Need suggestions on house battery replacement

[mchero]

Getting ready to upgrade my house batteries and thought I'd lay out my gameplan.

For 12 years I owned a 1993 Pace Arrow DP on an Oshkosh chassis. Shortly after purchased I replaced the 4 six volt house batteries. Approx 2005 I purchased 4 of the Sams Club golf cart batteries AND replaced the converter with a Progressive Dynamics 60 amp smart charger with the charge wizard. Got a good 9 years out of those batteries! To this date, new owner still using e same house batteries.

Two years ago we purchased the 07 Discovery. I found 4 Interstate 6 volts. http://www.atbatt.com/interstate-gc2-xhd-6v-deep-cycle-golf-cart-rv-battery.asp

Shortly after getting the beast home I discovered that the house batteries where not getting ANY charge. I felt the terminals and found one hotter than a Chernobyl reactor core. I replaced the interconnect, cleaned all cables and was good to go but also found a bad Aux start solenoid so I replaced it as well.

I have since installed 4 Gigawatt 250w high voltage panels. I have 2 strings paralleled flat on the roof out of any shade. Currently just outside of Lake Havasu on BLM land waiting to meet some other fellow RV'ers in a couple of days. Will move to the island Thursday for the Balloon festival then off to Quartzsite to the RV & Jem show.
Getting around 500 to 600 watts mid day. Been very happy with the Charge controller but just about done with the interstates! I have been careful to FULLY charge these batteries using the specs provided by interstate themselves. I have charged, check SOC with the hydrometer. I find everything within specs. No dead cells, no dry cells, appears to evenly require water.
Now that I'm ready to purchase have some questions. 1st option would be the Sams Club option BUT now that I have a nice solar setup I can install larger batteries. I can't go over 4, My battery bay is last bay on drivers side. They see ALLOT of dust dirt and water. I am always keeping them clean so wet cell is AOK with me. Now, Trojan have caught my eye, T105 would be a good replacement BUT I do have the height so POSSIBLY the larger/taller 300 to 400 amp hour batts.
Man, atbatt.com has some fanominal prices IF you can pickup at the warehouse. I have all the HW, crimper & such to makeup new, 2 gauge cables. Will keep them all the same lengths as possible & plan on having this rig for the next 10 years.
Any thoughts on the larger Trojans? Never knew anybody with those types of batts. I'll add more to this thread, want to explore B4 the sun goes down.

Thanks

[mchero]

grizzzman
I'm still on the fence about the L16's. I'll break out the tape & take some measurements. I'll throttle back the solar.
Running the genny tonight here at the Havasu Balloon Festival will give it a 3hr run the Xantrex should get them up to 14.6 Have to shut her down at 10:30PM
Landyacht
Thanks for the info.

[grizzzman]

mchero wrote:
Really confused now. Called Interstates 888 number & indeed was told 15.3 for two of the GC2-XHD 6 volts. It was a CSRE reading from the exact same link I was looking at. so who's ever on phones pulls up documentation

I went through the same thing a while back. Getting someone on the phone that knew what was/is going going on with the battery charging information was difficult. I finaly got a upper level person that admitted that the info was not correct.

I think you will do fine with Crown or Trojan.

[landyacht318]

I believe the 15.3v figures were for when USbattery was making the GC-2 batteries for interstate.

I do not think USbattery is making the GC-2s for interstate anymore.

My group31 USbattery required 15.3v daily after an hour or 2 at 14.9v, when cycled to 50 to 70% state of charge each night.

If it did not get the 14.9/15.3 regimen daily, but only a 14.8v for 3 to 4 hours, after about 6 cycles, Specific gravity would be in the 1.225 range and voltage under load that night would be abysmal.

The manufacturer specs was a good starting point but the hydrometer revealed higher voltage was needed for longer, and I got nearly 500 deep cycles from that 12v group 31 marine battery.

[mchero]

Really confused now. Called Interstates 888 number & indeed was told 15.3 for two of the GC2-XHD 6 volts. It was a CSRE reading from the exact same link I was looking at. so who's ever on phones pulls up documentation

[time2roll]

Absorb is closer to 14.8 with 15.3 as a finish charge IIRC.
I would stick with 14.6 to 14.8 volts absorption on new batteries.
If they are old, weak and gassy maybe 14.2 to 14.4 volts until you decide to replace.

[mchero]

7ofus
I was eyeballing a set of l16's just yesterday! Problem was, it was not a set, he only had three of the monsters! I had him take some measurments for me & I'll check my space.
My batteries are in the street side last rear compartment. Open to the road so it gets dirty in the battery compartment. I'm constantly cleaning them so checking water level is no big thing!
The place I visited had a smokin deal on those T105's but with 1K of solar I'd like the bigger batteries!

