So, the layout seems ready... 3 days kicad and love it :)

Well, it got a 4 layer design which fits in a the smallest Hammond 1598 series enclosure.

So the cheap 1598BSGYPBK as well as the more expensive, flame retardant 1598BBK should fit.

The schematic changed dramatically... all that 5V generation stuff did not fit since I wanted to have room to have the cellular stick mounted inside the chasing. On the other side, I would have needed a second PCB for the batteries in any way. Now this will have to hold some 5V generation stuff and the lithium battery as well...

I'm not totally sure if I will opt for parallel or series battery connection. If I go for the parallel connection, there's no need for the lithium batt but that high currents bother me...

This thing has 7(!) USB port + maybe a RPi3... so that's 3.5A for USB + another 1A for the Pi at least... so 5A@5V makes roughly 10A at 3V (including the efficiency of the converter)... well maybe it was a good idea to split these problems ... at some point a charging circuit would be very nice...

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