Technically, the solar panel can be directly connected to the battery, and for small load set-ups, this is usually not a problem. A controller can be a part of the panel itself, but you'll usually see it as a standalone gadget that both your panel and your batteries connect to during the set-up process. See also: What A. If you're setting up an off-grid power system for your 4WD, caravan, camper or remote setup, you've probably come across the terms regulated and unregulated solar panels. They sound technical, but the difference is actually quite simple – and choosing the right one can make a big impact on how. In this post I have explained how to construct a simple solar panel regulator controller circuit at home for charging small batteries such as 12V 7AH battery using small solar panel We all know pretty well about solar panels and their functions. But remember this: you will need a solar charge controller to prevent overcharging the batteries.