Posted in home hacks, Tool Hacks Tagged battery, buck converter, emergency, inverter, power tools, rechargable, ryobi, switch mode power supply Post navigation Is there a better way that’s as easy and adaptive (you don’t have to alter the devices you’re powering) as this one? We would like to hear your thoughts on this technique. We think it’s a nice touch to include LED feedback for the battery level.

The hardware is housed inside of a scrapped charger for the batteries, with the appropriate 3-prong socket hanging out the back. After regulating down to 12V he feeds the output into a “cigarette-lighter” style inverter to boost back to 110V AC.

The final iteration, which is pictured above, builds a house of cards on top of the buck converter. We really like see the different solutions he came up with for interfacing with the batteries which have a U-shaped prong with contacts on opposite sides. The device steps down the ~18V output to 12V regulated for devices meant for automotive or marine. His next autodidactic undertaking carried him into the realm of switch-mode buck converters ( learn a bit about these if unfamiliar). That’s because he prototyped a way to use power tool batteries as an emergency source - basing his circuit on a 7812 linear regulator which got piping hot in no time flat. And like most of us have done at least one, he managed to burn his fingers on a regulator in the process. Took matters into his own hands after experiencing a days-long power outage at his house.

Power drill battery