one deep cyle battery or 2?

[astrotrailer]

I started with a 12 volt 130 amp-hour marine battery feed by a PWM controller attached to pair of 80 watts of solar panels wired in parallel. After 2 years of use and increasing power needs, 12 volt Engel, more laptops for astro-imaging, I upgraded. I now have three 80 watt solar panels wired in series feeding the SunSaver MPPT solar controller attached to a pair of 6 volt Trojan 220 amp-hour deep cycle batteries. I get about 15 amps of charging from the MPPT solar controller into the battery bank under full sun. I run a personal evaporative cooler pulling 2 amps, the Engel freezer pulling another 2 and still have plenty of power to recharge my batteries in the day time. At night I am running a couple of laptops, two astronomy mounts, 4 cameras plus the Engel is still going but not cycling on as much because it is cooler at night.

Most campers aren't going to need as much power as I use for astronomy imaging. I like having the extra capacity because I also camp in the winter and run a 2 amp RV propane furnace and my solar output is less in January. I add distilled water every couple of months to my batteries. The solar setup still gets plenty of sun where my 5x8 is parked at my house so the batteries are always topped up and ready to use.

[LandCommander]

Series connected batteries can have issues just the same with parallel. What do you think will happen if one of your cells fail and only charges to half voltage? The other cells will pick up the slack and overcharge to compensate. Just saying that in a perfect world every cell would get its own isolated charge.