I have had luck using this USB DC 5v to 12v adapter, exclusively charging my superbook for the last several weeks. It does require a high quality USB port, low end battery banks will not charge the superbook.
I have also only used it with Power delivery turned off, not charging a phone.
It also needs a barrel adapter (5.5mm x 2.1mm to 3.5mm x 1.35mm)
I have not measured how long it takes to charge.