Black and Decker USB charger

thingiverse

Update: The Black and Decker batteries do not automatically cut power when they are too low. That is done in the tool. Be sure to add some kind of voltage monitor, cutoff circuit, or just make sure you don't use it for too long. I made mine out of ABS and super glued the parts together. There is a lot of room for improvement but it works! I used these for the 20v to 5v regulation and USB connection. https://www.amazon.com/gp/product/B01HXU1C6U/ref=ppx_yo_dt_b_asin_title_o05_s00?ie=UTF8&psc=1 I used crimped on spade connectors that I had lying around and press fit them in for the batter terminal connection and soldered on some short wires to the input of the regulator.