Anyone running dual auxiliary batteries?

[DougB]

Hello all,

My family and I sometimes go camping for longer periods of time, and on one occasion (even with a solar panel) I ran out of battery power for my Engel SR48F fridge. Right now I have a single Optima yellowtop battery (D34, I think) but was thinking on going with two of the thinner D31A batteries, on their sides and stacked. Anyone have a setup like this, or a different setup that might extend my battery life? The goal is to have the aux battery/stack still fit on the left side aux battery tray in the engine compartment, without modifying the existing spare tire bump.

Thanks!
- Doug
_________________
'75 Campmobile (tin-top to SpaceRoof)
'73 Fastback
'52 BMW R67/2
'41 Zundapp KS600
'55 Puch SGS250
A very, very understanding wife

[BayCreamPuff]

You could do 2 x 6V 225Ah golf cart batteries in series.

That'll give you 12v @ 225Ah. The yellow top is 55Ah I believe.
_________________
Cream Puff
'79 CA Stock FI Deluxe Campmobile

Earl Grey
'87 GoWesty 2.2 Westfalia

Marsha Mellow
'00 Eurovan VR6 Full Camper

[gintaras]

I have 2 AGM 100A batteries installed under my seat..
_________________
1979 Deluxe Westy in Mexico Beige

[DougB]

Definitely not looking to take up the underseat area as that's being used for something else. I may look into the dual 6V battery option. Any other ideas?
_________________
'75 Campmobile (tin-top to SpaceRoof)
'73 Fastback
'52 BMW R67/2
'41 Zundapp KS600
'55 Puch SGS250
A very, very understanding wife

[aeromech]

Dual 6 V golf cart batteries works well. My buddy has that in his motor home. What works better though is a good old fashion ice chest. Keeps the beer colder.
_________________
Lead Mechanic: San Diego Air and Space Museum
Licensed Airframe and Powerplant Mechanic
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Boeing 727,737-200-300-400,757,767
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VW Type 2 1971 (3 ea.) 1978, 1969
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Capable of leaping tall buildings in a single bound

[DougB]

Hahaha, true, not sure I can get the kids to survive solely on beer for that long, though. Me, though...I'd be fine with that
_________________
'75 Campmobile (tin-top to SpaceRoof)
'73 Fastback
'52 BMW R67/2
'41 Zundapp KS600
'55 Puch SGS250
A very, very understanding wife

[pittwagen]

Have you considered mounting dual AGM batteries midship under the floor. Optima yellow tops on their side in some nice sealed battery boxes, for example.

[DougB]

Under the floor is an interesting idea...there are some decent brackets available for the thinner Optimas, like this one:

http://www.ebay.com/itm/301949748350?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

Seems like it'd be possible to mount them between frame crossmembers pretty securely...still, though, not sure that I love the idea of them exposed to the elements under there.

I measured the left side battery tray area and it looks like I'd be able to work with a battery that's around 13" x 9" x 7" (this last measurement only so low because of the spare tire bump. Now I'm thinking that this battery might work:

http://www.ebay.com/itm/SLR125-VMAX-AGM-Deep-Cycle...SwdIFXyc9J

Anyone use one of these? Sounds like they're made in the US. I'd probably use it on its side with the terminals pointed toward the engine. I know that's possible with AGM batteries from the electrolyte perspective, but wonder if the plates can take sideways force of bumps and such.

Thoughts? Thanks!

- Doug
_________________
'75 Campmobile (tin-top to SpaceRoof)
'73 Fastback
'52 BMW R67/2
'41 Zundapp KS600
'55 Puch SGS250
A very, very understanding wife

[pittwagen]

With my idea the elements are not a factor. The battery box would be sealed.

As well, if you look at the Optima site, they even suggest a sideways mounting solution.

[DougB]

Ah, ok...I'd have to see what sealed battery boxes are available that would be structurally sound enough to act as the mounting for a heavy battery. I wonder if ammo cans would be a possibility. They could be vented, are certainly sealed against the elements, and seem structurally rigid enough. Perhaps I could keep my existing Yellowtop battery in the engine compartment (until it gives out), then mount the additional two underneath and bring the battery cables up to meet the existing aux battery (and the charging cables from the solar panel).

That said, I'm still leaning toward that VMAX battery as a simpler, single-battery solution (that would end up being about 1/3 - 1/2 the cost of 2 new Optimas for just a little less in the way of Amp Hours/Reserve Capacity.
_________________
'75 Campmobile (tin-top to SpaceRoof)
'73 Fastback
'52 BMW R67/2
'41 Zundapp KS600
'55 Puch SGS250
A very, very understanding wife

[pittwagen]

The battery you are suggesting should be enough to power a fridge for a couple of days. I don't remember but you have a stationary solar panel, right? I went with a portable unit so I could get the best possible charge and still be parked in the shade. Maybe a solar panel addition?

