Journey house battery replacement advice needed

RCtime · 06-24-2009, 04:56 PM

My Journey came with 3-12V. deep cycle batteries for the coach side of the elect.
I presently have 2-6V deep cycle batteries that just dont do the job anymore.
Wouldn't I be better off going back to the 3-12V deep cycle batteries.
I really dont do any boondocking and need 12V for more than 2-3 days., if that.
4-6V deepcycles would be the optimum I know, but not sure they would fit without modifications.
Just how much more would 3-12V. give over my present 2-6V batteries.
The previous owner of my coach installed these 2-6V batteries to save a buck I guess.

SteveG · 06-24-2009, 09:12 PM

I have not opted for the 6 volt series setup for the same reason you are considering. I do almost no boondocking and have power available to keep my three deep cycle batteries charged when stored with the three stage charger that came with our Journey. I have had good luck with this setup so far. For the house side I use Interstate batteries 29M. This setup probably matches your charger capacity.

Others have some great charger and battery setups using more sophicasted chargers and batteries but such setups do not fit everyones budget.

Regarding the 6 volt golf cart battery setup vs 12 volt deep cycle, others may have to answer that. My general understanding is that those who have made this conversion changed the 3 deep cycle 12V batteries for four 6volt batteries set up in series- parrallel.

I think that typically two 6 volt bateries @ 220 amp hours each connected in series results in a total output of 12 volts @ 220 amp hours. Two deep cycle batteries at 12 volts @ 105 AH each connected in parrallel results in a total oupput of 12 volts @ 210 AH.

Using the above explanation for your situation, three 12VDC 105 amp hour batteries in parrallel will yield 105 x 3 = 315 amp hours. The four 6 volt batteries in series-parrellel will yield 220 amp hrs + 220 amp hours = 440 amp hours. So you see why those that boondock use the four battery 6 volt set up. More bang for the buck. Along with the stronger design setup of the six volt battery makes them an attractive solution.

I think I've got the basics correct. Hopefully, others will provide you a more sophicasted analysis.

smlranger · 06-24-2009, 09:17 PM

I replaced my three original 12V batteries with three new 12V Interstate deep cycles. They have held up for 3 years. When I need to replace these, I may consider going to four 6V golf car batteries. A number of folks with the Journey have determined that the taller 6V batteries will fit in the tray with just enough clearance.

Like you, we don't boondock much...our 'boondocking' consists of an occassional overnight in a Walmart lot. With any of the lead-acid batteries, the real issue with our trays is the trouble getting to the batteries in the middle and rear of the tray to check/add water. I installed the Qwik-Fill system which has worked very well. Not sure the Qwik-Fill system would work with the taller 6V batts due to tighter clearance.

You can do the amp hour math but I suspect 3 12V batteries will give you more juice than 2 6V, but 4 6V will exceed 3 12V.

Sammie · 06-24-2009, 09:31 PM

I just recently made the 12 volt to 6 volt conversion in my 2006 Journey. It's a tight squeez but four Trojen 105s fit. I like the added capacity for dry camping. See my thread with pictures.

http://www.irv2.com/forums/f101/jour...ion-52584.html

SCVJeff · 06-25-2009, 01:04 AM

Been there, & done did it. I have 4ea. U2200's in the tray, and it JUST fits! I have a couple of 2x4's cut to length in the front to keep them from sliding since I haven't figured out a bullet-proof way to hold them in. I figure if I hit something that causes me to bounce a battery up 4+", I have way bigger problems anyway.

You also may want to trim the top flashing up a little to give adequate clearance to the tray. It's cosmetic and only seen when the door is open but keeps +12V off the chassis (bad). As far as capacity, with the 4th 6v battery, I have the equivalent of 4ea. GP29's (the coach came with 3).

Also FYI: I spent quite a bit of time chasing down the original shop drawings and structural specs of this tray since these batteries are significantly heavier than the OEM's. Kwikee finally retrieved them and said the tray is rated @ 250lb. I'm +4lb over

Also if you decide to do this, I would suggest propping the tray when loaded and extended to save your feet, just in case. Here is what I use.

skigramp · 06-25-2009, 10:20 PM

We have a 2004 Journey. I am on my third set of house batteries. We never boon dock anymore.

I currently have 3 Walmart (EverStart) 24DC-6 house batteries ... they are working just fine.

If you switch back to 3 12 volt batteries in parallel make sure that you hook them up correctly to cut down the internal resistance of the three battery bank.

Here is a thread that will get you started (it shows two and four battery banks)

Look Here

There is a "mistake" in the diagrams. They show only one set of connectors to your batteries. There are really two sets of connectors to the battery bank: Charging , Pick-Up.

For Charging (from your alternator) the plus wire goes on the top battery in the diagram and the ground goes on the bottom battery in the diagram.

For Pick-Up (to the house / invertor) the plus goes to the bottom battery and the ground goes to the top battery.

I hope this information is helpful to you

SteveG · 06-26-2009, 09:36 AM

Skigramp, you said "If you switch back to three 12 volt batteries in parallel make sure that you hook them up correctly to cut down the internal resistance of the three battery bank."

