What can you do with an old cordless drill? Turn it into a DC generator. 

A lot of comments here seem to be completely missing the point. This is the foundation for an idea, not the end goal. Connect the drill to a water wheel or wind turbine or something else that produces rotary torque and use that to charge batteries. You can get a cheap drill for like $20 at walmart or something, or find used ones online that people are trying to get rid of. A motor and a generator are mechanically the exact same machine, converting rotational energy and electrical energy back and forth.

That's pretty cool thanks I'm going to try making something

Thanks this is just what I needed. Btw it would be cool if you put regenerative braking in the tags!

Same as the other guy! Watched your superhero video and now you got yourself a subscriber! :)

Get a vice my guy

you can take the motor out and put a train horn with a tiny compressor

What will happen if you flip the planetary gears around to step up the speed of the motor?

Now make it functional!

Just watched your superhero vid. That was cool. This is cooler. Also my first time being the first commenter- heh

Take the motor out of the drill before you install it on your windmill. 86 that clutch assembly its not geared right.

So you chuck one cordless drill to the dead drill, then connect the dead drill to another drill. Then you run the first drill that turns the dead drill that powers the third drill. And you drill a hole. Whew that was toooo easy.

Wouldn't the drill in theory, eventually charge its own battery????

No words

You can use this to charge a cell phone

Bruh

I thought of an idea where an electric car can have almost unlimited mileage. Simple...on paper at least. Have 2 battery banks. Switch between the 2. Run one, charge one. When I e gets low, switch them and charge the other one.

Not useful !