Battery For Wearable Electronics

Hello Everyone!
I am in the process of designing a new wearable LED shirt. I'm been thinking about how I'm going to power it, and ordinarily I might use something like this:

however, those lithium polymer batteries only have 3.7v, and the LED modules I'm using really would like 5v (they'll work with 3.7, but they'll just be dimmer). The other issue with some of those LiPo batteries is that they have small capacity and can't necessarily handle a huge current draw. Is there any reason you guys could think of for why I wouldn't/couldn't/shouldn't just use something like this:

http://www.amazon.com/Compact-10000mAh-Portable-External-Technology/dp/B009USAJCC/ref=sr_1_5?ie=UTF8&qid=1417989836&sr=8-5&keywords=anker

A portable charging pack? It has a huge capacity, has USB power which makes it pretty easy to deal with, is rated for high current draw (upwards of 2A on some of them), and is 5V at the output. In fact, I have one of these that I use when I travel and I just plugged it into my old LED shirt and it seems to be powering it just fine... I just wanted to run this by everyone here since I've never seen this done before and perhaps I'm missing something?

Thank you in advance,

Chris

I have used the USB rechargeable battery packs with portable Arduino projects and they work great. I also use the Adafruit PowerBost cards with 3.7V Lithium Ion Polymer batteries like this:

These little batteries work good with wearables. They are small, light and seem to have enough power to last a long time in my wearable projects.

Adafruit has several PowerBoost models, some with chargers, so look around.

Dave

GunnerCAF:
I have used the USB rechargeable battery packs with portable Arduino projects and they work great. I also use the Adafruit PowerBost cards with 3.7V Lithium Ion Polymer batteries like this:

https://www.adafruit.com/products/1903

These little batteries work good with wearables. They are small, light and seem to have enough power to last a long time in my wearable projects.

Adafruit has several PowerBoost models, some with chargers, so look around.

Dave

Thank you Dave! I didn’t know about those boosters, so I’ll check them out!

Chris

Hello Everyone!
About two years ago I made a cool RGB LED shirt, here's a picture of it:

This shirt has served me very well, and I've had some great times in it:

This design was very simplistic, and was put together quickly. Unfortunately it suffers from a few problems, one of which is poor connections (they keep breaking off, in fact you can see a broken black power wire in the picture above, that happened last night). I learned a lot while making this, and I think I'm ready to make v2. My plan is to use the Adafruit FLORA and the Adafruit FLORA RGB Neo Pixels. I'd like to have a 5x5 grid of them on the front of the shirt (and the back, but perhaps that's v2.1). I realize that 25 of these things at 60mA a piece is 1.5 amps, so current draw and and a power supply are going to be critical design parameters. I wanted to query the forums here with a proposed design and see if anyone had any comments, suggestions, criticisms, etc.

Below is a picture of the proposed design. To handle the current draw, my plan is to use conductive fabric as a power bus, and then conductive thread to branch off the power bus to each LED. I also want to use conductive thread as the signal lines going to each LED. What are people's thoughts on using the conductive fabric as a power bus? How reliable is it? Does it corrode/oxidize? Can I iron it onto a shirt? Can I iron it onto a polyester-type shirt (an athletic-type shirt, which is what I plan to use for this)?

On the FLORA webpage it says that adafruit spent a lot of time on the power design for it, and it can drive up to 50 neo pixels on its own. I plan to take advantage of this (not that it really matters, as I can simply hook the battery directly up to my power bus). However, I can't tell from the FLORA webpage, but does it have a 5V regulator? I'd like to use a LiIon, or LiPoly battery for this project, but they only supply 3.7V, which will limit my brightness. Am I stuck with this? Or does the FLORA have a regulator which will allow me to get full brightness?

At any rate, here's the proposed design, please throw darts at it (if you want to)!

Thank you in advance!

Chris

I'd be worried about getting zapped by your skin being the conductor between the 2 supply lines.
With neopixels, the cards are really intended to support wiring board to board, with power added to end of the chain also as all that would be needed. Don't overcomplicate it.

And please don’t cross post.

chrisab508:
Is there any reason you guys could think of for why I wouldn't/couldn't/shouldn't just use something like this:
http://www.amazon.com/Compact-10000mAh-Portable-External-Technology/dp/B009USAJCC

One reason is that they are lying about the capacity. You will get nowhere near 50 Watt Hours (10 Amp Hours at 5V) out of it. Probably more like 2,000 mAh at 5V.

In terms of boosters, be sure to test them. Some of them can get quite hot.

In terms of using USB battery chargers, I've had some that will only deliver more than 100mA if it is charging smartphones that set the resistance in the D+/D- pins in the usb cable appropriately, and some that go to sleep if not enough current is drawn (usually not a problem with LEDs).

You might think of 9v batteries with a step-down (buck) converter, but in practice those batteries don't last too long (they are made for smoke detectors to draw a little power over a year's time, not for LEDs consuming quite a bit of power).

FWIW, using 32 Adafruit neopixels (2 16-LED rings), and keeping the power level down to a max. of 30 for the sum of red, blue, and green power (which draws about 75mA of power), I was able to run on a 1200mA li-po battery for over 24 hours (processor was a 3.3v Gemma).