Battery Power Unit Study and Meeting Plan

By Kerry Cordy
December 20, 2025

Batteries are everywhere—from the toy box to the toolbox, and even in the devices we use every day without thinking twice. This unit study to learn about Battery Power introduces kids to how batteries work, why they matter, and how to use them safely and responsibly. Along the way, they’ll explore basic electricity, the science behind circuits, and the evolution of battery technology. It’s a hands-on way to bring science, engineering, and environmental awareness to life. This topic also ties in well with the Electricity, Renewable Energy, and Robotics badges.

What Is a Battery?

Batteries are small power sources that store chemical energy and turn it into electrical energy. That electricity flows through wires and powers things like flashlights, toys, remotes, and phones. Most batteries have two ends; a positive (+) and a negative (–) terminal. Electricity flows from one end to the other, creating a current that powers devices.

There are many kinds of batteries, from tiny button cells to large car batteries, but they all work using the same basic principle: a chemical reaction inside the battery causes electrons to flow.

To Do:
Go on a battery scavenger hunt at home. Find a minimum of five objects that use batteries. Open them (with an adult’s help, if needed) to look at the size and placement of the batteries. Record the device, battery size, and whether it’s rechargeable or not.

Click to Download Scavenger Hunt Form

Fulfills Preschool requirement #1

Battery Safety

Batteries can be dangerous if not handled properly. Small button batteries can be swallowed and cause injury. Leaking batteries can cause burns. Overcharging a rechargeable battery or using the wrong size can even cause fires. It’s important to follow basic rules:

Never mix old and new batteries
Always use the correct size and type of battery for your device
Put batteries in the right way (+ and –)
Don’t store loose batteries in a pocket or drawer
Do not crush, puncture or damage batteries
Always charge batteries on a hard flat surface
Do not leave devices plugged in after fully charged
Do not charge batteries at temperatures below 32 degree or over 105degrees
Recycle batteries, do not throw in your trash can

To Do: Create a poster or checklist of battery safety rules to hang near your battery storage area. Include images or drawings to make it easy for younger children to understand.

To Do: Battery Safety Sorting Race

Objective: Quickly sort safe vs. unsafe battery behaviors.

Supplies:

Two baskets or boxes labeled “SAFE” and “UNSAFE” for each team
A stack of cards or slips of paper with different battery-related scenarios (see examples below). One set for each team

Examples of Card Scenarios:

“Store batteries away from heat” → SAFE
“Put batteries in your mouth” → UNSAFE
“Use the right size battery for your device” → SAFE
“Throw batteries in the trash” → UNSAFE
“Ask an adult before changing batteries” → SAFE
“Mix old and new batteries together” → UNSAFE

Instructions:

Divide kids into two or more teams and play relay race style. The first child runs to the table with their cards and baskets, takes the first card off the stack, reads it and places it in either the safe or unsafe basket. They then run back, tag the next person and repeat. First team to get all theirs cards in their baskets calls a halt to the race.

Pull out each card from the basket and read it aloud. If it was placed in the correct basket the team gets one point. If it was placed in the wrong basket, the team loses one point. The team with the most points wins.

Just because a team finishes first and gets all their cards in their baskets, doesn’t automatically mean they will win. They just have the advantage of having more cards. If several cards are in the wrong basket however, that team may still lose to a slower team who was more accurate in their sorting. Always start scoring with the slowest team and end with the fastest.

Fulfills Preschool requirement #2

Polarity: Why Direction Matters

Every battery-powered device has a correct way to insert batteries. If you put them in backward, the device won’t work. That’s because electricity flows from the negative end to the positive end through a circuit. If you reverse the direction, the circuit breaks and no power flows.

To Do:
With a flashlight or small toy, practice inserting batteries the right way. Observe what happens if they are put in backward. Then fix the orientation and see the difference.

To Do: Make a Polarity Tester

Supplies:

Small LED bulb or LED diode (from a craft store or science kit)
2 wires with alligator clips or stripped ends
AA battery and holder (or just hold the battery manually)

Instructions:

Connect the LED to each side of the battery using wires or clip leads.
Reverse the connections. What happens?
Note which direction makes the light turn on.
Mark the direction that lights up the LED to show the correct flow from positive to negative.

To Discuss:
LEDs only light up in one direction, just like electricity flows one way through a circuit. What does that tell you about the battery’s polarity?

Fulfills Level 1 requirement #2

Vocabulary of Battery Power

Understanding how batteries work means learning some new words:

Circuit – A circuit is a complete path that electricity flows through to power something like a light or toy.
Current – Current is the flow of electricity through a circuit, like water running through a hose.
Voltage – Voltage is the force that pushes electricity through a circuit to make it move.
Electrolyte – An electrolyte is the chemical inside a battery that helps create electricity.
Terminal – Terminals are the two ends of a battery (positive and negative) where electricity flows in and out.
Conductor – A material that electricity can flow through easily, like metal.
Insulator – A material that blocks electricity from flowing, like rubber or plastic.
Polarity – Knowing which end of the battery is positive (+) and which is negative (–).
Short Circuit – A mistake in the wiring that causes electricity to go the wrong way and possibly overheat.
Energy Transfer – When energy moves from one thing (like a battery) to another (like a toy or light).

To Do: Play the Battery Word Circuit Game
Supplies:

Vocabulary word cards written in red
Definition cards written in blue
image of a light bulb
image of a battery
String or painter’s tape to make a “circuit path” on the floor
Stickers
Optional: Flashlight or battery-powered toy as a prize for finishing the circuit

Setup & Instructions:

Create a path on the floor shaped like a circuit (large circle) using string or painters tape.
Place the image of the light bulb on one side of the circuit with vocabulary words placed on either side.
On the opposite side, place the image of the battery and matching definitions.
Kids must pick a word card, walk the “circuit,” and stop to match it with the correct definition.
If they match correctly, they complete the “circuit” and earn a “power boost” (sticker).
Incorrect matches “short circuit” and must go back to try again.
Continue around the circuit until all vocabulary words are correctly matched.

