Swapping OEM batts for real Deep Cycle: Weight!

[SCVJeff]

I'm still looking at various deep cycle batteries to possibly upgrade and gain significant capacity to the coach. The problem is, I think that the Kwikee battery shelf is rated for 200 lbs. With the stock Interstate GP29's, my current weight load is 183lb. The smallest 6V upgrade I can do is 4ea. T-105 Trojans that weigh in @ 248lb. In poking around, there are some really sweet 6V batteries that will fit nicely into the tray that will supply anywhere from 894-1060A total RC current. The killer is the additional weight on the shelf. I'm not concerned at all about the extra weight in the rear since it's around 80-90b. But that's a 50% increase in the present load on the shelf.

As mentioned above, I was on the Kwikee site trying to match the dimensions to a size in their product line (can't find an exact match), but it looks like they're all rated at 200lb for aprox. size match. For liability purposes I kinda need to pay attention to the ratings (and I suspect this is a really conservative rating), BUT.... Has anyone gone through this and how did you deal with it?

Tnx, Jeff

 

[SCVJeff]

I'm still looking at various deep cycle batteries to possibly upgrade and gain significant capacity to the coach. The problem is, I think that the Kwikee battery shelf is rated for 200 lbs. With the stock Interstate GP29's, my current weight load is 183lb. The smallest 6V upgrade I can do is 4ea. T-105 Trojans that weigh in @ 248lb. In poking around, there are some really sweet 6V batteries that will fit nicely into the tray that will supply anywhere from 894-1060A total RC current. The killer is the additional weight on the shelf. I'm not concerned at all about the extra weight in the rear since it's around 80-90b. But that's a 50% increase in the present load on the shelf.

As mentioned above, I was on the Kwikee site trying to match the dimensions to a size in their product line (can't find an exact match), but it looks like they're all rated at 200lb for aprox. size match. For liability purposes I kinda need to pay attention to the ratings (and I suspect this is a really conservative rating), BUT.... Has anyone gone through this and how did you deal with it?

Tnx, Jeff

 

[skigramp]

We have a 2004 Journey ... my battery tray does not have enough vertical clearance for T-105 Trojans

Did you find a "deeper" tray?

 

[John Canfield]

Jeff - I'd try to talk with Kwikee directly and find out from them what the rating is. Then you can decide based on that info.

 

[BryanL-WO]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">possibly upgrade and gain significant capacity to the coach </div></BLOCKQUOTE>

not likely feasible, especially being so close to the max weight capability.

You might be able to gain some minor energy capacity by finding a battery that has higher cost and a lower lifespan rating.

Looking at http://lemley.net/electric/trojan.html I see that watt hours per lb runs between about 22 - 24 for typical RV batteries (T105, T125, SCS 200) - that's about 0.2% of capacity difference in weight energy density or about 12% for a typical battery. Of that, you'd only have half of it usable.

So, you either need to change your lifestyle to be more 'green' or to put up some (a lot) of solar or to make more frequent use of the genset or add some more batteries somewhere else if you don't have enough energy capacity in your battery bank.

 

[SCVJeff]

Thanks John. I'll call Kwikee, but may have to start with Winnebago because I can't find this tray on any of their cut sheets. It may be an OEM. However it happens, it's gonna happen in this space, even if I have it reinforced or custom made. I just have no reasonable space near-by to use, unlike my neighbor with his Meridian-36 who was able to weld a mount dead center unnderneath the chassis. The 34 just doesn't have that space..

Bryan: Thanks for the link! I had a full cut sheet for Interstate, but only separates for Trojan

 

[John Canfield]

Yeah - I like the idea of solar for those that boondock enough to make the investment worthwhile. My brother-in-law just had three 100 watt panels installed to the roof of his new Dutch Star (and of course the requisite controller, new wiring, etc.) Lots of $$$

Jeff - another thought if you really want more ampere-hours, you could stick a couple of sealed AGM batteries almost anywhere and even put them on their side or upside down. I would use a battery switch and not try to parallel them to your present house bank.

I think this is a case where you can throw money at the problem and accomplish some or all of your objectives.

 

[SCVJeff]

And with all this extra storage, I can justify at least one additional panel..

 

[SargeW]

I have toyed with that idea too Jeff. Let us know how it winds up.........

 

[jimandsue60]

I don't know if it is the same battery rack but I replaced the 3 batteries with 4 6 volt lifeline AGM's. The rack appears to be holding up fine.

Jim

 

[SCVJeff]

Thanks Jim.. Yep, it's the same shelf. I talked to Winnebago today about the loading concern, and the guy I talked to admitted he has worked with several folks on 6V conversions, but none had brought up the weight issue before today (leave it to me..). I have some part#'s I need to cross-reference, then call Kwikee, but he seems to think that Winne buys the rails, front lock and rolls their own. Since this is so deep, it may be built with the larger rollers on a much narrower sled. I'll try and talk to a human at Kwikee again tomorrow. Not an easy thing it appears.
BTW- What kind of a difference in longevity do you see between the GP29's and the 6V'ers? What's the Cap of your Freedoms?

