How Do Batteries Work? (+DIY Homemade Battery)

Batteries are everywhere. They are in our phones, tablets, laptops, cars, mp3 players, toys, flashlights, clocks, wristwatches ..... And still, most people don't even know how a battery works. In this Instructable you will learn how a battery works and also how to make your own battery. Let's start with the history of batteries

Step 1: LEARNING: Battery History

The first battery, called the Voltaic Pile, was made in 1799 by an Italian physicist, Alessandro Volta, by stacking layers of zinc, brine-soaked pasteboard or cloth, and silver. This was not really the first device to produce electricity, but it was the first to give a steady, lasting current.

Another battery, called the Daniell Cell, was made in 1836 by an English chemist, John Frederick Daniell. In the Daniell Cell, there is a copper plate, which was placed at the bottom of a jar and a copper sulfate solution was poured over the plate half-filling the jar. Then a zinc plate was hung in the jar, and a zinc sulfate solution was added. Because the copper sulfate solution is denser than zinc sulfate, the zinc solution floated on top of the copper solution surrounding the zinc plate.

By 1898 a company called, National Carbon Company, made the Columbia Dry Cell, which became the first commercially available battery sold in the U.S. National Carbon Company, later became Eveready Battery Company, which produces the Enegizer Brand

Step 2: LEARNING: Battery Structure

Even though there are many different types of batteries, they always have these main parts inside: a cathode, an anode, a separator, an electrolyte, and a collector.Some batteries might have more parts.

The cathode is the one that connects to the (+) positive terminal, and the anode is the one that connects to the (-) negative terminal. Between these two, also known as the electrodes, is where the chemical reaction takes place.

The separator is the one that separates the anode and the cathode from touching while the chemical reaction takes place between them.

The electrolyte is something that allows the electric charge to flow between the cathode and the anode.

Lastly, the collector is the one that conducts the charge to the outside of the battery.

Step 3: LEARNING: Battery Reaction

When something (like a light bulb) is connected to the two terminal of the battery, it completed the circuit, and the battery produces electricity through a series of electromagnetic reaction between the anode, cathode, and the electrolyte.

An oxidation reaction happens in the anode, and at the same time, a reduction reaction happens in the cathode.

During the oxidation reaction, the anode is creating electrons, and at the reduction reaction, the cathode is absorbing the electrons which the anode created.

The battery will continue to produce electricity until one or both electrodes run out of the substance necessary for the reactions to happen.

With rechargeable batteries the process can be reversed, and that happens when you charge it.

Step 4: MAKING: Homemade Battery Part 1

This battery that you're going to make is very similar to the Daniell Cell.

To make this battery you will need the following:

Parts:

a good plastic container with a wide lid (mine is a curry powder container)
two insulated electrical wires about 10cm long
an aluminium foil 5cm long x 5cm wide
plasticine

Tools:

something to strip off the insulation of the wires(i used pliers)
something to make a hole on the lid of your container (i used a hammer and a nail)
a multimeter to check the voltage (optional)

Step 5: MAKING: Homemade Battery Part 2

After you have all the materials and tools, prepare your wires by stripping off about 2cm of the insulation on both ends.

After you've done that, make two small holes, a little bigger than the diameter of your wire, on the lid of your containers about 2cm or more apart (make sure they are not too close because this battery doesn't have a separator).

Next, wrap one end of one of the wires with the aluminium foil. That will be your negative terminal.

Put each wires in each holes, leaving about 2cm of the wires on the inside of the lid (make sure the aluminium foil-wrapped end of one of the wires is on the inside of the lid)

Put plasticine around the wires and on the lid so that it doesn't leak. (you can also use hot glue gun. i think it would be better)

Make some salt water solution by pouring a lot of salt in water inside a cup or something else and stirring it until all the salt dissolves. Pour it into your container, close the lid and you are FINISH!

Check your homemade battery with your multimeter and see how many volts you get.

If you experiment with different types of metals as your electrodes and different types of electrolyte you will get different results.