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I'm making a fancy dress costume for a couple of festivals coming up.. will include a few 12v LED strips, like [url= http://cgi.ebay.co.uk/2-x-48-LED-Linear-Flexible-Strip-Car-Lights-48cm-White-/120612584303?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item1c1511fb6f ]this[/url]..
My question is regarding power supplies.. need a portable 12v battery which will last for approx 4 hours to approx 5 or 6 of these led strips.
I was thinking of 8xAA batteries in a battery holder (will this be enough to power it?) - or is there a better option?
Just want something fairly small and reliable that'll keep the LEDs lit - cheers in advance
Or maybe something like [url= http://cgi.ebay.co.uk/Portable-12V-Li-ion-Rechargeable-Battery-Pack-4800mAh-/170535032613?pt=LH_DefaultDomain_0&hash=item27b4ae1725 ]this?[/url]
Any thoughts, cos I don't know much about electronics?!
I can't see a power figure anywhere on the lights but 8AAs should do just fine (you'd need to find out/measure/test the power needed to be sure).
I wouldn't use the lithium pack to power flamable costumes personally. Actually I'd include a fire extinguisher in the finished ensemble for AAs...
without knowing the rating of the strips then it's difficult to know.
those cheap Chinese LEDs don't tent to be terribly efficient.
I'd start with 8 (non rechargeable) high capacity AAs and see how you get on.
If you use rechargeables you'll need 9 cells i think as they are lower voltage
Thanks guys - much appreciated - will give it a go with the AAs and see if they last long enough.
Re: fire risk - alcohol will be involved, so no doubt I'll be fine!
If you use AAs then at least you can take a spare set with you if you need more power. With that battery pack you'll need to plug yourself into the wall for an hour or so.
looking at similar products they seem to be about 6mA per LED so that would make each strip about 290mA.
6 strips gives you 1.74A
4 hours means you'll need about 7 Amp Hours
I [i]think]'[/i] that standard AA batteries have a capacity of about 2000mAH
my problem is now working out a multi cell calculations. i think that at 12V and 8 cells the capacity will still be 2000mAH only at 12V not 1.5V
in this case i'd expect the batteries to last about an hour and three quarters
I may be very very wrong though and the LEDs may turn off before full discharge as the voltage will drop
Thanks Michael, much appreciated! I might tone it down a little and use 24 led light strips, which should hopefully give me the extra run time. 2 battery packs should then cover it hopefully..
Thanks again guys.. will no doubt be posting again in a while when I'm having problems!
Cheers
Joey
You might find your LED's will run from 9V batteries.
Maplin also stock Slimline 12v lead acid batteries for emergency exit signs. Stored in a bum bag one of these would run your LED's for Days!
Electroluminescent wire?
Re: fire risk - alcohol will be involved, so no doubt I'll be fine!
No worries then. Take a camera on the off chance 😉
Here's the end product. Still in one piece, and didn't catch fire. Next stop 2000 Trees Festival.
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