That sounds like a plan. This is the best 12V LED I've found so far for close-to-120V lighting (and dimable) : https://www.ebay.com/itm/12V-70W-7000LM-LED-Panel-Strip-COB-Ceiling-Light-Tube-Lamp-220X120mm-White-Warm/293384558271a 12v large cell in the building that I will trickle charge via speaker wire or the like from my garage
I haven't looked inside, but the 16-LED 12V light is easily dimmable with a picaxe with PWM @ 1kHz and IRLZ44N or like MOSFET or mosfet module: https://www.ebay.com/itm/5-Pcs-kit-IRF520-MOSFET-Driver-Module-For-Arduino-ARM-Raspberry-Pi-33-24mm-New/353148084178I wonder if you have "looked into" the 16 LED unit to see what sort of regulator it has perhaps to make it dimable and or rewire a bit for 2x2 or 3x3 switchable LED configurations?
None that I have noticed, but I don't know exactly what I would notice it in. With one 12V module I was testing (I've tried a lot), I got flicker at a quite dim level, and it may have been mains-synchronized flicker, but I don't remember exactly which LED.have you noticed any RFI issues?