Upgrade to 2 batteries...........

[Bamabox]

Background info first. 2017 XLite 21RBS. Came with one battery in a plastic case on the cross mount area of the tongue. Upon close inspection, the case is just held down with a cheap strap and can slide and jiggle around a bit while going down the road. My bad for not addressing this earlier, this our 3rd season. Come to think of it, addressing it now in the 3rd season is pretty good for me :rolleyes:. My normal would probly be about 5. We rarely dry camp, but are considering doing more of it. Sooooooo, that leads me to your suggestions. I have no desire to get involved in 6V golf cart batteries. Seems like overkill for what my needs are. So I’m thinking 2 really good low maintenance true deep cycle 12V’s with lots of ampere hour ratings, in parallel, in one nice case that holds both in the stock location on the tongue rack.

Who you got? Both batteries and case. Thanks.

[Bamabox]

Forgot to add, trailer stays plugged in to 15A cord at home and throughout the winter, so batteries stay charged.

[Canonman]

22545Bama,
I definitely think you are on the right track. We're using a pretty standard group 24 "deep cycle" battery that came with the Cougar at purchase. 4th season and still working well.
When we replace these, we'll be going to a group 27. A little larger, more amp-hour and will still fit in our existing battery boxes. I have not seen a single battery box that can hold both batteries. Probably out there but not a big deal for us.
With LED lights in the new TT's and judicious use of the other accessories, you can expect 2 to 3 nights on well charged batteries. You might want to look into a battery charging system, either an inverter type generator or solar to keep the batteries charged for any extended dry camping.
As for battery brand, my pocketbook is the big delimiter. I plan to go to Costco or Sams and buy our replacements. Consumer reports likes Duracell and I can get those at the big box as well as Interstate. I don't plan to upgrade to AGM type batteries not just because of cost but they may not be compatible with the converter in our Cougar. Hope this helps. Good luck with your search:)

[Steveo57]

I have a 22RBS and went with two 6 volt batteries.

[Bamabox]

I have a 22RBS and went with two 6 volt batteries.

Good looking setup. Never really thought much about people stealing my battery. Raggies are everywhere I guess. Looks like you have an Anderson like I do. I like mine but have never had anything else so no frame of reference. Have you had other types and if so how would you compare the Anderson?

[JRTJH]

You can certainly find "true deep cycle 12 VDC batteries" but they typically cost significantly more than "6 volt golf cart batteries".

Buying "marine/RV deep cycle batteries" is NOT buying a "true deep cycle battery". If the battery has "CCA" listed on the label, it's a "HYBRID" battery with thinner plates and is designed to deliver high amperage to start an engine (and also provides a sustained low level output for RV use)...

As always, no product can be "good at everything".....

A "Car battery" has very thin plates and is designed to provide a "HIGH BURST" to start an engine. But won't survive repeated deep discharge without failure.

A "marine/RV battery" has "slightly thicker plates with holes drilled in them (or a stamped mesh" surface) to increase the surface area" to obtain that "burst power" while having thicker plates that don't warp as easy as automotive batteries, but still can't survive repeated deep discharge without failure, but won't fail quite as fast...

True Deep Cycle batteries have fewer plates, but they are thicker and not as much surface area (they don't need to provide "BURSTS" of power) so the plates are less subject to warping and collecting hydrogen bubbles (which cause corrosion/sulfation which damages the plates rapidly. That means they can survive repeated deep discharges without failure. In other words, they are more "durable and reliable" in an RV environment.

While you can buy 12 volt deep cycle batteries, typically they'll cost much more than golf cart batteries. So essentially, if you're looking to increase the available storage capacity, you can equip your trailer with two "high priced 12 volt batteries or you can accomplish essentially the same thing with two golf cart batteries, usually for around half the price.

Don't get me wrong. You can certainly buy a single deep cycle 12 volt battery and improve your dry camping experience. You can buy two to further improve your dry camping time. Those batteries will usually cost around $175-200 each. With selective (wise) shopping, you can get almost the same energy storage capacity with two 6 VDC GC2 batteries, usually available at Sam's or COSTCO for less than $100 each.

If you're going to go to a "two battery system" the issue isn't "fighting a 6 volt system", it's having more than one battery on the tongue. Whether it's two 6 volt ones or two 12 volt ones, that hassle is exactly the same.

