the terminal.

Thanks

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  • \$\begingroup\$ Obviously the terminals must be strong enough to sustain load from all reasonable usecases. \$\endgroup\$
    – sharptooth
    Jun 29 '15 at 11:19
  • \$\begingroup\$ @sharptooth what is a use case in which the fabric could falter? \$\endgroup\$
    – Kar
    Jun 29 '15 at 11:21
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    \$\begingroup\$ You're kidding, aren't you? Users can be very careless - they will try to fit a battery with a wrong terminal into the compartment and force it rather hard when it doesn't fit. If this causes a battery rupture and any damage to the user of equipment thereof that's a lawsuit in many jurisdictions. \$\endgroup\$
    – sharptooth
    Jun 29 '15 at 11:29
  • \$\begingroup\$ But if the battery ruptures because of a wrong terminal, it won't rupture any less if it was a metal contact though. \$\endgroup\$
    – Kar
    Jun 29 '15 at 11:32
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    \$\begingroup\$ I appreciate the possibility of rupture due to physical abuse. But I'm talking about conductive fabric, which is soft. That'd even reduce the chance of physical rupture from pushing too hard since the case is soft. \$\endgroup\$
    – Kar
    Jun 29 '15 at 11:42
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Nope.

The entire body is conductive and wrapped in a tiny layer of plastic.

And: Fun part: With standard alkalines (thanks Nick) it's the + that wraps all the way round. At the negative you can actually make a small screwdriver glow by jabbing it in the tiny opening between the negative and the body. (THIS IS DANGEROUS! DON'T DO IT! ETC! But you could... :-D )

EDIT: Since you appended your question:

You could look into using conductive fabrics, but these are built up of normal fabric with conductive fibers inside, often metal. These fibers can creep into the gap between poles. You need to make sure of two things:

  1. Loose fibers can't be allowed to creep inside the gap! (short circuit = heavy damage!)
  2. The sheath around the battery might be damaged before it is inserted, so you need to protect from that, or creeping won't be the problem, it will be full-out contact through your wrapped fabric.

For the creeping problem you may be able to find plastic rings they use in building NiMH or NiCd battery packs to protect terminals from the wires running across. If you are going to be Alkaline, Zinc-Carbon (again, thanks Nick), NiMH, NiCd and Whatever chemistry compatible you need to protect on both ends.

To protect against sheath damage you need some non-conductive fabric or material otherwise in between, that actually wraps around, or this will be a problem at one time and you are not going to enjoy that.

End of EDIT

This is also something Dave Jones highlighted when he was tearing down these "battery booster clips". Next to the facts that many of the claims are exaggerated and/or bullshit, the entire metal clip is connected to the negative, which could cut into the plastic and short out your battery, which is a safety hazard.

That is beside the point of your question, but it's a fun little distraction when thinking about AA batteries, to have Dave explain all their properties to you:

Dave Jones about AA battery booster clip, if you're interested.

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  • \$\begingroup\$ Right. I'm actually thinking of using conductive fabrics as terminal contacts. Because they're soft, they could wrap around the terminal if pushed hard enough. Does it mean it's not a good idea to use fabrics as terminal contacts? \$\endgroup\$
    – Kar
    Jun 29 '15 at 11:13
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    \$\begingroup\$ Which terminal forms the 'body' depends on the battery chemistry. \$\endgroup\$ Jun 29 '15 at 11:21
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    \$\begingroup\$ To clarify: Zinc-carbon and Zinc-chloride batteries have negative bodies. Alkaline batteries have positive bodies. \$\endgroup\$ Jun 29 '15 at 11:35
  • \$\begingroup\$ @NickJohnson Good point, I'll add "With Alkaline" to it. Thanks. \$\endgroup\$
    – Asmyldof
    Jun 29 '15 at 11:54
  • \$\begingroup\$ @Kar That depends. If you can make sure the fabric doesn't creep into the gap and doesn't damage the sheath it might be doable. You could see if there's special plastic rings like the ones used in NiCd and NiMH battery packs that you can get, which at least protect the small gap between body and complimantary pole. \$\endgroup\$
    – Asmyldof
    Jun 29 '15 at 11:56
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A multi-meter would provide the quickest and surest answer.

I've seen different batteries have the case being either connected to the positive terminal, negative terminal, but usually (in the last 20 years) not connected to either.

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