To confirm 250 LEDs (mix of WS2812, APA104 and i think one WS2011) need about 4a (or is it 5a?) They run on 5v just like my arduino nano. Where can i find a 5v battery that can give me at least 5v 3a or 5v 4a or even 5v 5a? Can i string up multiple batteries? What about AA batteries? i have a thingy that can hold 8 AA batteries and a step down thing that converts 12v to 5v, would that give me enough power? At i brightness of 55 i was able to run all 250 LEDs from my 2wire 5v 2a plug in wall powersupply which confuses me on whether i actually need 4 a?
At full, bright white you’re looking at more like 12-15 amps (at 5 volts). The specs for those lights typically call for 60ma for full white. I don’t know if there’s any linearity to the brightness/current demand, so you might have to actually measure the current draw in order to determine how bright you can go for any particular available current.
Draw is fairly much exactly linear, and typically 0.06A/LED @ 5V. Yes you can use a 12V to 5V DC-DC converter, but you probably don’t want to draw more than its rated current from it. Also be aware of voltage drop, especially when you’re pulling lots of amps at low voltages.
I use single cell LiPO batteries to light up my remote projects. The batteries provide up to 4.2 volts at full charge and you should stop using them when voltage hits 3.0 volts (discharging beyond 3.0 volts can damage the battery). LiPO batteries can provide bursts of current many times rated capacity. Here is a link to the batteries I use. You will most likely want a LiPO rated charger and the tabs on these batteries is aluminum - so you will need aluminum solder paste.
http://hobbyking.com/hobbyking/store/uh_listCategoriesAndProducts.asp?idCategory=317&LiPoConfig=1&sortlist=H&CatSortOrder=desc
I have used multiple 12v batteries with 12v to 5v converters in parallel. You can pull more amps and have more capacity.
i like the @Royce_H idea
Lipos are an awesome power source when you want high amps in a compact package. As Michael Shanet says, you don’t want to discharge them all the way. You can get a cheap alarm for a couple of buck on ebay.
The batteries I use don’t allow you to discharge all the way. They internal circuits that cutoff at a certain voltage.
Even better! I already have a few lipo’s that I use for quadcopters without an automatic shutdown (otherwise quadcopter “fall go boom”) so those are the ones I use for other electronic projects as well. That being said, just bought a “Universal 50000mAh Backup External Battery 2 USB Charger” off of eBay to try it out. Off topic… does anyone know if FastLED can run WS2812 and APA104 addressable LEDS at the same time?
As far as i know i think so because i’m running a mix of those strips.
Would i be able to draw 4 amps out of a battery like that?
This should tell you what you need to know…
Interesting. I’ll stick with aa batteries this time and lower the brightness because I’m making this for someone so I don’t trust them with a Lipo but I might use them on my friend snow board project