[Bamabox]

If you're going to go to a "two battery system" the issue isn't "fighting a 6 volt system", it's having more than one battery on the tongue. Whether it's two 6 volt ones or two 12 volt ones, that hassle is exactly the same.

Is there a “hassle” with having two batteries on the tongue that I am not aware of?

[JRTJH]

Is there a “hassle” with having two batteries on the tongue that I am not aware of?

In your initial post you said, "I have no desire to get involved in 6V golf cart batteries."

Essentially, having two 6V golf cart batteries on the tongue is no more "maintenance" (hassle) or "work" (hassle) than having two 12V batteries on the tongue. That leaves 12V golf cart (or other true deep cycle) batteries as the option. Typically, 12V deep cycle batteries cost twice as much as the GC2 6V version but really offer no advantage other than the capacity of operating on one battery. That's "negated" by wanting two batteries for extended camping.

[sourdough]

Here is a link to Trojan 12v deep cycle batteries.

https://www.trojanbattery.com/markets/mr/12v/

There are several different kinds. I think if you back up to the main page you can find their 6V batteries as well. When replacing keep in mind the physical limitations of the space you have to put them, if any. On mine, 2 group 24 batteries fill the built in bracket to the edges, the extra length of a 27 won't fit. I am also limited by height because the batteries are enclosed back behind a cowl and the LP tanks and have very limited access space. 2 6v might fit but I've not done any in depth research because I just don't need them. We dry camp very seldom.

[Steveo57]

Good looking setup. Never really thought much about people stealing my battery. Raggies are everywhere I guess. Looks like you have an Anderson like I do. I like mine but have never had anything else so no frame of reference. Have you had other types and if so how would you compare the Anderson?

For a few bucks I figured it will keep the batteries from walking. I also locked up the propane tanks for the same reason.

I went with the Anderson hitch solely because of the weight. My back can't handle dragging the heavy head of the other hitches and getting them unhooked and hooked up by myself anymore.

It does the job for me. I've had several other wdh over the years and they all worked well. Many miles without an issue.

[Logan X]

I know you said you weren’t interested in the 6v batteries...

I thought I would share anyway. Below is a link to the box I used. I also keep mine locked up, I’ve had a battery stolen before.

https://no.co/hm426

[UB1]

We have the same setup as Steveo57 with two Trojan T105 batteries.Century plastics makes a box for two GC2 batteries end to end for about $60 and can be found on allbatterysalesandservice,as well as ebay.I purchased a Camco dual GC2 box on Amazon for $18,I haven't installed it yet so I can't speak to how well they fit.I will say that the box is kinda flimsy similar to most standard battery boxes.If you're considering an upgrade I would suggest you consider going to two 6 volt GC2 batteries it made a big difference for us dry camping.

[GMcKenzie]

I guess the question is why the aversion to 2 6 volts?

[MarkEHansen]

I agree. If you're going to have 2 batteries (or 4, for that matter) anyway, you can get more bang for the buck using 6v batteries.

[Bamabox]

Well, this is why forums are so good. Lots of great info and starting to convince me to go 2 6V.

[Bamabox]

I know you said you weren’t interested in the 6v batteries...

I thought I would share anyway. Below is a link to the box I used. I also keep mine locked up, I’ve had a battery stolen before.

https://no.co/hm426

Nice setup. That battery box looks like it is much wider than the rails on the tongue. How did you secure it?

[Logan X]

Nice setup. That battery box looks like it is much wider than the rails on the tongue. How did you secure it?

I used a 2x10 piece of pressure treated lumber and ripped it down to 8 inches to fit snugly in the rails. I screwed the lumber to the rails and then screwed the box onto the lumber using wide washers. It is very secure. I have towed 1000 miles with this set up. The small box next to it houses the shunt for my battery monitor.

[bbells]

Batteries plus sells 12v golf cart batteries that are up to 200 amp hours, if you don't want to do the 6v gc batteries. FYI, marine deep cycle batteries are not deep cycle batteries. Most are only about 60ah when new. If a 12v battery has cca on it or weighs less than 100 pounds it most likely isn't deep cycle.

[pdaniel]

Nothing other than added tongue weight, and, as a reminder, don't wire the batteries in series.

