Custom battery pack tips?

joevennix · Post by **joevennix** » Sat Oct 07, 2006 12:20 pm

A while ago I bought one of those 7.2V 2000mAh battery packs from Radioshack, it looks like this:

In my current project I don't have room for both columns of batteries, but I can fit one column on each side. What is the easiest way to "reformat" this battery pack into such a layout?

I have considered buying six "C" cell holders and lining them up, but I'm afraid they might take up too much space.

Kyosho · Post by **Kyosho** » Sat Oct 07, 2006 10:43 pm

Here's what I'd do, but I do things ghetto stylee.

Remove the plastic casing junk. Seperate the batteries, get some spring type things (the negative side of battery compartments, salvaged from other electronics), and tape 'em on good with wires attached. Or just tape the wires themselves to the batteries, though you wouldn't get a good, solid connection.

You could try solder...but it frightens me.

SCARY! RUN AWAY!

AHHH!

Post by **bicostp** » Sun Oct 08, 2006 7:24 am

Why use RS battery packs when Duracell makes 2650mAh NiMH rechargeable AAs?

<s>Well, anyways, just seperate the individual cells in that pack and re-connect them in the same layout they're in now, but make the wire between the two stacks of batteries long enough to reach.</s>

Wait, that's NiCd! UNCLEAN!! Stay back!

Seriously, go get some rechargeable AAs. They're based off a superior chemical compound, have a higher capacity, and are much smaller than that battery pack. (Looks like that thing's made of <s>4</s> 6* NiCd C cells)

You can use that if you really want to, but I think you'd be happier using better batteries that don't take 5 hours to charge.

Edit: *better? : P

vskid · Post by **vskid** » Sun Oct 08, 2006 9:15 am

bicostp wrote:(Looks like that thing's made of 4 NiCd C cells)

I think it has 6, because thats how many my 7.2v NiMH pack has. If you got a NiMH pack, I think the batteries end to end with each other are some how held together, so you could just break the connection with the two bottom ones and then put them where you want (they might not be held together though, so your risk).

joevennix · Post by **joevennix** » Sun Oct 08, 2006 10:53 am

Well thanks guys, I figured out last night that inside the pack, the two columns were probably held together on their own with heatshrink, and were spot welded together at the bottom. I cut off the packaging and, sure enough, both columns stayed together on their own. I cut the metal tab they were welded to and separated them. Worked like a charm.

The main reason I use Ni-Cads are their price, it was like $20 for 6 of them plus a charger at Radioshack. Very easy to get. I realize you can get Ni-Mh AA's for cheaper, but the only kind of chargers they seem to sell are those that you have to take the batteries out, stick them in the charging unit, and plug it in. I don't like that too much.

Do you know anywhere that sells a AA charger that plugs into the pack? That would probably be a better option.

Post by **gannon** » Sun Oct 08, 2006 11:08 am

That charger shown would work with a 7.2V pack of NiMH AA rechargables as well.

Post by **marshallh** » Sun Oct 08, 2006 11:15 am

The main reason NiMH AAs suck is because they can't handle a large current load. I used 2500mAh AAs in my first N64 portable, and I got around 25-30mins playtime, even though they were fully charged. They ended up getting extremely hot and burning the plastic in their holders.
Lesson being: use Sub C cells whenever you can. There's a pretty good reason why not everyone's using AAs yet.
For charging, sub C NiCds blow the doors off of AAs - even charging my AAs with a hobby-grade MRC Superbrain at 0.5A, they still heated up quite a bit, where as there's no problem charging sub C NiCds at 3.5-4.0 amps. I think the benefits outweigh the size.

Post by **bicostp** » Sun Oct 08, 2006 12:51 pm

Hmm... I wonder how long they'll last with a PSone then. (I think its draw is 800mA... could be wrong though.

Ben wrote:Initial tests showed this setup consumes an average of 840mA, which is about the same as a VCSp!

^ From the 2001 PSone Portable page, which shows the PSone hooked up to an LED modded Casio TV. The battery he used was a SOny NP-550 (roughly 1700mAh). Judging by the estimate on that page I should be able to get about 2 hours out of these batteries, though I might be mistaken.

Oh well, if these don't work out, I have a ton of other stuff that takes AAs.

Website · Post by **Life of Brian** » Sun Oct 08, 2006 9:45 pm

I just recently finished my portable SNES with an LED modded PSOne screen (I'm yet to post a "finished" page because I need to borrow a camera...) but it runs off of either wall power or six AA 2500 mAh NiMH batteries. However, I only seem to be getting just under two hours of play time (and that's with the sound almost all the way down). I suppose marshallh's right about how much of a load they can handle, because an LED modded screen should only be around 350 mA and SNES mini another 350 mA, right? So, 2500/700 = 3.6 hours or so (am I right in guessing that's 3.6 hours "max"?) However, I can hardly reach 2 hours. Whatever happens, I just know that from now on I'm going with Sony Infolithium L's, because I seem to find plenty for around $30 on eBay (and that's a "Buy It Now" price) that are around 6000 mAh.

Post by **CronoTriggerfan** » Sun Oct 08, 2006 10:08 pm

That's a shame. I used one of the 7.2 volt packs like this, only mine was a Ni-MH rated at 3200mAh, and I got just shy of 6 hours of playtime out of mine!

And Joevennix, I recommend you get this battery pack rated at 3300mAh, or if you've got the cash, this one rated at 4200mAh or this one rated at 4500mAh.

CTFan