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Battery size question

Hi,

Another Newbie question.  Why are the coach batteries on the GV the big semi truck size batteries rather than the same size as the deep cycles on my previous 5th wheels?  I understand the engine battery being that size.

Just curious as that is a big difference in cost
Dan 1989 U280 40'

Re: Battery size question

Reply #1
Lot of different ways to go with batteries, both engine and house. I replaced my two 8D house batteries with six solar application deep cycles. Several other choices from 8D batteries from Sam's Club at a little more than $100 each to multi $100s for sealed high end batteries. Six volt golf cart batteries are a favorite with many. Just depends on how much room you have and how much work you want to do to the racks. Many good web sites for advice, especially if you intend to dry camp a lot.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Battery size question

Reply #2
Take good care of those batteries... they will be expensive to replace no matter what you decide to replace them with. Check your charger/converter and if it is not one of the modern 3-stage versions (e.g.: Progressive Industries) I'd suggest that the next upgrade you do would be that. About $150 at Amazon for a 50-amp charge unit. You can combine inverter and charger/converter if you choose... I didn't.

Modern converter/chargers are much more than "trickle chargers"; the original equipment charger/converters on almost all RVs built before about 2000 are notorious for boiling out the batteries. The 3-stage units carefully monitor the battery voltage and will keep your battery bank operating for years. Assuming, of course, that it's not too late already. We were lucky in that the previous owner had bought new batteries just before we took delivery on the coach.

The charger, by the way, is in one of the crappiest spots. On our 1993 U225 it's behind the entry stairs which is only accessible by laying full-out in the basement accessible from the driver's side.

Craig
1993 U225 36' Unihome GV with PACBRAKE exhaust retarder, Banks Stinger and Solar Panels.
Toad: 1999 Jeep Wrangler 2-door soft-top.

"No one has ever had to evacuate a city because the solar panels broke."

Re: Battery size question

Reply #3
With Craig on the 3 stage converter/charger.  My old school converter/charger finally did my GEL cell 8D batteries in.  I converted to a Progressive Dynamics 3 stage converter/charger and managed to get another year out of the GEL cells but they were pretty much goners.  Converted them out to new 8D AGM batteries.  Expensive but they keep me powered for several nights when not on shore power.  Than include running my CPAP breathing machine.  Hoping to get 8 to 10 years out of them.  My compartments aren't as high as the U280s and maintaining wet cells was not easy and I felt the AGMs were a better choice for me over GEL batteries.  If you want to read up on the different battery choices, here you go:  http://www.dekabatteries.com/assets/base/0139.pdf
1994 U225
build #4514

Re: Battery size question

Reply #4
the original equipment charger/converters on almost all RVs built before about 2000 are notorious for boiling out the batteries.

Thanks for the replies.  I have a new PD9280 ordered already.  Original converter has ruined the coach batteries and I'm in the process of replacing and was wondering why the Foretravel needed the coach batteries to be the "truck" type batteries or if the smaller marine deep cycles would be sufficient.

Seems like I'm getting a crash coarse on all the Foretravel necessary upgrades at once...$$$
Dan 1989 U280 40'

Re: Battery size question

Reply #5
Quote
the original equipment charger/converters on almost all RVs built before about 2000 are notorious for boiling out the batteries.

Starting with the 1995, Foretravels came standard with a Heart 2500W inverter incorporating a modern 3 stage 130 amp charger. As the standard batteries were maintenance free gel cell the desulfating option is disabled.
The selected media item is not currently available. Dave Head & Megan Westbrook
Titusville, FL - The Great Outdoors
'98 270 buying this month
Toad is a 2018 F150 XLT

Re: Battery size question

Reply #6
Starting with the 1995, Foretravels came standard with a Heart 2500W inverter incorporating a modern 3 stage 130 amp charger. As the standard batteries were maintenance free gel cell the desulfating option is disabled.
Our 1997 coach still uses the OEM Freedom 25 (Heart 2500W) inverter/converter to maintain three 8D size AGM batteries. The three big batteries fit nicely in steel shelves that slide out on bearings. The three big batteries and big inverter allow us to briefly use the microwave oven or toaster oven without firing up the generator during lunch stops on the road. They also provide plenty of capacity for quiet nights when air conditioning is not required.

The OEM control interface shows the progress of the 3-stage charging sequence with indicator lights. The voltage, current, and amp-hour values are available as well.
J D Stevens
1997 U295 CAI 36' Build #5085
2002 Subaru Outback
Motorcade 16869
Bellville, TX

Re: Battery size question

Reply #7
Has anyone been investigating Lithium Lipo4 batteries. I suspect in the next few years they may (I hope) become more mainstream and that the price will drop. They sound great with 80% less weight, 90% draw down and linear power drops and 3000 cycles. But from what I can find a 8D is about 1600.00!
1999 U320
Mount Dora Fl

Re: Battery size question

Reply #8
Has anyone been investigating Lithium Lipo4 batteries.

Phil,

There have been several threads on LiFePO4 batteries in the past year or so.  Here are a couple I came up with doing a quick search for lithium batteries on the forum.  Besides the cost of the batteries, one needs to factor in an inverter/charger that is compatible.

Lithium Iron Phosphate batteries

Lithium Iron Phosphate Batteries (was House Battery Replacement)
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: Battery size question

Reply #9
Hi,

Another Newbie question.  Why are the coach batteries on the GV the big semi truck size batteries rather than the same size as the deep cycles on my previous 5th wheels?  I understand the engine battery being that size.

Just curious as that is a big difference in cost

I have been intending to get to this subject for a while, it creates an itch that I want to scratch.
First, let me talk about something I know a little about - wet-cell batteries.

I had eight Trojan-105 6 volt Golf Cart batteries in my house bank. Each one was rated 220 amp-hours so each series pair gave me 220ah @12 volts. There are several batteries from different manufacturers that have the same specs. Three of the GC size batteries will fit in the same footprint as the 8D (also ~220ah). Also, I find that moving 65 lb lead boxes around in the depths of the batt compartment is much more possible than 140 lb lead boxes.

I started looking at the battery offerings from one relatively large manufacturer (Canadian I think, I got the name from another FF post but haven't found it again).
It looks to me like there are several AGM batteries which would give me the same 3 GC for 1 8D footprint. It seems to me that you could increase the house bank capacity by 50% without structural changes and possibly for less money.

When I get settled after the summer's trip I'll finish the analysis.

elliott
Elliott & Mary Bray
ex. 1996 36' U295 - Build 4879
ex. 2018 Coachmen Leprechaun 319MB
 

Re: Battery size question

Reply #10


I started looking at the battery offerings from one relatively large manufacturer (Canadian I think, I got the name from another FF post but haven't found it again).
It looks to me like there are several AGM batteries which would give me the same 3 GC for 1 8D footprint. It seems to me that you could increase the house bank capacity by 50% without structural changes and possibly for less money.

Elliot,

Could it be Mastervolt's slimlines?  AGM-SL 12/185 | Mastervolt Marine 

Looks like Rudy might be a good resource on Mastervolt Master Volt 8D AGM batteries

I also recalled GregoryS installed Northstar AGM 185's (also a slimmer battery) in his Designer Series a little over a year ago 
More battery issues 

NorthStar - Extend Battery Life and Save Energy

Michelle
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320