I would have initially said electrically the connection points do not matter. But you are saying that the connection points matter because connecting them to three 12 volt batteries provides less internal battery resistance. Out of curosity I did a search trying to further understand the why and found the following explanation of how to best connect four 12 volt batteries in parrallel.

To see the battery connection images you will need to go to the web site http://www.reuk.co.uk/Interconnectin...ttery-Bank.htm
For any off grid renewable energy system the battery bank is probably the most important component. It doesn't matter how much power you generate - if it is not stored safely and efficiently then you will have no electricity when you need it. Batteries are also one of the most expensive parts of wind, solar, and hydro power generation systems so they need to be well cared for.

Unless you have a very small system you will need more than one battery - therefore you will need to connect the batteries to one another to form a battery bank. Below is an illustration from SmartGuage Electronics showing how this is often done:

The Problem

Because of the small amount of resistance in the cable used to interconnect the batteries, and from the connection between the cable and the battery posts, the battery closest to the installation is charged the most, discharged the most, and worked harder, whereas the battery furthest from the installation is charged the least, discharged the least, and worked the least.
The Reason

The power from the bottom battery has to pass through the main connection leads whereas the power from the top battery has to pass through the main connection leads and another four sets of interconnecting leads. Although the resistances are tiny - it is the fact that they are so small that makes them have such a big effect on the current flowing to each battery.

SmartGuage Electronics used a computer simulation in 1990 to calculate the following assuming a battery internal resistance of 0.02 Ohms, interconnecting lead resistance of 0.0015 Ohms per link, and a total load on the batteries of 100 amps:

The bottom battery provides 35.9 amps.
The next battery up provides 26.2 amps.
The next battery up provides 20.4 amps.
The top battery provides 17.8 amps.

...which means the battery closest to the installation is worked twice as hard as the battery at the top of the battery bank! These surprising findings have since been reproduced in real world situations.
Connecting Batteries in a Battery Bank

So it the example given above shows you how NOT to connect batteries to make a battery bank, how should you do it? It is actually very simple - instead of taking the negative AND positive feeds from the same battery (in the example above it was from the bottom battery) , you should take one feed from each end of the interconnected battery bank - e.g. +ve from the top battery and -ve from the bottom battery. See the image below from SmartGuage Electronics:

With the same example load of 100 amps presented above the new loads on each battery are as follows:

The bottom battery provides 26.7 amps.
The next battery up provides 23.2 amps.
The next battery up provides 23.2 amps.
The top battery provides 26.7 amps.

To get the batteries perfectly balanced requires a different scheme involving a little more work and expense (more cables and connections required), but is only really necessary if you have very expensive batteries or a more than 6 or so batteries in your bank.

The chargers should always be connected to the same points as the loads. Without exception.

RCtime · 06-26-2009, 01:21 PM

I have certainly got a lot of info, my head is swimming. I will need to purchase at least a couple more cables and hook up as recommended.
I have been to the elect. diagram from winnebago, but it is hard to see, although its seems they have it wired for less internal resistance. (I think)
I would have never thought twice about the internal resistance in a battery pack.
Skigramp, a digital picture of your 3 battery hook up would be appreciated.

SteveG · 06-26-2009, 01:27 PM

Here is a photo of our three battery bank from our 2004 36G Journey

RCtime · 06-26-2009, 03:36 PM

Perfect, thanks Steve. I just got back from Sams club and am going with their 12V deep cycle RV Marine battery. $68.75 apiece. plus your trade in.
215 amp. hr.. I have to get an extra set of cables for the 3rd. battery
They are group 27 battery.
Your cables look heavy duty, so I will take one of mine along with me when I get them. I guess a good auto parts store.

SteveG · 06-26-2009, 03:43 PM

RCtime, I had my cables made up at the Intersate Battery dealer. I took a sample of the size which included the lug size. I did that because I had a length problem. I haven't shoped for them in an auto store but it would seem that NAPA might carry something you can use; probably be able to also make them up to size.

RCtime · 06-26-2009, 05:58 PM

Thanks Steve. I do have an Interstate dealer fairly close. I will go there.

RCtime · 06-26-2009, 06:43 PM

OK, just one more dummy me question.
When I remove my batteries for exchange and take my battery cable for reference to make some new ones.
Should I cover up the 10 W. solar panel on the roof so it will not be doing its thing?

SteveG · 06-27-2009, 02:44 PM

RCtime, yes, I covered mine. Not much power comes from that small panel but why take any risk when it is so simple to do. I also hit the disconnect switch, wrapped each lead end that was left dangling in electrical tape. I figured it was over kill but I am not big on surprises developed in ignorance. Also a good time to add corrosion protection to the posts.

Also a good time to figure out how you're going to service the rear most battery. Dog gone tray doesn't pull far enough out to be able to even inspect the battery port. I used a small mechanics inspection mirror (mirror hinged on handle) and a flash light for a while. And various cup and hose combination's to fill the port but eventually I added the fillers. They work OK and I have had no trouble with them. And you don't have to worry about knocking debris into the battery port while your struggle with filling it. But I've seen other solutions. Just have to find something that works for you.

