Let’s Build 5V Solar Charger



I am taking an online summer class at University of Minnesota regarding renewable energy. I took a project of building a solar charger to charge my bike LED light. This will be a fun small project. The items used for this project are Adafruit phone charger kit and 6V 1W solar panel.
     


       

The above kit is a basic step-up converter circuit PCB that converts a variable input voltage to 5V output. It is meant to use two 1.5V battery cells. However, for this project, I will use a solar panel instead. The solar panel is advertised to output 6V. According to the LTC1302 datasheet of the boost converter used in this kit, the input voltage has a range from 2V to 8V. Therefore, this solar panel rated for 6V output should be appropriate for this build.



I soldered all the parts according to the instruction here: https://learn.adafruit.com/minty-boost/solder-it. This is an easy task to people who have prior experience with soldering. Next week, I will demonstrate the use of the light charger when I install this on my bike. Since bike light is only used when dark, the bike light should be already charged when I ride during the day. This is a great application of the solar panel. Hopefully, I will never have to charge my bike light again!

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