Raspberry Pi 3 and Display over battery?

The easiest way is a battery pack for charging mobile phones. Just make sure the port can handle at least 2 A or more .

I use a power bank to drive the Pi3, 15.6" USB powered HDMI screen and a USB powered audio interface with 48V phantom power for microphones.

BUT, you must use the shortest USB power lead you can get (10cm or less... yes, that is 100mm or less). Even the short curly leads provided with the power banks are too high in resistance to avoid voltage problems on a Pi 3. The current output of the power bank is largely irrelevant unless you want to put a load on the Pi approaching its maximum rating. That might be the case with USB powered external hard drives or USB powered DVD writers.

Wow! A 15.6 inch USB powered hdmi monitor? Thats quite cool! Unfortunately I'm planning on using an eBay LCD that will probably have a 12v requirement. So I need to find a way to supply 12v (ish) to the display driver board, and then step it down to 5v for the Pi. I also need a charge circuit for said battery. But thanks for your reply, and it would be great if you could link me to that sweet monitor!

https://www.amazon.com/GeChic-2501C-Portable-Monitor-Inputs/dp/B00H4MWMWQ

This appears to be one. I googled  15.6" USB powered HDMI screen

that I copied from your message and found a bunch of them here in the US.

Mike

Even though the monitor is rated for 12V there is a good chance that it could work off of something like a 7.4V battery pack. Then you would need to step that 7.4V down to 5V and 3.3V for the Raspberry Pi. The Ben Heck show did an episode on making a portable Raspberry Pi that you might find helpful.

Your avatar is awesome. May the force be with you.

Thank you.

Mike

That covers the 5V but not the 12. but the addition of a low cost Boost Convertor should fix that. there are many available, just ensure it has the power to drive the display.

Using 3 LIPO in series will give you the 12V you require (Or close enough), using a cheap 5V buck converter (There only a few $$$) to efficiently drop the 12V to a 5V supply will power the PI

There are chargers that will work with this

You dont say how long you need this to run on batteries or what power the display will require so it is hard to be more specific

I have not used one for this purpose, but I have found them very cheap and effective ways to generate 12V at quite high powers from a 5V supply. They are tiny - about the size of a thumbnail.

Getting the 5V out of the power bank and into two wires to the converter is a challenge. Some power banks come with a usb to standard round power connector cable. It is an easy task to get the matching socket and solder it to a bit of strip board. Look for a power bank with two USB outlets.