Variations:
Use pictures instead of definitions for younger kids, or make it a timed relay race in teams.
Fulfills Level 2 requirement #2

Who Invented the Battery?

The first real battery was invented by Alessandro Volta in 1800. It was called the voltaic pile and was made from layers of metal and cloth soaked in saltwater. Since then, battery technology has evolved—from the big lead-acid car batteries of the early 1900s to today’s tiny rechargeable lithium-ion cells.

To Do:
Create a timeline showing how batteries have changed over time. Include at least 5 milestones such as the voltaic pile, first dry cell, rechargeable batteries, lithium-ion invention, and modern electric car batteries.

For fun and unique timeline ideas visit our blog: 9 Fun Timeline Activities to Make History Come Alive

Fulfills Level 3 requirement #2

Different Types of Batteries

There are many types of batteries, each with its own pros and cons:

Alkaline – Cheap and long-lasting, but not rechargeable.
Lithium-ion – Rechargeable, powerful, and common in phones and laptops.
Lead-acid – Used in cars; heavy but good for high power.
NiMH – Rechargeable, used in cameras and toys.

To Do:
Make a comparison chart of at least four battery types. Include what they’re used for, if they’re rechargeable, and pros and cons for each. A great resource for battery types can be found on the Ecoflow website at: https://www.ecoflow.com/za/blog/different-types-of-batteries

Fulfills Level 4 requirement #2

Make a Battery at Home

Building a lemon battery is a fun and hands-on way to explore how chemical energy can be turned into electrical energy. Using simple materials like a lemon, a nail, and a penny, kids can create a working circuit and see how acids help produce electricity. This classic experiment is perfect for learning how batteries work and ties directly into the Battery Power badge. It’s a great way to spark curiosity about science, energy, and real-world technology—all with a piece of fruit.

To Do: Make a Lemon Battery

Supplies Needed:

1 large lemon (or more if you want to experiment)
1 zinc-coated nail (galvanized nails work best)
1 copper coin (penny – pre 1982 works best) or piece of copper wire
1 small LED light (1.5–2 volts) or digital voltmeter/multimeter
2 insulated alligator clip wires (or regular wires with stripped ends)
Small knife or pencil to make pilot holes

Safety Note:

While this experiment is safe, always wash hands after handling zinc-coated nails, and don’t eat the lemon afterward.

Instructions:

1. Prepare the Lemon

Roll the lemon on a hard surface with gentle pressure to soften it inside. This helps release more juice and improves conductivity.
Use a pencil or pen to poke two small holes about 1–2 inches apart.

2. Insert the Electrodes

Insert the zinc nail into one hole. This acts as the negative electrode (anode).
Insert the copper penny or wire into the other hole. This is the positive electrode (cathode).
Make sure the two metal pieces do not touch inside the lemon.

3. Attach the Wires

Use the first alligator clip to connect the zinc nail to the negative (-) lead of the LED or voltmeter.
Use the second clip to connect the copper to the positive (+) lead.
If using a voltmeter, you should see a reading around 0.7–1 volts.
If using an LED, it may glow faintly—or not at all with just one lemon. Don’t worry! Keep experimenting by adding more lemons.

Want More Power?

To increase the voltage, connect 2–4 lemons together in a series:

Insert a zinc nail and a copper wire into each lemon.
Use wires to connect zinc in Lemon 1 to copper in Lemon 2, and so on.
Attach your LED or voltmeter to the first copper and last zinc in the series.

You should get enough voltage (1.5–2V) to light a small LED with 2–3 lemons! Remember that an LED light must have the correct positive and negative leads attached. If it still won’t light with several lemons, you may have the leads backward.

What’s Happening?

The zinc reacts with the acidic lemon juice, releasing electrons.
The copper collects those electrons, creating an electric current.
The lemon juice acts as the electrolyte, completing the circuit.

This setup mimics a basic battery: two electrodes and one electrolyte = chemical energy turned into electrical energy.

Fulfills optional requirement #4

Extension Ideas:

Try other fruits or vegetables like potatoes, limes, or oranges. Which one produces the most voltage?
Create a chart comparing the voltage of different citrus fruits.
Draw and label a diagram showing the flow of electricity in your lemon battery.

Battery Recycling & Environmental Impact

Batteries don’t last forever, and throwing them in the trash can harm the environment. They contain metals that can leak into the soil or water. Some types can even explode if punctured or overheated. Recycling helps recover materials and prevent pollution.

To Do:
Start a battery recycling bin at home, school, or your local library. Research where to drop off used batteries in your community. You can find local drop off locations by entering your zip code at: https://www.call2recycle.org/ Make a small poster explaining why recycling batteries matters.
Fulfills optional requirement #6

Build a Battery Tracker

From the moment we wake up, we’re using battery-powered devices: phones, toothbrushes, remotes, toys, flashlights, clocks, and more. Tracking how much we use them helps us understand how important batteries are in daily life.

To Do:
Track all the battery-powered items you use in one day. List the item, battery type, and how long you used it. Make a bar chart or pie graph to show which items use the most battery time.
Fulfills optional requirement #7

Other Ideas to Explore

Interview someone who works with batteries daily (e.g., mechanic, electrician, solar tech).
Visit a battery store and make a photo journal of the different types you find.
Design your own invention powered by batteries—draw it and describe what it does.
Watch a documentary or video about how batteries are made.