My portal gun kept running out of juice! Rather than go through galactic customs, I printed off this wireless charger.
Grab the inductive charging set, plug, and power supply from Adafruit:
The receiving charging coil goes in the portal gun (in the circular inset on the model), and gets soldered to the input of the LiPo charging backpack.
The other charging coil goes into the base (in the circular inset). Attach the panel mount barrel jack to the back of the base, and solder up the wires.
The charging coils need to be pretty well aligned to work, so make sure you fix them in place. I used a dab of hot glue.
That's it! Plug in your power, and plug in the portal gun! Wireless charging is the future!