Conserve energy, disregard the use of batteries and battery operated machinery and opt towards change. Now you can start at this path by choosing the flashlight that will work on water. There are many harmful chemicals inside these environment-unfriendly batteries, which when disposed in open can leech out and pollute the soil or water that they come in contact with.
Pack your flashlight stash for those camping trips or for emergency situations when the power runs out, you can never be too prepared. This easy to make flashlight offers satisfactory performance with an alternate resource to derive its energy, with a galvanic cell which passes a galvanic current to make it work, it can work continuously for 30 minutes on tap water and for 2 hours with salt water.
Here is what you will need
Planning to go green this summer? Then the DIY flashlight that not only is easy to make but miraculously runs on water, is a perfect first project. Before you start you will need some basic things at hand, these are:
Aluminum foil sheet
5mm white LEDs
2N3904 General Purpose Transistor NPN
1 K Ohm resistor(1/4W)
Copper and zinc strip
Magnet or copper wire
5 sheets of toilet paper
2 x 2” sheet of acetate
Teflon Tape, Glue
Get started with the project
First cut the strips of aluminum into tiny round traces. This will be your cathode for the homemade battery. You can also choose zinc to be the cathode too, but because of their easy availability and better chemical configuration aluminum is what most people chose to go for.
Using the just cut aluminum traces as guides cut tissue into tiny traces. You can also choose to cut these into wet wipes which are easier to manipulate and have higher tear strength than regular tissue paper or toilet paper.
Now you need to stack two sheets of wet-wipes/ tissue traces over your coins and place a sheet of aluminum over these two tissue traces. Keep on repeating and stacking these one over the other till you do it to ten pennies.
Glue the coins together to complete your galvanic cell.
You can check the battery to be operating by connecting it to a voltmeter.
Take the recycled torch and drill through its plastic to provide for entry and exit points for the fluid. Without an exit for the excess fluid the flashlight will short and not work.
Place plastic dividers in between the enclosure to place the penny-battery.
Place the home-made battery inside these plastic dividers and sprinkle salt over the cells. A galvanic cell works on fluid and ionic exchange. This salt can work wonders for your water-powered flashlight
Glue in a switch with your batteries and place it on desired position.
Take a tiny piece of a perfboard and install the LEDs
Build a Joule thief Inverter from the things you have to keep the batteries from running all out.
Waterproof the electronics by sprinkling hot glue over them. This will prevent unwanted damage from the salt and water from harming your assembly
Put the cover back on and attach the pipes for the water from the entry and exit points.
You can now test your creation!
To create a battery-free Water-powered flashlight with your bare hands all you will need is our set of instructions, handy tools available and some inspiration.