Check Out The Crazily Fascinating Lemon Battery Experiment
A lemon battery experiment involves the use of a juicy lemon, copper coin and zinc nail to form a lemon battery. When four such lemon batteries are combined, they produce enough voltage to light up an LED (light emitting diode).
A lemon battery experiment involves the use of a juicy lemon, copper coin and zinc nail to form a lemon battery. When four such lemon batteries are combined, they produce enough voltage to light up an LED (light emitting diode).
One classic science experiment used to demonstrate the fundamentals of a chemical battery system is that of a lemon battery. Lemon batteries are not capable of running motors, but they have the capacity to produce a dim glow in an LED.
Mechanism
Batteries comprise two different metals: copper and zinc, immersed in an acidic solution. The copper metal functions as the positive electrode and the zinc metal functions as the negative electrode. All batteries have a “” and “-” terminal. The acidic solution in the battery is called the electrolyte. In case of the lemon battery, the acidic lemon juice is an electrolyte, and helps to break down the atomic structure of the zinc and copper metals. This results in the release of individual electrons. The flow of individual electrons is called electricity. These electrons will flow from the negative terminal to the positive terminal of the battery. The measure of force of the moving electrons is called voltage. This is the concept behind the lemon battery experiment. However, creating successful lemon batteries is not easy.
Requirements
LED bulb4 Lemons (fresh and juicy)4 Copper coins (clean)4 Nails (2″galvanized, zinc-coated steel nail)5 Alligator clip wires
Procedure
Step 1Take the first lemon and make a slit at one end. Make sure the lemon is juicy because the citric acid in the lemon acts as the electrolyte. If there isn’t enough lemon juice, your battery won’t work. Insert the copper coin into the slit. Make sure your copper coin is clean.
Step 2At the other end, make a similar slit and insert the galvanized zinc nail. Ensure that the nail and coin do not touch each other. The coin and nail form the positive and negative electrodes respectively, thereby forming the single cell of the battery.
Step 3The two oppositely charged electrodes will now permit the flow of electrons through them. The free electrons from the lemon juice will travel from the negative electrode (nail) to the positive electrode (coin).
Step 4Connect the two electrodes using an alligator clip wire. Electricity will flow from the nail to the coin, via the lemon juice electrolyte. The rate at which the electrons flow is called voltage. The faster the electrons flow, the higher the voltage.
Step 5The voltmeter will measure the rate of electron flow. If one connects the voltmeter to the electrodes, a voltage of 0.906 volts will be detected. However, this is not enough to light a bulb.
Step 6To achieve enough voltage to light the bulb, one has to make more lemon batteries and connect them via the alligator clip wires. Take the other three lemons and follow the same procedure from step 1 to step 4. Your four individual lemon batteries are ready, which if combined will give a total voltage of 3.50 volts, which is enough to light up a small, light-emitting diode or LED light.
Step 7Connect the four lemon batteries to each other with alligator clip wires, such that the positive electrode of one battery is connected to the negative terminal of the other battery. Have a look at the image above for clarity.
Step 8Connect the negative terminal of the first lemon to the LED and the positive terminal of the fourth lemon to the LED. Your circuit is complete. The flow of electrons will take place from lemon 1 to 4, via 2 and 3 and then light up the LED.
LEDs work at even very low voltages (below 2V) and low currents. These LEDs get damaged if connected to batteries over 2 volts. Thus, they require resistors to control batteries which are rated over 2V. However, since lemon batteries produce low current, it is safe to connect an LED to it. However, in this lemon battery experiment, the copper coin can pose a problem. The coin should be pure copper. One can substitute a 14 gauge copper wire for the coin. over, the coin should be clean. Have fun!
Fruit Battery Science Experiment
Fruit and batteries definitely don’t seem to be a combination that goes together. Your students will love this science experiment that has them creating fruit batteries and testing which fruit works the best. Free printables, including a reading passage, are included to help you make the most of this science experiment.
Fruit Battery Science Experiment Directions
Roll the fruit around on the counter to get the juices flowing.
