How do you charge a camera battery without a battery charger?

It can be dangerous, but it is possible. I have lost chargers and had to do it. But I wouldn't recommend it unless you pay close attention to it. The way I do it is I take a phone base. (A cordless phone base). I have 2 pieces of tin foil. I fold both pieces of tin foil so you have 2 long skinny pieces of tin foil, I then place each piece of the tin foil on the metal charging pieces of the wireless phone base. Then place one piece of tin foil on the - and one piece on the + of the battery. I then tape the tin foil to the battery and let it charge. Make sure you pay close attention to the battery so it doesn't over charge and start a fire.

Also, if you have a computer, you can take a USB cord and cut off the part that you would connect to a device (not the USB piece) then carefully separate the red wire and the black wire from the rest, Remove the casing from the wires. Place the red wire on the + on the battery, and then place the black wire on the - on the battery, then tape it on and let it charge, pay close attention, if it gets hot then you did something wrong and immediately remove the battery.