[Bamabox]

OK, got my Costco Interstate GC2’s couple days ago, got individual GC2 boxes, everything fit fine on the tongue rack. They are in, and wired. Each battery checked at 6.36V prior to installing. After install and jumpered in series, voltage checked at 12.72V. Love it when math works. After reconnecting the battery breaker, and connecting my 110/15A “shore power” from the barn, batteries were reading 13.41. Here’s the question. While I’m connected to my shore power, is the built in converter/inverter in my 2017 Cougar XLite 21RBS going to maintain a “proper” charge level on these GC2’s? And not OVERCHARGE them?

[Canonman]

The converter will see the new set up as a single 12v battery and charge normally. It will charge slower since the batteries are larger but that's about the only change.

[Bamabox]

So no worries about overcharging when constantly hooked to 110 shore power?

[Logan X]

OK, got my Costco Interstate GC2’s couple days ago, got individual GC2 boxes, everything fit fine on the tongue rack. They are in, and wired. Each battery checked at 6.36V prior to installing. After install and jumpered in series, voltage checked at 12.72V. Love it when math works. After reconnecting the battery breaker, and connecting my 110/15A “shore power” from the barn, batteries were reading 13.41. Here’s the question. While I’m connected to my shore power, is the built in converter/inverter in my 2017 Cougar XLite 21RBS going to maintain a “proper” charge level on these GC2’s? And not OVERCHARGE them?

Unless I’m mistaken, the onboard charger/converter sees your 2 GC2 batteries the same as 1 12v battery. Your battery set up is still flooded lead acid with 12v output. The charging profile is the same.

[JRTJH]

OK, got my Costco Interstate GC2’s couple days ago, got individual GC2 boxes, everything fit fine on the tongue rack. They are in, and wired. Each battery checked at 6.36V prior to installing. After install and jumpered in series, voltage checked at 12.72V. Love it when math works. After reconnecting the battery breaker, and connecting my 110/15A “shore power” from the barn, batteries were reading 13.41. Here’s the question. While I’m connected to my shore power, is the built in converter/inverter in my 2017 Cougar XLite 21RBS going to maintain a “proper” charge level on these GC2’s? And not OVERCHARGE them?

First, the "built in converter/inverter" is a "converter/charger" and there's no "inverter" that's built in as OEM equipment. CONVERTERS change 120VAC to 12VDC and are used to charge batteries. INVERTERS change 12VDC to 120VAC and are used to discharge batteries...

That said, IF (NOTE THE CAPS and underlined word) your OEM WFCO converter/charger is operating properly and the reverse polarity fuses are intact, then it should reliably charge and maintain your GC2 batteries without any problems. You WILL need to check battery electrolyte level regularly. When I first installed my GC2 system, I checked the batteries weekly until I was sure they weren't leaking or losing electrolyte. After a couple of months, I felt comfortable with them and now (for the past 6 years) I check them monthly when the trailer is in use and store them in the garage during the winter. While in storage, I do not "maintain them on a charger" but rather I connect them monthly to an automatic 12 amp battery charger and leave them connected overnight (usually about 12 hours). Otherwise, my GC2 system has required no maintenance or special handling.

You might want to buy a battery handling strap to lift the batteries in and out of the battery boxes. They are an excellent addition to any golf cart battery system. The first time you "crush a finger" lifting a battery by the sides of the case, you'll appreciate the handling strap. https://www.amazon.com/3G-Golf-Battery-Strap-Yamaha/dp/B0172FSJAI/ref=sr_1_3?crid=1IUTVQMMW6NEV&keywords=golf+cart+battery+strap+carrier&qid=1562517914&s=gateway&sprefix=golf+cart+battery+strap%2Caps%2C174&sr=8-3

[Gizmo2]

I have owned multiple RVs and boats with both dual 12v and 6 volt battery configurations. Two 12v batteries in parallel can suffer from loss of capacity as the stronger battery will discharge thru the weaker until they are the same voltage. This isn't much of an issue when they are new but can be as the batteries age. With dual 6 volts in series one weak cell will have a fraction of the effect on the total bank voltage as 12s in parallel.

I also completely agree with what's been posted about the cycle life of 12v vs 6v. To get good cycle life from a 12v you should really consider AGM batteries. They are twice the price or more however.

