The lipo powered raspberry pi box on the latest Know How was interesting, but do you have to disc...

[G+_Jason Kirk]

The lipo powered raspberry pi box on the latest Know How was interesting, but do you have to disconnect the battery to charge it? I'd like to be able to plug in the box, running the Pi and charging the battery, and when unplugged it'll run off the battery without having to power the pi down and up. Can I connect a power supply in parallel to the battery so the pi will run off the battery if power is lost or better yet, charge the battery as well. Also any way to detect when the external power is lost to have the pi to power itself down nicely or detect when the battery is running out of juice?

[G+_Travis Hershberger]

You mean something like http://www.adafruit.com/products/1944 or http://www.adafruit.com/products/2465?  I've used the 1A for a project and it works well.  I don't know if it will send a signal to initiate shutdown or not.  Frankly I'd be surprised if someone hasn't written a script for that already if it's not built in.

[G+_Travis Hershberger]

Fr. Robert Ballecer, SJ solution is cheaper, but you do have to disconnect the battery to charge it.  His solution is a great for $4, while those adafruit power controllers run $15 and $20.

[G+_Jason Kirk]

Cool.  Thanks for the info.

[G+_Jeff Brand]

I don't think it was said out loud but the solution works for 2S+ batteries. For those of us looking to use smaller 1S (3.7V), this is something I'm about to try: http://www.amazon.com/gp/product/B00C93Z8JY

 

My intended use will be for Pi/Quad setups where the Pi needs to live for about 30 minutes max.

[G+_Jeff Brand]

Also, Fr. Robert Ballecer, SJ, I've read that the "best" voltage is 5.2V. I don't know if that's only in spec for USB power and not through GPIO. Adafruit products tout this as a way to prevent undervolting during moments of high draw while doing no damage to the hardware.

[G+_Jason Kirk]

Yeah, I got a usb wall adapter from Adafruit for a raspberry pi that made a point of being 5.2V