Oh yeah!!... Anyone priced a battery lately? Make sure you're sitting down. Increases from 50-100% over some recent web prices. Looks like lead is turning into a precious metal. Who'da thunk?

 

[Bob/Becky D - VA]

Jeff:

Got my LifeLine AGM batteries at:

http://www.bdbatteries.com/marinebatteries.php

Was cheaper than the local dealers and Batteries+. Free shipping and no tax. Might be cheaper places, but I didn't find them. AGM batteries are non-hazardous and therefore can be shipped USPS, FEDEX, or UPS. Took 48 hrs to get mine. AGMs are pricy, but I think worth it for many reasons. I replaced my two lead-acid GP29's with two GP31s.

Bob D

Hopes this helps.

 

[SCVJeff]

Update on my project:
I am still waiting for the folks at Kwikee to pull their shop drawings on their OEM slide unit for Winnebago. Administration is in Oregon and Engineering is back east somewhere. I pretty much got the same response from the tech rep that I did from Winnebago, that this is the 1st time someone has called trying to verify loading vs. just piling batteries on. I left a follow-up call today and will call again on Tuesday if no reaponse.

Anyway, there has been a major upswing in the price of deep cycle batteries, and maybe across the board. Not sure.

Trojan and Interstate have seen as much as a 100% increase in price in the past few months

. I had my heart set on T-125's, but the $87 price I found on the web jumped to somewhere around $135 when I actually called, with a 10% increase slated next month, and no apologies. Another place was $167ea. Even higher elsewhere.

Same for the U2200's. The best price I found was around $115 +$27 core charge at the batteries only store in Santa Clarita. CW has them for $99ea. and charged me $87ea. (didn't ask why), So I'm smilin'. The battery shop says that this is going to get ugly cuz China is buying up all the raw lead. Used batteries are becoming quite a commodity these days.

So if anyone is procrastinating on a battery they know they need to replace, now might be a good time. Just a heads-up.

 

[KE0M]

Jeff - I replaced my 4 OEM trojan 12 volt batteries with 4 T-125 Trojan 6 volt batteries. I'll admit there is minimal clearance and checking the level of electrolyte is a PIA. For the rear pair, I can check the electrolyte with a dental mirror and add water with a meat marinating syringe, but I've found it easier, although a little more time consuming, to disconnect the front two, remove them, and slide the back pair forward. Then reverse the process and it's good to go. Sorry I don't have a pix handy.

BTW, before the switch, I completely sanded both battery trays down to clean, bare metal. Then after a couple of coats of metal primer, I coated both trays with Rhino lining. NO more rust there.

The hardest part of the switch was trying to find 3 stove bolts 7/16 X 10" because 1/2" stove bolts rub against the batteries on both sides.

I never considered the weight difference between the T 105 and T 125. I guess I traded weight for vastly increased reserve capacity. I've got more 12 volts than I know what to do with.

Good luck and best regards,
Larry

 

[SCVJeff]

Larry: You had FOUR house batteries? My neighbor has a 36' Meridian and his tray fits only 3. Same as mine.

 

[KE0M]

Oops! Jeff, you're right...you caught my error. Yup, I had only 3 12 volt house batteries and replaced them with 4 Trojan T-125 6 volt batteries. Now if I can only remember where I put the keys to my motorhome...

73's
Larry

 

[SCVJeff]

Larry: Keys are in the left jacket pocket. It's hanging in the downstairs closet..

Final Update:

I received a call from Kwikee this morning regarding the design load of the top tray. They say that this tray is rated at 250lb.

I feel a whole lot better missing this mark by 2lb. rather than 52b.

The next big trick will be securing them. Even though this is a deep tray and I seriously doubt that these batteries will hop up enough to short out without totaling the coach, I'd still like to do it. Using flooded cells makes bracketing a little more challenging with all those holes in the middle.

The other thing I don't like is having to terminate multiple cables (Inverter/ charger, solar, house B+, chassis grounds, temp sensors, etc.) across studs, and struggle to get them all on. I think the solution is to install a pair buss bar termination blocks external to the tray. Then all I need is 2ea. jumpers from the battery bank to the blocks, and the various solar and charger sensors stay tied to the battery studs.

I just need to take out a loan for a pair of 4' 2/0 copper jumpers (ouch!)

 

[Harry B-THOR]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">I just need to take out a loan for a pair of 4' 2/0 copper jumpers (ouch!) </div></BLOCKQUOTE>

Jeff,

I just did some cable mods to my battery tray and obtained the new 2/0 cables form a welding shop. My original cables were marked welding cables, so that gave me the clue. The even installed the new connectors for me at no charge. If I remember correctly I paid about $28 to recable for 6v batteries. This was about 6 months ago. But perhaps the Chinese are also buying all the available copper now

 

[BattChief-WO]

Larry,

Can you post a pic of how you arranged the T125's in your tray? I've got the same tray and was thinking of doing the same thing, but just don't see how 4 will fit. Anything you can send would help!