Penny battery

Mother Earth Monday – Penny Battery

Penny battery

A bit of light change.

It is funny how often we rely on pretty toxic materials for some of the most minor things. We put our eco-friendly water in utterly non-eco-friendly plastic bottles. We coat ourselves in a toxic cess to ‘wash’ our hair and of course we light our low energy LED flashlight with Lithium batteries. Sometimes, it is really not so big a deal to manage something with far less toxic means. Thinking of this, I decided today’s post would be something to demonstrate just how easy it is to go with a low toxic means of doing things with junk laying around our house and some household products.

Just for fun, let’s play with making a battery. Why would you ever need to do this? Well, beyond this thought experiment, you probably never would if we are being honest. That said, it is good to understand how very simple it is to create a non-toxic battery. It can do the minor tasks that we keep putting lithium batteries into our toys for.

First, you are going to need to find a few pennies. Look or pennies that are 1983 and older. There are some versions of this experiment out there that list 1982, but that was the year they were transitioning to roughly 98% zink in a copper sheath and some pennies from that year will still be too high in copper. Ten pennies is generally enough to easily power 2 LEDs and 6 can power a cheap calculator. Sand off one side of each penny so that one side is silver and the other is normal. This can take a while unless you use a sanding device. You can bypass the need to sand them if you buy a number of zink washers equal to the number of pennies you plan to use.

After all of the pennies are ready, cut bits of cardboard and trim them down so that they are roughly the same size as the pennies. Dunk these in cup of vinegar and allow them to soak. Lemon juice or saltwater can be used as instead of the vinegar. The better you trim the cardboard before soaking them, the easier it is to keep them separated later which is important for proper functioning of the homemade power cells. Alternatively, you can fold up bits of paper towel to rest between each penny as seen in the picture.

To create a cell, place a penny with the silver side down and copper side up at the bottom. Next place a vinegar soaked bit of cardboard on top of that. Repeat the process until you have used all of the pennies. If you are using zink washers, start with a washer, then cardboard, then a penny, then a washer and so on. Each combination of penny and cardboard is a single ‘cell’ and will generate roughly .5 volts of energy. After all of these have been stacked, attach the wires from either end of the circuit you intend to complete. This can be the ends of the LED wire or the wires from the calculator. Remember that the copper side is the positive side of the battery.

To hold it in place, wrap it tightly with electrical tape. If you surround it entirely, it will slow the loss of moisture which allows the battery to function longer. Since this is a wet-cell battery, it can be reactivated if you can reapply vinegar to the cardboard. Even so, it will generally last several days of continuous use. In theory, you don’t want it completely airtight since evaporation is part of what causes this to work.

One final note is that this is not illegal. While it is illegal to deface money with intent to commit fraud, this does not qualify. The US Mint has even put forth their own version of this battery in lesson plans for children. The alteration of coins is illegal if, and only if, you intend to do commit fraud. Altering it for other causes isn’t going to land you in jail or gain you any fines. With that out of the way, go forth and play. Maybe some day when you are facing down the zombie apocalypse or otherwise in need of batteries without any hope of having them handy, you will find a pocket full of change and an old bottle of vinegar and manage to build a working LED Flashlight to get by with. Then again, maybe you will just tuck this away never to be thought of again. Who can say.

What are your thoughts?