Insert the piece of copper into the fruit.
Insert the nail into the fruit at least an inch away from the piece of copper. If you insert them at an angle, make sure that the pieces do not touch each other inside the fruit.
Turn on the voltmeter. If you are using a multimeter, make sure it is set to measure volts.
Touch the red wire to the copper and the black wire to the zinc. Firmly hold them still for a few seconds until the voltage stops on a number. Some meters come with alligator clips, so you could use those to clip the wires onto the copper and zinc.
Write down the voltage on your sheet and test the next fruit.
Analyze the data to determine which fruit had the highest voltage.
The Science Behind the Fruit Battery Science Experiment
Some fruits, especially citrus fruits like lemons and limes, are very acidic. The acid inside the fruit allows an electrical current to flow between the zinc and copper.
After the Experiment Reading Activity
Adding in reading and writing into a science experiment, activity, or demonstration allows you to enhance your students’ understanding and get more mileage from the activity.
For this activity, the students will read a short text that describes the science behind it (similar to what is explained above for the teacher’s reference). The students will use the details they learned in the text to explain what happened during the science experiment. They will also answer three comprehension questions using details from the text.
The questions your students will answer include:
- What makes up a voltaic battery?
- Why do lemons and limes have the ability to “run” or power an object?
- What activates an electrical current, and why is that important?
After reading the passage and answering the questions, you can invite your students to share their responses and have a classroom discussion about electrical currents.
How Can I Get the Free Printable?
What are your favorite science activities? Let me know in the Комментарии и мнения владельцев! I am always looking for new science experiments that my students will love.
If you want more resources and even freebies for science, click here to check out my other posts, such as Apple oxidation, erosion with grass, dissolving Peeps, gingerbread cookies and candy hearts, creating avalanches and frost, states of matter with chocolate, experiments with growing plants and flowers (including a seed race), and much more.
How to make a Penny Battery
In a previous article, I showed you how to make a battery out of a potato. What we learned is that the potato doesn’t make the electricity, but rather a chemical reaction between the copper and zinc do, and all they need is an electrolyte between them. In this tutorial we’re going to learn how to make a penny battery which works on the same concept, just without the potatoes!
Watch the Penny Battery Video
Check out this handy video we put together on making a battery out of pennies. It’s super simple and fun science experiment!
How to Make a Penny Battery
To make a battery out of pennies is super simple, but the science behind it might not be all that easy to understand at first. It might help to read our articles on voltage and current to get a good idea of how electricity works. In a nutshell, batteries are nothing but devices that hold potential electrical energy that can be created via a chemical reaction! We’ll put those principles to use in our penny battery!
Parts List for this Project
Here’s a quick parts list for this project to help you get started:
A multimeter isn’t necessary for this project, but it makes it more fun. We also have a fantastic multimeter tutorial if you need some help!
Let’s Make a Battery out of Pennies!
Step one is to pour some vinegar into a small glass or similar small container. This vinegar will be the electrolyte in our project. Vinegar is considered to be a weak acid. There are other acids which are better electrolytes, but not safe for kids and hobbyists to experiment with at home.
Take your sections of cardboard and use the washers to trace out circles. You’re going to need several of them, so trace it a few times and then cut them out with some scissors or a razor knife.
Put the cardboard circles into your glass of vinegar and stir them up a bit. These need to soak for at least two minutes. I’d suggest you stir them every 30 seconds or so for the best results.
Make a small strip from aluminum foil and lay it out on a paper towel. Connect one end of it to the ground lead on your multimeter. This is technically optional, but will make it easier to check the voltage of the penny battery. At the other end of the aluminum strip, set a zinc washer onto it.
Blot dry one of the cardboard circles using the paper towel, but don’t dry it out. And then place it on top of the zinc washer. Finally, add a penny on too of the cardboard. If you touch your multimeter to the penny you should get just under 1 volt. In my case I got 0.8 volts. That’s really incredible when you think about it!
To make it even more powerful, lets add two more cells consisting of a zinc washer, cardboard circle and penny stacked on top. If you measure it again you should get somewhere between 3 and 4 volts. In my case I get 3.4V! I’m super impressed!
