I use solar panels the 30watt 20x20" size on my lockup , and a 12x8" on my shed for led spots and run an inverter in the shed for mini lathe drill grindstone etc . I did use old car batteries , But Got lucky with the batteries as the panels on the house roof also has a battery storage box , 6x truck size batteries , But the lead acid were not compatible with the electronics so the install company changed them to GEL , so I asked what happens to the lead batts only 4 months old , said basically scrap so obviously asked if I could have a couple said have the lot , and they loved recycling . So back to it for the larger shall we say proper panels on the garage I do use a controller although most have built in diodes to stop self discharge , so on the shed i did but now dont and no change in performance .
But for a vehicle I think the Amazon ones are more pack-able and easier to store than a standard panel + a controller which would be a bit cumbersome to cart around , Great for caravans and garage type use . I have a spare new big 30+ watt panel , need to check could be higher , But will get ie the type from Amazon for the van .
