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RevengeoftheSeth
10-24-2010, 04:50 PM
So I just finished the chasis system for my daughter's saber for her birthday, and I had centered it around a 18500 cell (I had 4 of them handy at the time), but they aren't exactly a common size.

It works for now, but my question is - if I decide to change the battery solution to a more common size, what should I use that will fit inside a 1" diameter PVC pipe and is not longer than 50mm? I didn't allow for any extra length in the battery (due to cram-fu restrictions).

Here is a picture of the chasis for her saber. Nothing fancy.

http://i14.photobucket.com/albums/a321/dontstopthabeat/th_DSCN0619.jpg (http://s14.photobucket.com/albums/a321/dontstopthabeat/?action=view&current=DSCN0619.jpg)
jjshumpert
10-24-2010, 05:37 PM
with a little chasis rework 4 1000mah AAA's will fit in place of your 18650 no problem
hrdwarhax
10-24-2010, 06:15 PM
isnt it 14500 that aaa and 18650 thats slightly bigger?
jjshumpert
10-24-2010, 06:22 PM
18650 is roughly twice the size of AA
RevengeoftheSeth
10-24-2010, 06:42 PM
18650 is the standard Li-Ion that lots of people use.

18500 is a less common Li-Ion that is fatter than a AA, but just as long.

14500 is AA size

10440 is AAA size

16340 is CR123 size.



I'm thinking maybe two 10440's in series? That would pump out about 1600mAh at 3.7V, right?
Ari-Jaq Xulden
10-24-2010, 07:19 PM
If your going to run two in series I suggest the 18350.
RevengeoftheSeth
10-24-2010, 07:42 PM
They are too wide to fit side by side and too long to put end to end.
Sunrider
10-24-2010, 08:08 PM
can you say run time?

http://www.dealextreme.com/details.dx/sku.5035
RevengeoftheSeth
10-24-2010, 08:24 PM
LOL that might actually work. It would just barely fit in the 1" PVC tube. I don't know if there would be room for wires around it, though.
cardcollector
10-24-2010, 09:25 PM
Remember, you can always stack another battery on the top of your sound board. IMO you have a lot of space left, it is just filled with hot glue:) I have fit the same components in 2.5" of space in a 1.25" sinktube. Tricky, yet possible.
equinox13
10-25-2010, 12:00 AM
2 notes on that 25500 battery.

1 - it's not protected so you'll need a PCB for it.
2 - it looks the same size as a C cell so if you have one of those lying around you can test fit with that.

as for room, it looks like you have plenty of room for several AAA batteries.
RevengeoftheSeth
10-25-2010, 07:25 AM
Remember, you can always stack another battery on the top of your sound board. IMO you have a lot of space left, it is just filled with hot glue:) I have fit the same components in 2.5" of space in a 1.25" sinktube. Tricky, yet possible.

I try not to if I don't have to ;) I hate hearing that 'crunch' sound when something goes wrong, lol. I also made it specifically that length to wedge the heat sink and LED into place behind my blade-stop. I should have factored in another 1/2" though for a 18650.