To keep it all together, I wrapped my penny battery with a couple of strips of electrical tape. Then I gently inserted a blue LED from the potato video and it lights right up!
And that’s how you make a potato battery, without the potato!
Amazingly, 24 hours later, its still going strong and I can’t help but wonder, “How long will this thing last?” (Update: It lasted about 72.5 hours!)
Details on How Penny Batteries Work
Now that you’ve completed the project, let’s talk just a bit more about how the penny battery works and its all because of the chemical composition of the metals.
Penny batteries work by converting chemical energy of the two different metals interacting with an electrolyte. In the case of the penny battery that electrolyte is the vinegar. The cardboard simply acts as a substrate that holds the vinegar in place, but has no effect on energy creation.
The copper in the penny, and the zinc in the washer’s surfaces serves as the electrodes. An electric current is created when the wire connects both metal surfaces and completes the circuit. This could be your LED or it could be the connection of your multimeter’s test probes.
Lemon Battery Science Experiment
We love building circuits around here. From our very first Circuit Bugs creation to Potato Batteries, we have had a lot of fun over the years experimenting with low voltage experiments and electricity in our elementary science lessons. With summer here, that means lemons and lemonade. It also means it was time for us to create the favourite lemon battery science experiment.
How to Build a Lemon Battery
What you will discover in this article!
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We often talk around here about the energy in nature and in everything around us. When we can power a light bulb with that energy it suddenly makes it very real for my kids. That energy isn’t just some crazy weird thing that I babble on about, it is this very real power that is showing itself right in front of them.
Normally our circuits are powered by batteries, but one day I convinced the kids we could power a light bulb with nothing but a potato. You should have seen the looks on their faces! Serious side eye was thrown my way.
Then, once they stopped straining their eyeballs, we built a potato battery and it worked! These kinds of science experiments for kids really stick with them. Why? Because it makes things real that they can’t otherwise see. Like the energy in our food.
Plus, when a child starts a science experiment with serious doubts, yet still achieves success, it powers up their curiosity!
So when we went grocery shopping and there was a huge pile of fresh, juicy looking lemons on display the kids asked to buy some for lemonade, but I knew we had another science experiment in our future.
Note: These food based battery experiments produce low voltage and are safe for older, responsible children to do under adult supervision.
How to Build a Lemon Battery Video
Watch as I go through the whole experiment step by step in our video tutorial. If you can’t see the video, please turn off your adblockers as they also block our video feed. Alternatively, you can also find this video on the STEAM Powered Family YouTube Channel.
Lemon Battery Materials
Lemons! You need at least 4 to create enough energy, but why not grab extras and experiment?Copper platesZinc platesAlligator clips with wires (2 per cell, so minimum 8 if you are creating a 4 cell battery)LED light bulbsMultimeterKnife
Copper and Zinc plates are invaluable in our science experiments, but if you don’t have them, you can use copper pennies (the older the better) and zinc plated (aka galvanized) nails. Copper wire can also be used, and a search of your local hardware store is likely to produce other copper and zinc items you could test in your experiment.
Looking for a quick out of the box solution?
MEL Science does Lemon Batteries as one of their monthly experiments. We LOVE MEL Science, it is one of our favourite educational subscription boxes. See all the amazing things your young scientist can do with MEL Science.
Lemon Battery Science Experiment
The first step is to roll the lemons. Just like you would if you were about to eat or juice them. This releases the juices inside and we want our lemons as juicy as possible.
Start with one lemon and make a small cut through the peel on either end. It is very important that you place these far enough apart that the electrodes don’t touch.
Insert a copper plate on one side and a zinc plate on the other side.
Now using your multimeter test your energy levels.
Now it is time to start adding more cells (lemons) to our battery.
Repeat the above steps on a second lemon. Once you are finished use an alligator clip to connect the zinc plate on the first lemon to the copper plate on the second lemon.
Test your energy level with 2 cells (you will test by touching the copper plate on the first lemon and zinc on the second). Remember you are completing the circuit.
