Use your urine to make electricity! With the pee battery you can make enough energy to power a small electric motor. It is quite an easy project without the use of dangerous chemicals! All you need is

an empty aluminum can (e.g. coke can),
a piece of copper,
vinegar,
crocodile clips
and urine

Following tools are handy for this instructable:

steel wool
can opener
electric drill

Step 1: Open the Can

Remove the top of the aluminum can. Use a can opener.

Step 2: Remove the Coating Inside the Can

Cans have a coating inside. You need to remove it.
The easiest way is to scrub it using steel wool.
By using an electric drill you can get this job done faster.

Step 3: Set the Battery Up

First, add urine to the can. The urine will act as electrolyte.
Second, add vinegar to the can. The vinegar will boost the voltage as it adds more acid to the electrolyte of this battery.
Third, put a piece of copper in the electrolyte. Connect it with a crocodile clip.
Finally, connect a second crocodile clip to the can. Make sure it touches the inside of the can.

Step 4: Power a Small Electric Motor!

The aluminum of the can is the cathode, which is the negative terminal.
The piece of copper is the anode, which is the positive terminal.
The urine in the can is the electrolyte.
Now chemical reactions inside the can create opposite charges on the copper and aluminium can, but the urine prevents the charge from flowing.
If you connect a motor to both crocodile clips, the charge flows through and powers the electric motor!

I hope you have enjoyed my instructable!