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AGM/Gel Cell life

Quote
Michelle wrote: "our 3 house batteries, which are 4 year and 1 month old Trojan AGM 8Ds seem to be tired."
The battery people (at A&D) here in Nacogdoches said their MK 8D gels routinely give 8-10 years of service, so it surprises me that the AGM's might not give similar longevity with the same maintenance. My two house 8D gels are in their 7th year and are still going strong.
Don Hay
'92 Grandvilla, U-280
The Hayfever Express
Build #4055
'97 GEO Tracker
Life is like licking honey off a thorn.

Re: AGM/Gel Cell life

Reply #1 –
Quote from: Don Hay –

The battery people (at A&D) here in Nacogdoches said their MK 8D gels routinely give 8-10 years of service,

We "lost" our original MK gels at 4 1/2 years old to problems with electrical service at a storage facility (repeated breaker tripping, no power charging the coach).  Not really sure why the replacement AGMs weren't more long-lived, except that we suspect the charge state ran way down once last year due to a combination of factors.  They seemed to deplete quicker than expected late last summer the two rare nights we boondocked (we had the genset on "auto") and today they were low after just 12 hours with nothing on, parked out front of the house overnight.

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

Lifeline AGMs and Link 2000

Reply #2 –
We lost shore power last night here at MOT during the rainstorm and ran a fan and other loads on our three Lifeline AGMs. By morning our AGMs had 140 hours remaining in them at the then load level (70 hours to take the AGMs down to 50% - I set my Link 2000 to the TOTAL amp-hrs: 3 x 255 = 765 ). Shore power dropped and returned two or three times and I disconnected from shore power when there were too many rapid power transients up to only 70 volts AC or so. Never bothered with the generator but did turn off the inverter.

In the morning after I connected to shore power the AGMs asked for 80 amps and dropped fairly quickly. In other words they were lightly discharged.

On the other side of things, before we bought it this U320 proved the concept that you should not ask your alternator to take the place of your generator or shore power to charge your house batteries after 20% or more discharge: Two alternators were burned up.....


best, paul
1999 U320 40' 1200 watts on roof. 12cf AC/DC Cold plate fridge/freezer. VMS 240 CL Honda Element

Re: AGM/Gel Cell life

Reply #3 –
I was pleasantly surprised with my two 8D gel batteries.  When I got the coach, they appeared to be on their last legs and did not hold a charge well at all.  Dropped off very fast.  I changed out the old Magnetek converter charger (boat anchor) for a new Progressive Dynamics 9270 with charge wizard.  Hooked it up last fall and left it charging the batteries 24/7.  Did not really give them a real test until we came back from Savannah, Ga.  Boondocked two nights on the way home.  Ran the furnace (in 30s both nights) and my CPAC breathing machine, lights, the TV and my laptop both nights.  Did not run the generator to charge up during the day.  The gel 8Ds held up great both nights.  And here I thought I was going to have to replace them this spring.  Now I am holding out to see how much longer they will last.  Know that they are not original, but the original owner did get them installed in the early 2000s.  Will have to look for the receipt now to see how old they are.
1994 U225
build #4514

Re: AGM/Gel Cell life

Reply #4 –
Boy, talk about a timely post. The interim owner of my RV installed lead-acid batteries for the house batteries and I thought I would change them before this summer, but the storage facility has a current limiter for just trickle chargers and other tenants plug in appliances or equiment and flip the breaker, causing down-time when I had the boost switch on to boost the starting batteries. Yep, both house and starting batteries deader than a doornail. I have been nursing a trickle charger to see if I could recover, but starting batteries won't get higher than 11.5V. Not good. Haven't tried jumping yet, but have no info in case I have to buy six -count 'em - six batteries shortly so that some family dry camping this summer doesn't disappoint. Would hate to be at yellowstone with brother's family who flew in and not have ability to start or use house batteries reliably for extended period. Called FT and was told that starting batteries on my 1999 U320 were 3 Optima and I thought "Red Top", but when I look at Optima site and click on RV - it suggests "Blue Top". Was also told that originally, House used two or three (cables for three) MK brand 8D Gel cell, but FT now uses Deka 8D, either of which are supposed to be fine. Could anyone provide experience and recommendations? When I look on Deka website, I see under AGM series (not Gel Cell) an 8D Group and part number 8A8D, but if the series is the 8D, how should I distinguish between the the numbers inbetween the 8**D. - ditto same issue on MK brand. I only downloaded 1 inch of "light reading" at lunch today, so would appreciate a quick response as to what others have for both starting and/or house batteries. Any advantage to Optima, maybe different types(?) for both, or do others have recoomendations? Wife won't like prices, but battery problems on boat REALLY turned her off and I do not want same experience with RV.
Hugh & Judy Taylor
w/ Gator
Richland, WA
36 Ft - 1999 U320

