Halloween costume #2: Phoenix! Isis wings running @Mark_Kriegsman 's unstoppable Fire code. (I had a gig at a silicon valley tech company Halloween party, and they were all delighted to geek out about the wings with me, so that went well)
Also my battery lasted TWO FULL HOURS. I am happy with this.
Looks really good. What voltage/capacity/type of battery were you using? Looks like you were driving about 110 LEDs.
Erin, your costumes are super!
Just amazing. I made a wearable fiber optic tufted spinal column for a friend, 64 LEDs…I found a 15000mAh Limefuel pack. Easy 8-10 hours, still pocket sized, 4 amp combined output…
What battery did you end up going with?
@Garrett_Mace
Can you put those powerbanks parallel with eachother? To support 8Amp or a longer time?
@Kasper_Kamperman NOOOOOOOOOO!
Argh twitch
Sorry. Having flashbacks.
Trust me, for I burnt about $120 in Limefuels to bring you this information: You can not wire the outputs of Limefuel battery packs in parallel. Not even two outputs from the same pack. They will die. You have to split your power bus and tie the negative rails together, but keep the positives separate. I have tried this, and it works.
But it’s shitty as you end up with lots of little power buses. I have a mad-scientist scheme involving carrier-grade communications rack 20A/5V DC-DC converters and frightening remote control car Lipos that will give me a 200W wearable, but haven’t been crazy enough to try it yet.
@Robert_Atkins Thanks for this hard earned information. Any powerpack brands that you recommend? Limefuel is not available in Europe. Do you have suggestions available in Holland?
Nothing else I’ve used except for cheapies from Hema. Note that the problem about connecting outputs in parallel isn’t specific to the Limfeuels, you will probably have the same problem with any brand.
What are you intending to build? I have opinions on wearables 
Well not really a wearable, more a product that I’d like to be able to run standalone. I will use 132 leds (maximum 8A) and don’t want to put the brightness down too much. However not all the leds are on all the time and I use very saturated colors. It’s not directly a need, more an interesting option. The problem is that I don’t like to split up power (it’s doable, not preferable).
Take a look at something like this, hooked up to a sealed lead acid battery: http://m.ebay.com.au/itm/DC-DC-Converter-Regulator-12V-Step-Down-to-5V-20A-100W-au-/270781055660
Ok, and 12V is better because you’ll have more power I think (so longer duration)? I also come across 6V lead acid batteries.
If you are running full-white and pulling 8A @5V, that’s a maximum of 4A @12V(fudging the math, but you might lose some in inefficiencies in the DC-DC converter) which will give you a bit over an hour on a 4.5Ah 12V SLA battery (http://www.batteryspace.com/SLA-Battery-Sealed-Lead-Acid-Battery-12V-4.5AH.aspx). That’s a pessimistic estimate for full power (the converter will probably be more efficient) and if you factor in only drawing about a third of that as you would for an unsaturated rainbow pattern, I’d guess you’ll be good for around four hours.
If that isn’t enough you can always get a bigger battery. You could run it for a week off a car battery 
Oh, there’s also these guys, which look pretty awesome: http://www.illumn.com/pv-devices-drivers-accessories/murata-okr-t-10-w12-c-dc-dc-converter.html
(If only they had an over current/under voltage cutoff built in!)
I am using an 11.1V 2200mAh LiPo battery … One of the scary RC Car ones. It’s in a little backpack lined with several layers of flame retardant cloth.
I don’t actually know how long it will run the wings (I have 120 neopixels) because if you run these guys too low they just quit recharging and you are out $25. I used to have a little LED display thingy I can plug in to the battery that would beep when the voltage got dangerously low… Gotta get another one. But after 2 hours running mostly Fire on 50% brightness I still had lots of volts left.
Dammit. I need to build a reference design with one of those Murata 10A DC-DC converters and a 3s Lipo protection chip :-/.
(If I’m not careful I’ll end up as a real EE!)
Those Murata’s are insanely expensive, but to get 10+amps is what the LEDs need.
I thought they were pretty reasonable—USD$15 on http://illumn.com and $8 or so from Mouser.
We’re benefitting from the availability and competitive pricing on these because they’re popular with the e-cig/vaporiser modders.
@Robert_Atkins I thought you were talking about these guys: http://www.mouser.com/search/refine.aspx?Ntk=P_MarCom&Ntt=161534838