Description

PDF

You need to remove the bottom cover, it's just taped on.
Afterwards you can easily access the power port and solder the + and - wire.
The small white part needs a bit of modification with a cutter.

The stand should just click to the hub, otherwise use some double sided tape.

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• Input module (12V or 15V both worked for me):
  aliExpress
  amazon
  secured with the PCB holder and 1xM2 screw
• Output module:
  aliExpress
  secured with 2xM2 screws

There is also space for a step-down converter:
aliExpress

Secured with short PCB holder
I tried to use it with a 20V PD module, to have at least 15V at the output port.
Sadly the output module does only support 5, 9, 12 and 20V.
 

The original power supply only has 14V at 1,1A → 15,4W, the nest hub needs about 2,5 to 4W in idle. You could try to use the original power supply for the output port, but it will not be sufficient for any fast charging.