House battery upgrade

[smlranger]

It became apparent that the two Deka 8D agm batteries in the coach were done. They would never reach full charge and would drop to 50% after only about 1/2 hour of running the inverter with nothing much on but the fridge.

I wanted to stay with AGM due to their truly maintenance free status so I shopped for the best deal on 6V AGM GC2 golf car batteries. The best 'price' were the Duracell AGM's at Sam's Club but they would not help with removal of the beastly 8D's. I ended up with Full River 224 amp hour GC2's from a local golf car dealer who had his techs remove the two 8D's and put the six Full Rivers in the coach for me. His price per battery was competitive (I had priced them in Myrtle Beach and another Full River dealer nearby).

I wired them up today after having some additional cables made up. I now have 672 amp hours. For the first time since I got this coach, the charger left the 'float charge' status and went to 'full charge' which is basically a stand-by mode. These batteries have a 2 year replacement warranty. They weight 65 lbs each vs. the 156 lbs each for the 8D's, so I can handle these if I ever need to replace them.

As you can see, one of these is on its side due to space constraints. One of the benefits of AGM is being able to install them in any position.

[vsheetz]

Looks good!

[Mr_D]

So about 330 amp hours of usable power if used down to the 50% point.

[camaraderie]

Sounds like an excellent deal and decision since you had the room! Full Rivers are still fairly new on the market but get good reviews. Pls. let us know how they do for you over time.

[CountryFit]

i recently replaced my 2 deka 908D's with 3 trojan j185h-ac deep cycle flooded. the 908d is heavy at 130lbs and i was merely able to move it out by hands, in spite of years of gym workout. the trojan j185h-ac is not lighter much, at 126lbs each. it's 12v with 225ah, exactly two 6v serialized. now i am having 675ah in total, hopefully good for 6-10 years... (i know a guy whose golf cart has 6 trojan t-105's. after 20 years he is still running it, although almost done).

[sallylillian]

AGM's are a great way to go if you have the real need for the flexibility.They take a huge charge, twice their capacity in general terms, so charging in bulk gets you up to 80% fast, they are also comfortable with the huge loads an inverter can place on them. In theory you can take them down to well below 50%, however you suffer in cycle life so I would always try to keep 50% as an absolute as the OP, but on my boat where I use them a lot, I try to work to 70%, but then I have 1800 amps of lifelines and I need a mortgage to replace that bank!

Michael
2008 Allure

[smlranger]

Originally Posted by sallylillian

AGM's are a great way to go if you have the real need for the flexibility.They take a huge charge, twice their capacity in general terms, so charging in bulk gets you up to 80% fast, they are also comfortable with the huge loads an inverter can place on them. In theory you can take them down to well below 50%, however you suffer in cycle life so I would always try to keep 50% as an absolute as the OP, but on my boat where I use them a lot, I try to work to 70%, but then I have 1800 amps of lifelines and I need a mortgage to replace that bank!

Michael
2008 Allure

I hope they are worth the cost. The six batteries and the new cables I had made up were a bit more than $1,500 . I have my AGS set to start the genny at 12.2 V so don't plan to routinely take them below 50%.

[camaraderie]

Originally Posted by sallylillian

AGM's are a great way to go if you have the real need for the flexibility.They take a huge charge, twice their capacity in general terms, so charging in bulk gets you up to 80% fast, they are also comfortable with the huge loads an inverter can place on them. In theory you can take them down to well below 50%, however you suffer in cycle life so I would always try to keep 50% as an absolute as the OP, but on my boat where I use them a lot, I try to work to 70%, but then I have 1800 amps of lifelines and I need a mortgage to replace that bank!

Michael
2008 Allure

All ya need is a 3600 amp charger to take full advantage of the 2x capability!

[sallylillian]

In principle yes, but the real benefit is that they stay in bulk a lot longer than wets, so you are pumping in amps at the full capacity of the charger whatever it is, whereas with wets it fairly quickly drops to absorption with the resultant drop in amps in. The plan when of grid is to limit generator running time, you want to get to 80% plus to have achieved anything and with AGMs and the biggest charger you can put in, mostly 100amps unless you parallel them up like the Victrons I have on the boat, you are going to get there in short order, not so with wets.
For interest, although we used to anchor a lot, we do not dry camp as yet whilst we get used to this motor homing lark, so when my batteries needed changing I just went for some half decent wets, but as the Xantrex was a pile of c*** I replaced it with a Victron and will be ready to swap to AGMs when and if we consider wild camping. Again for interest I like the Victron because apart from its many solid features I can plug the laptop in and set the charging algorithm to the exact battery manufacturers requirements.

Michael
2008 Allure

[becks]

Just put six Lifeline's in my coach, spendy yes, but I hope to have them a long time.

[Smitty77]

Our 04 Allure had enough battery compartment headroom to go up taller. So in the same foot print of the two Deka 8D AGM's, we were able to install four Lifeline AGM L16's. We had a single Deka 8D wet for chassis duty, also swapped out to a CAT 8D Maint Free, another CC owner on the Yahoo User Group tipped me off to look into the CAT, as it had a higher CCA rating.

House is now supported with 800AH capacity, which if we use our average high end daily consumption of 150AH, gives us two full days of usage. (We usually consume below the 150AH per day, so actually a bit more.)

A good charger, with temp sensor compensation, can go a long way on keeping your AGM's healthy. (Some units came out of CC without the Temp Sensor, so validate you have one, and order one if you don't have one.) Another tip from a different board, was that the older Xantrex charger AGM settings are not specifically what Lifeline recommends for Bulk/Absorb/Float settings. So we changed over to a Magnum PSW (wanted PSW for usage anyways), and it's charger settings has a AGM setting and then specifically a Lifeline AGM setting.

Our Solar Panel Midnight Classic 150 controller, allows for custom settings, so we set it to the Lifeline AGM values.

AGM's, Lifeline/Deka/etc., are expensive. But if well taken care of, and not drawn down too low of SOC - they should last a long time. While I did not mind the adding of water, we did have battery juice cancer in the compartment. So that is now refreshed and with the AGM just need to keep the dust out.

Best to all,
Smitty

[CountryFit]

This may not be related to the topic, but just to share with you in case it is useful - Prior to installing my Trojan J185H-AC, I did learn from other members and add 1 oz mineral oil to each cell (some recommeded 4 oz but if so I would have to take some fluid out to make the room. I chose not to). After two weeks, it appears work well - the batteries are clean and dry (in the past, after one week the battery cell vents would have been wet). Not sure if mineral oil has any long term impact to battery health but it has been used for the purpose for a long time. time will tell.

[sallylillian]

I agree smitty, a good charger and temp sensing, also sensing voltage at the batteries if possible helps. I do find it amusing when some people post about battery voltages without reference to the fact that its nearly freezing or up in the 90's!!
I found Jason at Lifeline to be a real source of advice, and their book on the battery management is a read every RVer should do.