Batteries


Batteries, those unspoken champions of our modern, mobile age.

Take away these tiny heroes and our world would be so very different – especially for us bloggers. But where did we get them, and how do they work?


Let's find out.


A shocking development

We've all been there. You walk up to somebody and, as soon as you both touch, a shock is felt. This is one of the first experiences mankind had with electricity; the other and more dramatic is lightning.

For thousands of years, that was just about all that was known. Then in the 1700s, Benjamin Franklin wondered if electricity was a kind of fluid. To test his theory he undertook the rather dangerous task of flying a kite in a thunderstorm with a key. (Not familiar with the story, go here.)


Now we know that electricity is the movement of electrons (hence the name electron). But knowing how batteries are a source of electrons is another matter.


Positive energy

Imagine you're by a roaring fire, say in a fireplace.


The light and heat coming off show that there is a source of energy within the fire. In fact, what is happening is atoms are rearranging in such a way that extra energy goes out into the world as a free gift to all.

This energy can be tapped and used. Sometimes it is used to warm us, roast our marshmallows, or provide a romantic atmosphere. But by using this heat to boil water to make steam, other uses come to pass. Steam can be used by a steam engine, like in a steam locomotive.

Or it can be used to drive generators in a power plant to make electricity.

But there is a much more effective way to make this energy into electricity.


A more excellent way

Let's move away from fire to a more useful – but certainly a less dramatic – example. Put some zinc metal in a blue solution of a compound called copper sulfate and see what happens. What you end up with is the zinc disappearing along with the blue coloring. What's left is copper a the bottom of a colorless liquid.

What happened?


The copper sulfate is copper bonded to something called sulfate (hence the name). Here, the zinc replaces the copper and gets bonded to the sulfate, leaving the copper to settle to the bottom. The whole process is described by using, loosely speaking, a chemical equation.


The sulfate is what is called a “spectator,” it doesn't really do anything. So let's clean things up by removing this from the picture.

Notice the 2+. This is because first the copper, then the zinc, are positive "ions" – their atoms are short two electrons from what they usually are – hence the 2+.


Now rethink this reaction as being in two parts. The zinc, you will notice, went from ordinary zinc to zinc that is short 2 electrons. In other words, the zinc atom loses two electrons.

For its part, the copper went from being short 2 electrons to being normal again. Again, this is just a copper ion picking up two electrons.


So far, all we've done is to take a chemistry reaction, cut out the non-players, and break things into pieces.


Now for the brilliant part.


Remember that this reaction has energy we want to use. Also, remember that electricity is just the moving of electrons. So physically break up the two halves of this reaction with the zinc and copper separated and let the electrons be the electricity.

This is called a galvanic cell. The same reaction is still happening, just in two different places. The result is that the zinc metal has extra electrons, while the copper ends up with not enough. When a wire connects these two metals (such as in a flashlight, phone, mp3 player, and so on), the electrons can move – we have electricity – and carry the energy with it to whatever device it's connected to.


We have a battery. Of course, the inside of batteries looks a little different than the picture, but it's still the same idea.


She sells fuel cells

Before moving on, a brief word about "fuel cells." Fuel cells are similar to batteries and have a similar idea. The difference is that instead of having two metals sitting in a solution, the fuel and a source of oxygen are fed into the cell, which then uses it to make electricity. When astronauts went to the moon in the 1960s and '70s, they used fuel cells that used hydrogen and oxygen to provide electricity to the astronauts.

People are currently working to make a fuel cell that uses gasoline, like what we use in our cars now, making electric cars far more useful.


Reaching out

Batteries are so very valuable to us in many ways. For the first time, with the battery, we could produce as much electricity we want for as long as we want it. This was very important to scientists who could study electricity in greater depth. What was learned was that there are other ways to make a positive and negative to give electricity.


The generator was born. With it, we have a source of power in our homes.

We have the power to keep our car engines running.

And electrical power from the wind.

And more recently, we have solar power – a light battery.


But regardless of where the power comes from, chemicals in a battery or a generator in a windmill, the end goal is always the same. Take some available energy source and efficiently transfer it to electricity so that it can be put to use whenever, however, and wherever we want.


That is the miracle that batteries have given us.


Great books

Twenty Thousand Leagues Under the Sea

A classic story written by Jules Verne. It is 1866, and ships begin seeing what seamen describe as a sea monster. The famous French marine biologist Professor Pierre Aronnax agrees to help the United States navy find this monster. Their ship, the USS Abraham Lincoln, encounters the "monster," and in the resulting battle the professor, his assistant Conseil, and harpooner Ned Land end up overboard and end up finding this "monster."


To their surprise, the monster turns out to be a battery-powered submarine called the Nautilus under the command of Captain Nemo. They travel in this submarine for a distance of 20,000 leagues (60,000 miles) before ending up leaving the sub.


Note: In the Disney movie version the Nautilus is atomic-powered. In the book, it runs on a lithium battery.


On the web

Batteries and How They Work || BURN Radio

A video explanation of how batteries work.


How to Make a Lemon Battery and a Lime Light

You can make a homemade battery using a lemon or any citrus – 'tis a classic science lesson. This video shows how to do it.


World's Largest Lemon Battery- Lemon powered Supercar

A couple of guys build the largest lemon battery in hopes it can power an electric racing car. It failed, but they have a lot of fun in the process – making this a fun video to watch.


POTATO BATTERY: Make your own

Why should citrus have all the fun? Make a battery out of a potato.


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