Two(2) 6volt Batteries

[JMG]

Why are 2 six volt batteries better?
jmg

[bigmurf]

Give this a look.

http://www.macandchris.com/RVBatteries.htm

BTW: Here is a neat little item that helps the problem of WET batteries losing fluid.
http://discoverpower.com/shop/item.asp?PID=233

[8.1al]

We have used these caps on our Trojan T-105's and they work well
https://ssl4.westserver.net/rvsolare....htm#Batteries

[Waynem]

A search will result in a whole bunch of answers.

Here Is One

[OntMont]

If the quality of the batteries is equivalent, there is no electrical difference. The advantage, (to me anyway) is that good deep cycle batteries are heavy because they have thick lead plates. A Trojan T105 6v battery weighs about 65 lbs. That is just about as much one person can handle to get it into the awkward position most RV batteries are in. It is just easier to handle two 6 volt batteries than one 12 volt battery of equivalent quality and capacity. Golf cart batteries, such as the Trojan T-105, are mass produced and readily available at modest prices. (Be cautious of using "Marine" batteries, many of these are just automobile starting batteries with a fancy label. One tell-tale is that if the battery is rated in CCA (cold cranking amps) or MCA (marine cranking amps) it is a most probably a starting battery not a true deep cycle battery. A true Deep Cycle battery should be rated by its storage capacity in amp-hours.

[FLSTS03]

Another thought,if I remember correctly "back in my sailing days" my crusier buddies used two or three banks, one for engine/gen starting and one or two banks for house power and they would spend a couple thousand for batteries(usally 12's). I have one 12volt for house and generator,normally leave pos+ disconnected and so far had no problems(now I'm on shore power). I have thought about (2) 6's for house and keeping my 12 for genset. All that I have read about differences 6v12 was summed up by OntMont.

[bsmeaton]

Well I for one have never seen a 12-volt deep cycle battery with the equivalent quality of the 6-volt golf cart battery - so couldn't imagine what the weight would be. Either way, I tend to go with things that are somewhat easy to get on the road, and as OntMont says the 6-volt golf cart battery seems to be a regular staple product out there versus any kind of specialized 12-volt deep cycle of equivalent performance.

Short of doing the math again, I believe our (2) 6-volt batteries have more capacity that even 2 12-volt 72 series deep cycle batteries, not just one.

FLSTS03 - I believe your marine application also has merit in motorhomes - but I'm not seeing the real benefit for a trailer unless you are a serious boondocker and need the full benefit of your battery capacity range. Motorhomes, like your sheet boat buddies and even the stinkpots run the risk of being stranded if they run down the coach batteries below the level it takes to start the engine, so they typically have a dedicated chassis battery that only gets integrated into the system while underway and the engine running. On a trailer, you just go get the truck and plug in. Not sure I would waste the deckspace for a dedicated generator battery.

[skypilot]

A 'mild' warning about running the batteries down -- this past fall at a football tailgate we witnessed a fellow tailgater running his coach, 3 tvs with separate satelite receivers and numerous other electrical items (very large group of guys and gals enjoying the fall weather!!) --- in any case, during half-time went back to our 5er and saw that they were trying to jump start his truck -- he had drained not only the coach batteries but also his tow vehicles (had left everything plugged in). After the game when walking back they had a big Honda generator hooked up running everything !! (looked new!!!). Could have been a real problem had they been out in the boonies rather that in a town....