Re: AGM/Gel Cell life

Reply #5 –
Hugh and Judy,

When I bought my coach five years ago the former owner had installed two red tops and one blue top for chassis batteries.  they continue to work just fine.  The specs look about identical.  I don't think it makes much difference which you choose, but get them all the same if you can.

Get the 8A8D coach batteries.  The 8A4D's are lower capacity.  Make sure you get the right posts, which are SAE.  I got DEKA gels for the coach. 
Regards,
Brett

'99 42' Foretravel Xtreme
'14 Brown Motorsports Stacker
'05 Chevy SSR
'02 BMW R1150R

Re: AGM/Gel Cell life

Reply #6 –
Deka & MK are made by the same manufacturer.  I personally like the gel technology because of the number of charge cycles it can tolerate.  My current MK gels are 6 years old and going strong. Thhe engine uses two Optima Red's which are now 7 years old.
 
I've posted in this forum previously that I disconnect the batteries when in storage.
Peter & Beth Martin
No Forrest? What have you done?
MC# 15890 until Dec 2016; FMCA #F329677
Cincinnati, OH

Re: AGM/Gel Cell life

Reply #7 –
With all the talk about batteries, I think it would help all of us to go back and read the poop sheets by Phred, I do not have the url in my new computer,but you can google it, it has a lot of info on batteries and other electrical issues.
The selected media item is not currently available.Bill&Doris 97 U270 36'
University of Parris Island Class of 66
Semper Fi  Build# 5174 MC#17094

Re: AGM/Gel Cell life

Reply #8 –
Quote from: Bill Willett –
With all the talk about batteries, I think it would help all of us to go back and read the poop sheets by Phred, I do not have the url in my new computer,but you can google it, it has a lot of info on batteries and other electrical issues.

Batteries -- and Other Electric Stuff by phred
The selected media item is not currently available.Barry BEAM #16014
2003 U320 40' AGDS
Beamalarm, Foretravel technical help and specifications
"Whatever the mind can conceive and believe, it can achieve"

Re: AGM/Gel Cell life

Reply #9 –
Quote from: pypedreamer –
I have been nursing a trickle charger to see if I could recover, but starting batteries won't get higher than 11.5V. Not good. Haven't tried jumping yet,
Get them hooked to some type of smart charger.  The 3 stage charger of the Progressive Dynamics converter charger that I installed is, I believe, what saved my batteries.  The old style converter charger is what overcooked them.
1994 U225
build #4514
 

Re: AGM/Gel Cell life

Reply #10 –
If you are going to boondock/drycamp with your unit I would go with the DEKA 8G8D gel batteries. I would also add at least 480 watts of solar (600 watts would be better) to your roof to be able to adequately charge them as you will not be able to do it otherwise unless you are plugged in someplace. The gels have double the cycles of an AGM. Set your inverter/charger correctly and adjust your alternator.

Regards,
Jon Twork
JON TWORK KB8RSA
Full Time RVer (10+ Years) & Dedicated Boondocker
Retired, Unemployed, Homeless Transients
1996 Foretravel U270-36 w/24' Timberwolf Trailer
I firmly believe that tomorrow holds the possibility for new technologies, astounding discoveries, and a reprieve from my remaining obligations.
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