If you are building a small, low power project in a remote location, solar harvesting can be a great option. This solar charge solution for an 18650 battery makes this super easy to achieve in your project.
Whilst The Curious Electric Company originally designed this kit to power a remote weather station that sent back it’s data to a base station, it’s suitable to power any small device. We imagine it could be very useful, for example, for LoRa nodes and other remote sensing or data logging projects.
Using a Texas Instruments IC BQ24210 as the solar charge controller, this kit require a suitable 18650 battery and a small solar cell to get up and running. For the solar cell you can use any that will supply between 3.5V and 7V DC and Curious Electric state they get good results with a 5.5V 200mA panel. You can connect your project to the output which is protected with a 500mA resetting fuse. The PCB is supplied pre-populated with all the SMD parts fitted and you only have to solder in the battery holder and the screw clamp terminals which are larger through hole mount components.