I am not a big fan of added batteries in the engine compt. Heat! That being said I installed a BN4 so the battery idea on the left side is a no go.

[ac78]

Hey Doug- What did you end up going with? I've been on the hunt myself and wondered if you have feedback from the VMAX?

I'm only running a Aimes 1250 watt 10.4 amp inverter so I'm not sure I need to go too crazy on the battery unless I look at upgrading to a 2500 + watt inverter too...
_________________
78 Westy 2.0l hydr. FI

VW Campmobile
For people who believe a family's
car should be it's castle !

[DougB]

Hey! Yes, I did end up going with the VMAX and it's been great so far. During the summer months I could run the fridge indefinitely just from the single solar panel charging both the starting and VMAX batteries...and the second panel I added (slides out from over the other solar panel on drawer slides) would increase the power input. The main caveat is that the battery it too big to stand upright inside the engine compartment under the spare tire well...I have a Westy so that well is pretty much useless for me, so maybe someday I'll replace it with a top-loading battery hatch...but in the meantime I have the VMAX installed on its side, which is totally fine based on info from the manufacturer.

- Doug
_________________
'75 Campmobile (tin-top to SpaceRoof)
'73 Fastback
'52 BMW R67/2
'41 Zundapp KS600
'55 Puch SGS250
A very, very understanding wife

[kguarnotta]

Hi, I am interested in this battery thread. I've got a aux battery, and was thinking of ways to get it to last longer. I don't know if I want to go with the full solar panel options - would this sort of battery work with just charging from driving the bus? Or using the built in charger, and plugging in overnight?
_________________
-Kevin
Lincoln, MA

'86 Triple Knob Syncro w/EJ22
'78 Westy
'69 Single Cab
'65 Kombi - EZ-Camper

[ac78]

After trying the Group 31 Marine 92 amp/hr and failing becuase it was 13" long and 9.5" high, I ended up with a Duracell Dual Purpose AGM Group 65 75 amp/hr which is about 11" long and 7.5" high. It actually fit real nice. I was originally going to get the Group 34 but it only had 55 amp/hr. I also looked at 2 6v batteries but couldn't come up with the right size to fit.

I have an Aims INVPWR 1250 with 10.4 Amp max so I feel that should run a decent fan and lights etc for the night.

The thing I felt was the most interesting is that the Sam's Marine batteries had almost exact spec and description as the same Group Car battery but half the warranty. Batteries Plus also has the same Duracell available but the manager said he had no idea how they were selling them that cheap. At first he was saying how much better his batteries were, but when he verified the models I showed him, he was almost speechless.

I'll try to remember to report back on how much I ran for how long with this battery.
_________________
78 Westy 2.0l hydr. FI

VW Campmobile
For people who believe a family's
car should be it's castle !

[kguarnotta]

I looked into this - I guess the Platinum Battery has been discontinued -as per the Auto guy at Sears.

I see Batteries plus carries it still.

I also found this one - Bosch S6585B S6. Specs look good (better than the Duracell) It is a bit longer, but I think it will fit. I dropped my old optima off to be tested - if its bad, then I think I'll go this way.

I also have a call into VMAX about their battery, to see if would work for my westy. IT looks like I'd have to mount it sideways to get it to fit, and I'm not sure how I'd strap it down. But the AH are a lot more - so may be worth trying to get it to fit.

By the way - how much does the fridge draw when running?
_________________
-Kevin
Lincoln, MA

'86 Triple Knob Syncro w/EJ22
'78 Westy
'69 Single Cab
'65 Kombi - EZ-Camper

[sodbuster]

I managed to get this Optima 31T in position with a little finagling of the battery tray. I fit fine without the tray but I wanted the tray as part of securing the battery hold down. Works great so far for everything I have needed it to do.

[kguarnotta]

My previous optima was an optima Blue top - D34. Which worked ok - I think it is dead, waiting to hear back from my mechanic.

My testing said it was dead. I asked him to double check. It was about 4.5 years old. I didn't take great care of it. I didn't realize it was important to keep them on a trickle charger in the winter when I'm not driving my bus.

I thought I'd read to use the blue top for the aux battery and the yellow top for the main battery.

Also - I was able to use the original clamp to hold the battery in place.
_________________
-Kevin
Lincoln, MA

'86 Triple Knob Syncro w/EJ22
'78 Westy
'69 Single Cab
'65 Kombi - EZ-Camper

[ac78]

[kguarnotta]

A quick look at the Optima site:

The REDTOP high-performance AGM battery is the ultimate starting battery and is designed to deliver a strong burst of ignition power for a reliable start-up every time.

The YELLOWTOP high-performance AGM battery is one of the few true dual-purpose automotive batteries available

The BLUETOP is a high-performance AGM battery with exceptional running time and more recharges than you’d get out of a traditional battery.
_________________
-Kevin
Lincoln, MA

'86 Triple Knob Syncro w/EJ22
'78 Westy
'69 Single Cab
'65 Kombi - EZ-Camper