How many amp hours do you have?

[Bryan]

Recently I have been discussing power issues in my RV on here and some of the posts I have read have left me wondering...


How big is your house battery bank?

My 'new' RV had just 1 x 85ah 12 volt battery.  I am currently upping that to 2 x 85ah and 1 x 80ah 12 batteries but I suspect that you may have a lot more.

Bryan

 

[Tom]

Our coach has 4 golf cart batteries; They're 6V, so they're connected in series pairs to provide 12V. Total = 440AH at 12V. It's not good to repeatedly discharge them below 50%, so I figure on realistically 220AH.

There's an explanation in our library of how to calculate how much battery capacity you need.

 

[geodrake]

Our coach has two twelve volt batteries in addition to one dedicated to the chassis.  We don't do a lot of boondocking and this has always been sufficient.

On our previous MH we had three coach batteries and three 150 watt solar panels. We boondocked at Padre Island National Sea Shore for two weeks, running TV and lights at night plus the water pump and refrigerator and ended up running the generator every three or four days to bring the batteries up. 

 

[Bryan]

Our coach has two twelve volt batteries in addition to one dedicated to the chassis.  We don't do a lot of boondocking and this has always been sufficient.

On our previous MH we had three coach batteries and three 150 watt solar panels. We boondocked at Padre Island National Sea Shore for two weeks, running TV and lights at night plus the water pump and refrigerator and ended up running the generator every three or four days to bring the batteries up.   

How many amp hours George?

 

[geodrake]

Bryan:
I can't honestly tell you.  I went to Sam's and bought two deep cycle marine batteries.  Same batts in both MHs. 

 

[Gary RV_Wizard]

A pair of 12v deep cycles will typically be 170-210 AH. The group 24 size is usually 85-90 AH each, while a group 27 size is 95-105 AH. Group 30 or 31's may be 110-120 each, but most retail stores don't carry that size.

 

[Tom]

Our group numbers are probably meaningless in the UK. It sounds like the previous owner installed an 85AH leisure battery, such as the Lumax L85 or the FLA85 that Electroquest sells.

When you replace, look for true deep cycle batteries such as the L110 that Numax sells. Their CXV27MF appears to be a "combination" deep cycle/starting battery that you'll see us refer to as a "marine" battery, and doesn't do a good job of either.

Alternatively, if can find a pair of 6V golf cart batteries, they're made for daily heavy discharge/charge cycles. However, I see that some of the "golf" batteries sold in the UK are intended for much lighter duty. The Trojan T-605, sold by Tayna would be excellent, although a little pricey, and would give you some longevity. A pair of T-605 connected in series will give you 210AH at 12V.

 

[Gary RV_Wizard]

Our group numbers are probably meaningless in the UK.

Shouldn't be, but what do I know?  ???  The battery group case sizes are standardized and BCI, the industry organization that maintains the standard group size definitions, claims to be international. BCI = Battery Council International.

http://www.batterycouncil.org/

And here is a list of the standard grooup sizes:
http://www.gglotus.org/ggtech/battery-bci/battery-bci-size.htm

 

[Bryan]

Thanks for the answer Tom, (does nobody else want to share THEIR current* battery capacity?)

I'm on my 5th RV now (in approx. 4 years) and have never had more than 240ah.  In the UK I think it is most common to use cheap FLA (Flooded Lead Acid) batteries in our RV's.  Not sure why but it is probably due to several factors (price, usage pattern, ignorance, familiarity).  Most seem to have 12v and not 6v too.  And the most common capacities are 85ah and 110/120ah with elecsol being popular.

I will seriously look at increasing our capcity next year although space is a little tight for more batteries.  Main reason is because I'd like to be able to last a weekend without needing to run the genny or have shore power.#

Anyway, how many ah do YOU have  ???

 

[Tom]

Bryan,

I forgot to mention that our prior coach had a pair of those 12V "marine" batteries I mentioned, which have a capacity of 105AH each (total 210AH). I've seen several other configurations on older and newer coaches, but I'll let others respond.

The capacity you need should be determined by the load you expect (how many watts for how many hours), and how long you expect to go before re-charging. Subject, of course, to space and budget limitations. Again, there's an illustration of how to calculate this, along with some examples, in our library.

There's nowt wrong with flooded wet cell batteries, and many of us have used them for years. They're cheaper than AGM, but they do have the downside of needing the water periodically checked and topped off as necessary.

 

[Just Lou]

Bryan,

I use two banks of 220ah batteries for a total of 440ah.  Each bank consists of two 6V batteries in series for 12V.  They are all flooded wet cell acid batteries for the reasons you mentioned, they are relatively cheap and I do have the room to accommodate them.

 

[Bryan]

Thanks guys.


I have been doing some research (including the 'search' button  ) and when I am looking to up my amp hours I think I will go for true 'deep cycle' batteries.  Cost will also be a factor but so will physical dimensions as this approach may give me more flexibility regarding where I can put them and therefore how many I can have  

I will do a proper audit at some point but by then I will probably know if I have enough or not.  We are away for new year dry camping (is that what you call it when you you don't have shore power?) with the 250ah so I will get a good picture of how much we use/need and how good my new charger is.

Bryan

 

[Tom]

..dry camping (is that what you call it when you you don't have sgore power?)

Aka boondocking.

 

[JerArdra]

We have Four 4Ds about 880 amp hours (equivalent to Eight 6V golf cart batteries).  Back in 2003 we were told that we were the first production Monaco coach (there was one test coach with four 4Ds) to get four 4D batteries because to do this Monaco had to move the two engine start batteries to the rear engine compartment first.

JerryF

 

[Terry A. Brewer]

Three  8D lifeline AGM's .... 750 amp hrs. RS 3000 PSW inverter with 150 amp charger.

 

[Mastermtn]

500 AH..

Fallriver 250 AH AGM monster...120 lbs, about 14" x 8" x 12" with
2000 W inverter and Honda 3000i generator set; 3 100 AH
deep cycle marine batteries with 1000W and 250W inverters...we are
retired, do mostly dry camping and this set up lets us
have sat tv, lights and computers all evening for several
days without recharging....we find an outlet at Forest SVC
CG's to recharge or let the honda run for 4-5 hours..downside
is long recharge time for the AGM..but worth it///also "requires"
AGM batttery charger with temp sensor on the postive post

Rich and S