Make a DIY Solar Power Bank that folds!

Summary

In this tutorial, Max shows how to build a compact and efficient portable solar power bank with a custom-made folding solar panel. Using parts from DF Robot, including a lithium-ion battery holder, solar power management module, Beetle microcontroller, and LED lamp, Max walks through the step-by-step process of assembling the power bank. The video covers everything from wiring solar panels in parallel to programming the microcontroller for battery monitoring. The result is a practical, portable power bank capable of charging devices on the go. Max also compares the charging efficiency with different solar panels, showcasing the power bank’s versatility and efficiency.

Takeaways

• 😀 The video is about building an efficient solar power bank with folding solar panels, sponsored by DF Robot.
• 😀 The solar power bank is compact, portable, and made with various components from DF Robot, including a custom folding solar panel.
• 😀 The solar panel is made using small polycrystalline panels soldered together to create a more portable array, unlike the larger monocrystalline panel provided by DF Robot.
• 😀 When wiring the solar panels, it’s crucial to connect them in parallel to increase the output current, with a gap of at least six millimeters between each panel for folding.
• 😀 Electrical tape is used to cover the gaps and wires between the solar panels to ensure flexibility when folding the panels.
• 😀 A key part of the build is adding a battery capacity indicator and a push button to toggle the display on and off, using a DF Robot Beetle microcontroller.
• 😀 The power bank is wired with a 2-cell lithium ion battery holder configured in parallel to increase current output and power storage.
• 😀 The power bank is equipped with an LED lamp made of three 8mm LEDs wired in parallel, powered directly from the battery, and regulated by a current-limiting resistor.
• 😀 The power bank is assembled inside a custom container with appropriately sized holes for the components, using double-sided tape and glue to secure everything.
• 😀 The microcontroller is programmed using Arduino IDE to read the battery voltage and control the display, while the switch allows for charging via solar or USB.
• 😀 The solar power bank charges devices like smartphones effectively, with real-world testing showing it can charge a phone from 7% to 21% in around 10 minutes with the folding solar panel.

Q & A

What is the main focus of the tutorial in the video?

The main focus of the tutorial is to teach viewers how to build an efficient, portable solar power bank using folding solar panels. The tutorial covers assembling the power bank, integrating the solar panels, and programming the microcontroller to manage power flow.

Which components are required to build the solar power bank?

The required components include a dual lithium-ion battery holder, battery capacity indicator module, beetle microcontroller, green LED push button, 5V solar power management module, 6W monocrystalline solar panel, polycrystalline solar panels, duct tape, electrical tape, resistors, and various connectors.

Why did the creator choose to use polycrystalline panels for the folding solar panel?

The creator chose polycrystalline panels for the folding solar panel because they are less bulky and more portable compared to the monocrystalline panel, which was not integrated into the power bank but instead used for testing.

What is the process for wiring the solar panels together?

The process involves soldering the solar panels in parallel to increase the overall output current. The panels are then connected with output wires for a connector, and flaps made from duct tape are used to hold the panels together, allowing them to fold easily.

How does the power bank's battery capacity indicator work?

The battery capacity indicator works by using the beetle microcontroller to read the voltage of the battery. It is connected to a push button that toggles the display on and off, showing the battery's current charge level.

What is the role of the solar power management module in the project?

The solar power management module is responsible for managing the input power from the solar panel and charging the battery. It ensures the proper flow of electricity to the battery while protecting the system from overcharging or other electrical issues.

Why is it important to desolder parts of the solar power management module?

It is important to desolder certain parts of the solar power management module to make the board fit inside the power bank's enclosure. This step ensures that the module does not interfere with the compact design of the power bank.

How are the LED lights integrated into the power bank?

The LED lights are integrated into the power bank as a small lamp, wired to the battery with a current-limiting resistor. The LEDs are glued together, and the lamp is mounted on the side of the power bank to provide an additional feature.

What was the problem encountered with spray painting the duct tape on the solar panels?

The problem with spray painting the duct tape was that the paint easily peeled off, which made it a poor choice for securing the panels. The creator advises against using paint and instead suggests using electrical tape, which does not restrict the folding movement of the panels.

How long does it take to charge the power bank using the homemade solar panel and the monocrystalline panel?

The homemade polycrystalline solar panel takes approximately six hours to charge the power bank in direct sunlight, while the monocrystalline solar panel takes around four and a half hours. These times may vary depending on the intensity of sunlight and other factors.

What is the charging rate when using the solar power bank to charge a phone?

The power bank can charge a phone at a rate of about 0.7 amps with the semi-flexible solar panel and 0.57 amps with the homemade folding solar panel. This is comparable to charging from an outlet, with the charging rate depending on the phone's battery capacity.