Best Rv batteries

Lithium batteries are out of my price range so I cannot comment. I wanted the "best" in terms of capacity, durability and no maintenance. I went with AGM and found a size where 2 batteries will barely fit into my battery compartment (after I removed the sliding tray). Maintenance is now out of the question. Since I was a full timer, I went with what my dealer recommended as the best quality and most durable battery. Lifeline, specifically the 30HT size at 150 AHs each. I had a cheap converter/charging that was fixed at 13.3 volts. I also had solar with a fixed 13.6 v charger. I probably shortened the life of my batteries since they were often undercharged and when in storage the float at 13.6v was too high. I got 7 years of use out of them including 2 years of full time use. I ran an electric refrigerator and my wife's cpap, along with the other uses such as computers, lighting and the furnace. I might have tried to extend their life by trying reconditioning but replaced them instead. I think that is about as much as you can expect to get from conventional batteries and at about $900 that should be the case.