Now repeat the steps to add a third and fourth cell.
At 4 cells we are now registering more energy than 2 AA batteries, which we tested in our Potato Cell experiment.
Now it is time to hook up our light bulb!
The goal of making a lemon battery is to turn chemical energy into electrical energy, creating enough electricity to power a small LED light. You can also use limes, oranges, potatoes, pumpkins/squash, or other acidic foods.
How A Lemon Battery Works
How does a lemon battery work? The science behind how food can power a light bulb is really fascinating. Food has energy. With a lemon battery we are capturing that energy and using it to light up a LED. To do this we need electrodes to capture the energy from our electrolyte.
The zinc and copper plates are called electrodes, and the lemon juice is our electrolyte.
All batteries have a “” (known as the cAll batteries have a “” (known as the cathode) and a “-” (known as the anode) terminal. In our lemon battery, the copper plate is our positive cathode and the zinc plate the negative anode. The zinc metal (our negative anode) reacts with the acidic lemon juice (mostly from citric acid) to produce zinc ions (Zn2) and electrons (2 e-).
Electric current is created by the flow of atomic particles called electrons. Conductors are materials that allow electrons (and the electrical current) to flow through them. Electrons flow from the negative to the positive terminal.
So in our experiment electrons are flowing from our zinc plate, through the lemon juice to the copper plate. From there it goes into our alligator clip, along the wire, into the zinc plate on the next lemon, where it picks up more energy as it travels through that cell. It continues on, building energy with each additional cell we add. Until finally we have enough voltage to power a light bulb.
Volts (or voltage) is a measurement of the force moving the electrons through our lemon battery. The higher the voltage the more power the battery has, but higher voltage also means greater danger. Always remember to be careful and safe around electricity. Thankfully our lemon battery is very low voltage.
Troubleshooting
There are a number of things that can cause issues with your Lemon Battery.
First, make sure none of your electrodes are touching anything other that lemon and alligator clips. Also, ensure your alligator clips are placed near the peel of the lemon.
Did you roll your lemons? You want them juicy for this experiment to work.
Did you mix up any of your connections? Remember you always want to link “” to “-“. On an standard LED light bulb the longer pin is the positive connection.
Does your LED bulb work? Test it on a coin battery to ensure your bulb works. It may be you have a faulty bulb.
Another area that can cause problems is the quality of your copper and zinc. You want your copper and zinc to be as pure as possible so it can conduct the electrons without any interference. This is one of the reasons I suggest investing in proper plates, so you know the quality of your materials when conducting experiments.
Finally, these food based batteries dimly light up the LED. If you hook your LED up to a regular battery, it will glow much brighter.
Fruit Battery Experiments
So now we have made both a lemon battery and a potato battery, which one is better? Both were able to light up our LED light bulbs, so in that sense they are both successful. However, the potato battery was definitely a lot more work. So if you are looking for a quicker experiment, the lemon battery is faster and easier. However, both have significant opportunities for learning and would make great science fair projects. Why not do both yourself and see what you think?
And in the fall, don’t forget to make a battery with pumpkins and squash! The concept is similar to Lemon Batteries but with a Autumn/Halloween theme.
Want to dig in more? Try this experiment with other citrus fruit such as oranges or lime or grapefruit. You can also combine a variety of fruits to see which combination makes the best fruit battery.
How to Reuse Lemon Battery Cells
This lemon science project is a ton of fun but once you are done, what can you do with the lemons? It seems like such a waste to throw them out. We have two really cool projects to do next with your lemons!
Check out the gorgeous lemon volcano we created here after building our lemon batteries!
Another great project with these lemons is to make Lemon Oobleck for a fun, summery sensory project.
Electricity Experiments
Welcome to STEAM Powered Family! Here we are constantly looking for ways to foster curiosity and a love of learning in our children, regardless of ability or history. With a FOCUS on STEM and STEAM (Science, Technology, Engineering, Arts and Math), and positive children’s mental health practices, our goal is to foster resilient, healthy minds. Read …