Need a solar panel for a vex

im wondering if you could help me finding solar panel with at least 18Volt
I found one solar panel but It has two usb output But i need solar panel with two outputs , one 18V Output for vex rover and one 5V usb power to Raspberry pi. Is there any solar panel that has what i need?
This link below is the solar panel i found but it has 2 usb output unfortunately

Vex motors are designed to run off 7.2V so 18V is too much for them.

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You should scout around for teams that have unused 393 motors and use them for these solar projects. A gunk (good but not wanted) Cortex and kit will work fine. Putting at risk a $55 battery and a V5 brain seems a little wonky for a science fair project.


I would suggest, if you want to try solar power on a v5 system, that you go the route of making a solar powered battery charger for the v5 battery connected to the brain. We know that the v 5 battery can operate the brain while connected to the charger, so this will give you system stability. Investigate “three terminal regulators,” and connect your solar cell to a voltage regulator circuit that matches the output of the V5 charger. Connect to the output of this circuit to the v5 battery, and you should have a system that will work without risk of damage to the V5 system.


A simple linear(3 wire) regulator will waste a lot of energy and get very hot as it will simply ‘cut off’ the excess voltage and turn it into heat. A buck converter would be better as it would lower the voltage to the required 16V for battery charging without losing much energy.
Edit: or a boost converter is the solar panel is <16V


Yes, a buck converter would be better…last time I had to build a little DC-DC converter for a job, those didn’t exist (yes, I’m pretty old, and I only dabble in controls a little bit), and the 3-terminal regulator was the best thing since sliced bread.

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