Joining 12v Solar Panels

Norman_Castle

I've got two 12v car solar panels, a 2.5 watt and a 1.5 watt. Both work but I'd like to connect them together, can I just join the positive and negative output cables, + to +, - to - then feed into the lighter socket without damaging the panels or car?

Heedtheadvice

Depends upon the panel types and charactetistics!

Assuming they are the same panel types and close charactetistics then look at the link below for parallel connection. You can probably ignore the voltage difference output in the link as yours are the same nominal voltage. The panels might have protection diodes in them too but that will only make a minor difference - if not you should add a low voltage drop one such as a shottky type to reduce the risk of battery discharge. They are so small there will be no significant issue then leaving them connected as with a large car battery there will be little risk of overcharge.

Solar Panels in Parallel with Different Voltages and Currents in https://www.alternative-energy-tutorials.com/energy-articles/connecting-solar-panels-together.html