RV'nOldTimer · 06-30-2009, 08:29 PM

Quote:

Originally Posted by RCtime

Perfect, thanks Steve. I just got back from Sams club and am going with their 12V deep cycle RV Marine battery. $68.75 apiece. plus your trade in.
215 amp. hr.. I have to get an extra set of cables for the 3rd. battery
They are group 27 battery.
Your cables look heavy duty, so I will take one of mine along with me when I get them. I guess a good auto parts store.

RCtime,

I know this question is not timely, but, are you assuming that your RV/marine batteries are true deep cycle type? Most labeled RV/Marine are compromises between a starting battery and a deep cycle. They may, in fact, be a good choice if you are running a high capacity inverter which needs to have one or two hundred amps available.

Just asking.

JT Kirby

RCtime · 07-01-2009, 07:39 AM

JTKirby
I hav'nt a clue if they are true deep cycle. I do know they say deep cycle and are definately not a true starting battery.
How does one know in a 12v. battery?
I would think the 6V golf cart type battery would be close as you could get in a true deep cycle for rv use.
I hav'nt actually purchased them yet. I have to get down to the motorhome 1st, and remove my old ones to take in as trade. a dog gone cold got hold of me and slowed me up a little.
If you have a definate 12V deep cycle brand in mind let me know.

RV'nOldTimer · 07-01-2009, 09:33 PM

Quote:

Originally Posted by RCtime

JTKirby
I hav'nt a clue if they are true deep cycle. I do know they say deep cycle and are definately not a true starting battery.
How does one know in a 12v. battery?
I would think the 6V golf cart type battery would be close as you could get in a true deep cycle for rv use.
I hav'nt actually purchased them yet. I have to get down to the motorhome 1st, and remove my old ones to take in as trade. a dog gone cold got hold of me and slowed me up a little.
If you have a definate 12V deep cycle brand in mind let me know.

First, I suggest you read this:

http://www.windsun.com/Batteries/Battery_FAQ.htm

(may need to copy and paste to make citation work)

It will explicate what I'm trying to say. Look at the section on deep cycle batteries.

Yes, true deep cycle 12 v batteries are hard to find and to identify from a label if/when you find them. Some RV'ers report finding them at large boat supply houses. I have bought them from an Interstate Batteries supply house (not the retail store). The following web site indicates they supply them.

http://www.usbattery.com/usb_rv_p1.html

NOTE: I've not used this source but give it as an example of on line sources.

FWIW, it's unlikely that the batteries carried by high volume outlets like Walmart or auto supply stores will be true deep cycle.

Good luck.

JT KIrby

RCtime · 07-02-2009, 06:27 PM

OK, an update
I felt well enough today to complete this battery swap.
I purchased the 3, Sams club 12V deep cycles. I bought my extra batery cables at Camping World.
They charge 2.35 for the two copper end terminals and $5.50 a foot for the large #2 wire. Its actually welding wire that can be purchased at welding shops. You get your 10% discount if a memeber.
The tray was cruddy, so washed it out. Lifting those batteries in the tray was a chore, they are heavy.
I disconnected the 4 1/2 foot negative terminal wire that goes to ground, and replaced it with a 6 foot negative ground wire. I did this so I could run the positive/negative terminals from opposite ends of the battery bank. (read Skigramps/ Steve's input from above and the link.)
The common metal plate that 3 ground wires ran to, and the end teminal for my negative battery wire slightly rusty so I cleaned it up. and attatched the new negative battery wire.
I held my breath and attatched the last connection to the battery. No response from the battery pack which was good. ran inside the coach and turned on the coach disconnect switch, the panel readout was 12.5.
Climbed up the back ladder of the coach and removed the cover over the solar panel, inside the little red solar charger diode lit up, so I guess I am ready to go.
I want to thank everyone who contributed to my battery replacement

wa8yxm · 07-03-2009, 10:08 AM

One thing you failed to mention was how BIG those 12 volt batteries are.. The most common six volt battery is 232 amp hours, a pair of Group 29 will have around 210 amp hours (Basically the same) a pair of Group 31 will hit about 250, note I'm comparing pairs to pairs. add in the 3rd 12 volt and you add 50 percent more.

Of course if you have say 8-d's.. Well each of those is about the same as a pair of Golf Car batteries

Source: Interstate battery specification charts

The moral: Without knowing what size 12 volt batteries you have, (And for that matter what size sixes, there are larger six volt) all I can say is..... In this post

RCtime · 07-03-2009, 10:28 AM

Quote:

Originally Posted by RCtime

Perfect, thanks Steve. I just got back from Sams club and am going with their 12V deep cycle RV Marine battery. $68.75 apiece. plus your trade in.
215 amp. hr.. I have to get an extra set of cables for the 3rd. battery
They are group 27 battery.
Your cables look heavy duty, so I will take one of mine along with me when I get them. I guess a good auto parts store.

here ya go Wa8yxm