Red31 posted the link to the Interstate Site, it shows absorb at 15.3 as well. I'm told Interstate's numbers are incorrect. For as long as these batteries have been manufactured the numbers have been wrong?

[7ofus]

I am at 8.5 years on a pair of 440 amp L16s from NAPA. The last C20 test I did on them showed that they are still at about 90% of their original capacity.

I originally went with them because I had a lot of height, but only enough footprint for 2 batteries. They have been fantastic. If you can handle the height and weight, I believe they are the way to go.

[red31]

http://www.interstatedealers.com/pdf/201535.pdf

[mchero]

I'm simply reading the labels when I say interstate. I've herd the Mexico manufacturing story many times.
The Mexican batteries where in the coach prior to purchase so the most likely run flat. Nothing against Interstate. Just time for an upgrade. Will be seriously looking at Crown & Trojan.
Hard to believe Interstate would publish false numbers but you hear everything. Thanks for the additional interstate info.

[grizzzman]

mchero wrote:
Almot

Your looking at the wrong numbers.
Not getting enough absorb voltage when the Xantrex Freedom is charging via shore or generator!

I have 4 of the Interstate GC2-XHD-UTL
Take a look at this link & scroll down to the last chart, the 6 Volt section. 7.65 x 2 = 15.3
http://www.batteries-faq.com/activekb/questions.php?questionid=1
Now, If you pull up the PDF on the Xantrex Freedom 458 user manual you can take a look at the charge rates for wet cell.
http://www.xantrex.com/documents/Inverter-Chargers/Freedom-458/Freedom458(445-0193-01-01_rev-2).pdf
Note the Interstate data assumes 80 degrees.
The Xantrex Wet Cell charge rate at 80 degrees is Accept at 14.2
Interesting eh?
Now for solar I have 4 Gigabit 255 watt higt voltage panels in two paralleled strings. Midnight Solar 200 Light charge controller.
I set the accept voltage to 15.3 for a duration of 3 hours.
Wen I returned at 5:00 PM I found the controller in float! BUT I don't think I got a full 3 hours of absorb, some thin clouds moved in.

The numbers I'm looking at now are promising! I'll continue to let the charge controller juice them up.

While in Havasu sniffin around I did find a shop that had the T105's for $120.00 I was shocked! He also had some L16's in the 330ah range BUT he only had three! I got some measurements I will see if I can even get the big bastages in their! I don't know what he is going to do with three of them! I think he said they where about $300 a pop

Interstate battery does not manufacuture any batteries. Your battery is made in Mexico by a factory that was built by U S battery. It is a hybred battery, low Antimony positive plates and calcium negitive plates.

Now for the "fun" part. Interstate has posted the charging profile in a incorrect way. I suggest that you "do NOT" absorb at 15.3 volts. Absorb at around 14.7ish after the battery is charged then you clamp the amps at 3% of the C20 rate (232 ah would be 6.96 amps) and allow the voltage rise to 15.3. Most chargers used in RVs are not capable of doing this type of charging profile. Not controlling the amps correctly will cause excessive buckling and shedding of the positive plates (this is a mini equalize)
Find a profile that works with your equipment here. U S Battery charging profiles

[mchero]

Almot

Your looking at the wrong numbers.
Not getting enough absorb voltage when the Xantrex Freedom is charging via shore or generator!

I have 4 of the Interstate GC2-XHD-UTL
Take a look at this link & scroll down to the last chart, the 6 Volt section. 7.65 x 2 = 15.3
http://www.batteries-faq.com/activekb/questions.php?questionid=1
Now, If you pull up the PDF on the Xantrex Freedom 458 user manual you can take a look at the charge rates for wet cell.
http://www.xantrex.com/documents/Inverter-Chargers/Freedom-458/Freedom458(445-0193-01-01_rev-2).pdf
Note the Interstate data assumes 80 degrees.
The Xantrex Wet Cell charge rate at 80 degrees is Accept at 14.2
Interesting eh?
Now for solar I have 4 Gigabit 255 watt higt voltage panels in two paralleled strings. Midnight Solar 200 Light charge controller.
I set the accept voltage to 15.3 for a duration of 3 hours.
Wen I returned at 5:00 PM I found the controller in float! BUT I don't think I got a full 3 hours of absorb, some thin clouds moved in.

The numbers I'm looking at now are promising! I'll continue to let the charge controller juice them up.

While in Havasu sniffin around I did find a shop that had the T105's for $120.00 I was shocked! He also had some L16's in the 330ah range BUT he only had three! I got some measurements I will see if I can even get the big bastages in their! I don't know what he is going to do with three of them! I think he said they where about $300 a pop

[mchero]

Double post

[Almot]

- or wrong charger. Xantrex Freedom is an inverter-charger, not a solar controller, as I recall.

[2oldman]

-- batteries not charged