Sorry, I am new to thingiverse and should have posted it as a remix. The remix is here: https://www.thingiverse.com/thing:3707719
A remix of the excellent fume extractor that added space (14 mm) to the bottom for the addition of rear micro USB port, 18650 rechargeable lithium battery, lithium charging board, and boost converter. Overall, an extremely tight fit. Now my fume extractor can be used untethered from cables!
I tried a much as possible to maintain the original aesthetic by rdmmkr.