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View Full Version : Battery holders in rechargeable battery packs?



Jonitus
02-07-2007, 12:35 PM
I'm somewhat ignorant in the ways of rechargeable batteries, so forgive me.

I need a 4.8V battery pack for my latest creation, and was wondering if a stacked 2+2 battery pack provides a good enough electrical connection between the cells and to the rest of the saber that I could just use it as the basis of the battery pack? What I mean is - could I get the proper battery holder, fill it with NiMH cells and shrink-wrap the sucker to make a battery pack that way...or should I just buy a pre-made battery pack with welded tabs and so forth?

It's going into a 1.25" tube, so the cells will have to be AAA in size for what I want to do with them and the associated electronics. Therefore, Tim's Sanyo 2500mAh pack will not work for me.

petriomelony
02-07-2007, 01:17 PM
Jonitus, i'm not sure whether you'd be able to recharge the pack as a single unit... if you put separate batteries in, my guess would be that you need to take em out and recharge em in their respective type of battery recharger. Though don't quote me on that.

Firebird21
02-07-2007, 01:22 PM
The shrink wrap idea should work as far as I know.

The biggest thing would be what you're using to charge them. A Uneversal Smart Charger is what you want. You'll be able to charge just about any battery set up with one of them, except Lithium Ions I think.


Check out this Topic (http://thecustomsabershop.com/forum/viewtopic.php?t=1732) for some more info.

xwingband
02-07-2007, 03:33 PM
Yeah, there's no problem if you use a normal battery pack. I've done that before. In fact the shrink wrap isn't really needed. That way if you find higher capacity ones later you can swap them.

The real benefit of the premade ones like Tim has is they're slightly smaller because it's just the shrink wrap and the batteries.

Depends on what you want to do. I've bought same... made some... put them in battery holders. So big deal.

Firebird21
02-07-2007, 07:36 PM
If you're going to use the battery holder without the shrink wrap make sure you at least tape it up with some electrical tape.

I've had my batteries get dislodged while dueling. A little tape, problem solved.

neophyl
02-09-2007, 08:15 AM
The other thing to watch our for with the battery pack holders and charging is heat. Ive been using both pro and home made battery packs in lasertag weapons for about the past 11 years now and Ive seen some nasty results of improper pack useage.

If you quick charge your batteries which alot of the smart chargers do, then they can pump in several amps. This heats up the metal contacts of the battery pack, which as they are under spring tension melt their way through the plastic of the battery holder.

This causes the contacts to either a) lose alot of the tension with the cells making loss of power when the pack is jolted more likely or b) complete destruction of the holder leading to a possible catastrophic meltdown as the batteries all short out due to touching your nice metal hilt.

I would rcommend the extra heatshrink to stop that possibility. If you only trickle charge your packs then of course this isnt a problem.

Firebird21
02-09-2007, 10:25 AM
My charger has 3 settings, 1,2 and 4 amp charging. I just now charged my 4-AAA square pack at 2amps and it was rather warm, I could still hold it, but if I had charged it at 4amps, I doubt I'd be able to.

Moral of the story?

If you can get a Smart Charger with the diffirent settings like mine, I'd go for it! It's worth the coulpe extra bucks to save your batteries and your saber.


This is the one I have. I think it was about $35 at my local hobby shop.

http://www.yankeetoys.org/lee/Luke3.jpg

It will also trickle charge once it's over about 90% charged and it will "condition" the batteries too. Whatever that means... Ask James, he said it's really good. Makes them last longer or something.