batteries

You can use the AGM design batteries without venting them .
Over time I have converted to AGM batteries for the cars , TT , and boat .
The reasons why are given in detail in wikipedia .
The cheapest AGM design that I have found are Exide EDGE AGM batteries from BiMart for $ 140 each .
They have a marine / rv style and about 10 auto fitments .
The EDGE is 100 % replacement guarantee for 4 years in automotive styles .
Group 78 is the side post GM for my duramax but I use that Grp 78 in my boat also .
It takes a 5 /16 standard bolt and allows me to connect the additional Marine gadgets to the 78 side posts .

Kind of a side note -- my battery box will only hold one 12V class 27 battery. Can I build/buy/install a new vented battery box somehow? Perhaps in the basement up front? Or can I use AGM batteries and just not vent them? Thank You!

Our last two RV's have been delived with two 12 volt batteries already installed. We now use a Montana 3750FL with batteries connected in Parallel as it came from the factory

suedonlem wrote:
Can you connect 2 twelve volt batteries in a fifth wheel and if so how?

As already posted positive to positive and neg. to neg.


To double the amps over 12 volt batteries each 6 volt battery would need to have double the amps as each 12 volt battery.

My experience has been that the golf cart battery will last longer than any 12 volt battery I have used.

One thing that is very important to consider when connecting two batteries together is they MUST be as close as possible date wise! The optimum would be to have 2 batteries with consecutive serial numbers. The reason is thw weaker of the two will bring down the stronger one, never the other way around! If you currently have an existing 12 volt that is a couple of years old, adding a new 12 volt in series will be a waste of your money, as the new one will fail prematurely! If you need to add batteries for dry camping or adding capacity, please buy two new ones and check both manufacture date as well as the serial numbers and get them as close as possible! Good luck!

KD4UPL wrote:
positives together, negatives together. Connect as many as you like.
However, there are better ways to get a big battery bank if you need more than 2 12v batteries. Really, even with 2 12v batteries 2 6v in series would be a better choice.

x3. I had 2 12v batteries and, when they needed replacing, I went with 2 6v golf cart batteries from Sam's Club. < $200, including tax, for double the amp/hrs. I figure that, with 80-100 watts of solar, I'm self-contained, power-wise. I only have 45 watts of solar, so I'm good for 4-5 days, without too much conservation efforts. I figure another 24-48 hours if I get all my 12v bulbs changed to LEDs.

Lyle

KD4UPL wrote:
positives together, negatives together. Connect as many as you like.
However, there are better ways to get a big battery bank if you need more than 2 12v batteries. Really, even with 2 12v batteries 2 6v in series would be a better choice.

Plus one on this! Two 6v batteries will definitely give you more capacity than two 12v. If I was going to invest in 2 batteries, it would definitely be the best 6v that money could buy. There is a reason that golf carts use multiple 6v batteries not 12v and it is not because all those 6v batteries are cheaper.

positives together, negatives together. Connect as many as you like.
However, there are better ways to get a big battery bank if you need more than 2 12v batteries. Really, even with 2 12v batteries 2 6v in series would be a better choice.

gbopp wrote:
The 12 Volt Side of Life.

Interesting and informative.

That link/website is a classic... everything I ever wanted to know about connecting batteries. Relied on it every time I thought batteries

http://rvroadtrip.us/library/12v_system.php

Hello,

A nice article on 12v systems for reference. It also has a diagram to show how to connect the 2 batteries together.

Have fun!