I looked through the forum but didn’t find an answer. I would like to charge a couple of 12v deep cycle batteries from SP120s but would like input on safest way to do this (using tender but looking for option during power outage), what would I need to .make this set up work? TIA
A charger controller connected to the output leads from the solar panels. Here is a link to “Renogy” brand charge controllers. The charge controller is basically a battery charger that will charge your deep cycle batteries and then will stop charging automatically when they are full. The charge controller just needs to be sized to your maximum amp output of the panels. I would recommend a 20 amp model. Solar Charge Controllers & Battery Chargers for Sale| Renogy
Here is a link to a renogy panel that comes with a charge controller (this would be the same basic set up you would be using) to see as an example. Go to the pics section and the last pic shows the panel with the charge controller connected and the deep cycle batteries attached how you would be doing it. The charge controller could be wired with MC4 connection input leads and would simply snap onto your existing solar panel MC4 connections. The output cable of the charge controller would then be connected to your deep cycle batteries. 100 Watt 12 Volt Portable Solar Suitcase w/o Voyager| Renogy Solar
I am not recommending one brand or another of charge controllers but simply using the links as examples. I have used the renogy panels with the shown charge controller successfully myself though.
Thx Scott, I appreciate your input.