Build a solar powered charger
Build a simple solar charger with a small solar panel, rechargeable battery, and USB module, learning about renewable energy and circuits.
About this activity
Build a simple solar charger with a small solar panel, rechargeable battery, and USB module, learning about renewable energy and circuits.
What you need
Step by step
- 1
Step 1
Lay out all materials on a clean table so you can see everything clearly.
- 2
Step 2
Have an adult help you identify the positive wire color red and the negative wire color black on the solar panel and on the controller.
- 3
Step 3
Attach the solar panel wires to the controller input terminals using the alligator clips matching red to the controller + and black to the controller -.
- 4
Step 4
Plug the rechargeable battery connector into the controller battery port matching the battery connector orientation.
- 5
Step 5
Move the solar panel into bright sunlight so the controller can start receiving power.
- 6
Step 6
Watch the controller charging LED to confirm the controller shows it is charging the battery.
- 7
Step 7
Plug the USB cable into the controller USB output port so you can power a device later.
- 8
Step 8
Secure any loose wires with small pieces of electrical tape so nothing pulls loose.
- 9
Step 9
Place the controller and battery neatly inside the small plastic box and close the lid to protect the parts.
- 10
Step 10
Label the box with the marker and adhesive label with a name like Solar Charger and today’s date.
- 11
Step 11
Leave the solar panel in the sun for at least one hour to charge the battery inside the controller.
- 12
Step 12
Test your charger by plugging a small USB device into the USB cable and then share your finished creation on DIY.org
Fun facts
How do I build a simple solar-powered USB charger with a small panel, battery, and USB module?
Start by connecting a small 5V solar panel to a solar charge controller or a TP4056 module designed for solar input, then connect a rechargeable Li‑ion battery to the controller, ensuring a protection circuit is present. Add a USB boost or use a module that outputs 5V USB. Use a blocking diode to prevent backflow at night, secure connections with solder or screw terminals, mount components in an enclosure, and test in full sun with a multimeter. Always supervise and follow battery safety.
What materials and parts do I need to build a kid-friendly solar charger?
Materials: a small 5V solar panel (1–6W), a rechargeable battery (protected 18650 Li‑ion 3.7V or a 3.7V LiPo), a solar charge controller or TP4056 with solar input and protection, a USB boost converter to 5V (if needed), diode, wires, switch, enclosure, and mounting hardware. Tools: soldering iron, wire strippers, hot glue, multimeter, and safety goggles. Optional: LEDs, indicator, and small voltmeter module.
What ages is this solar charger activity suitable for?
Suitable ages: With adult supervision, children aged 8–12 can participate in wiring, assembling parts, and learning concepts. Ages 12+ can handle soldering and more independent construction if they understand battery safety. For children under 8, limit to hands-on learning like mounting parts, labeling wires, and testing solar power while adults handle electrical connections. Always supervise all ages around batteries, soldering irons, and tools.
What are the benefits, safety tips, and simple variations for this solar charger project?
Benefits include hands-on learning about renewable energy, basic circuitry, problem-solving, and environmental awareness. Safety tips: always use a protected battery, include a charge controller, never short cells, wear eye protection while soldering, and supervise children. Variation: build a portable USB-only pack, add LED charge indicators, or use a small solar-powered powerbank kit to simplify components. These changes let families scale complexity to skill level and safety needs.
Watch & Learn
Need help?
What can we use instead of hard-to-find alligator clips or the small plastic box?
If you can't find alligator clips, strip and loop the solar panel wires under the controller's input screw terminals or use a small terminal block, and if you don't have the small plastic box use a clean Tupperware container or pencil case to hold the controller and battery.
The controller's charging LED won't turn on — what should we check?
If the charging LED doesn't light, verify red is connected to the controller + and black to -, make sure the rechargeable battery connector is fully plugged in, secure any loose alligator clips or wires with electrical tape, and move the solar panel into brighter sunlight.
How can we adapt the activity for younger kids or make it more challenging for older kids?
For younger children have an adult handle step 2–4 (identifying wires and attaching clips) while the child lays out materials, closes the box, and watches the LED, and for older kids add soldered connections, a larger battery, or design an adjustable panel mount before labeling and testing the USB output.
What are simple ways to extend or personalize the solar charger project?
Enhance the charger by adding an inline switch on the controller's USB output, installing a blocking diode at the panel input, upgrading to a larger solar panel for faster charging, mounting the panel on a tilt stand for better sunlight during step 5, and decorating the plastic box with stickers and a personalized label.