One issue with golf cart batteries is that they consume water over time and you have to top them up periodically with pure water. I think 6v is worse than 12 because of the way they are vented. I've noticed the 12 v batteries on my boat were low on water after a year of use so the maintenance free claim is just a marketing slogan.

I worked on a project involving a battery powered refrigerated shipping container a couple of years ago. The original system used 4 six volt AGM batteries in series that could keep the system cold for 5 days. I modified it to use LiFePo lithium batteries. It's was amazing what a difference they made. The system had double the capacity at half the weight. I know there are golf carts using this technology along with a few RVs. It will be a game changer if the price ever becomes competitive.

[Ccsluke]

Just do the math!
Two 6v 100ah batteries series’d Together gives you 12v at 100ah. So expect to pay much more for one 12v 100ah battery. You’ll get the same output from the one 12v as two 6v’s. In my research (don’t take my word, do your own), One 12v battery is cheaper than two 6v when you compare total ah output. As an electrical engineer I’ve dealt with all types of batteries in various applications for the past 40 years. IMO I would never put a 6v battery on my RV!

[Canonman]

Depending on the model converter in your Cougar, you should have 3 charge stages. Our Cougar is equipped with the WFCO 8955 converter.
Bulk, 14.4 vdc; Absorption, 13.6vdc and Float, 13.2vdc. The float function is meant to maintain your batteries while the other two are for bringing the batteries up to full charge.
The 8955 is capable of monitoring the battery load and automatically adjusts from absorption to float mode. If there is any load detected while in float mode the converter will switch back to absorption mode.

[Logan X]

Just do the math!
Two 6v 100ah batteries series’d Together gives you 12v at 100ah. So expect to pay much more for one 12v 100ah battery. You’ll get the same output from the one 12v as two 6v’s. In my research (don’t take my word, do your own), One 12v battery is cheaper than two 6v when you compare total ah output. As an electrical engineer I’ve dealt with all types of batteries in various applications for the past 40 years. IMO I would never put a 6v battery on my RV!

...except one of my 6v batteries is 240 amp hours. I haven’t seen a single 12v battery that can match that.

[Ccsluke]

Again, if you compare ah to ah, I can also get two 12v 150 ah batteries for about the same price as two 6v 240 ah batteries. You have to series the 6v’s to get 12v at 240ah. If you parallel the two 12v’s you’ll get 12v at 300ah...and if one of my batteries goes bad, I can just disconnect it and still have 150ah capacity. This is not an opinion, it’s fact. Again, I see absolutely no use for 6v batteries on an RV!

[MarkEHansen]

Just do the math!
Two 6v 100ah batteries series’d Together gives you 12v at 100ah. So expect to pay much more for one 12v 100ah battery. You’ll get the same output from the one 12v as two 6v’s. In my research (don’t take my word, do your own), One 12v battery is cheaper than two 6v when you compare total ah output. As an electrical engineer I’ve dealt with all types of batteries in various applications for the past 40 years. IMO I would never put a 6v battery on my RV!

Okay, here's my math. Regarding FLA batteries only, the best Bang-for-the-buck 12V battery I could find was the Trojan SC S225. This can be had for a little over $200 and has a 20-hour capacity of 130AH.

A reasonable 6V battery is the Interstate GC2 which can be had from Costco for around $100. This has a 20-hour rate of 210AH.

Dual 12v batteries means 260AH for around $400.

Dual 6v batteries means 210AH for around $200

In my opinion, the clear winner is the 6v set. Not only better AH per dollar, but you get other benefits from 6V batteries, such as heavier plates, better discharge levels, longer life, etc.

If you're looking for more AH capacity, you can go with the Duracell SLI6V225S 6v battery. It has a 20-hour rating of 250AH but cost around $200. Using two of these, you would get 250AH for around $400. Not quite as good as the Trojan, but you still get all the other 6v benefits.

I still think 6v batteries win, easily.

[Logan X]

Again, if you compare ah to ah, I can also get two 12v 150 ah batteries for about the same price as two 6v 240 ah batteries. You have to series the 6v’s to get 12v at 240ah. If you parallel the two 12v’s you’ll get 12v at 300ah...and if one of my batteries goes bad, I can just disconnect it and still have 150ah capacity. This is not an opinion, it’s fact. Again, I see absolutely no use for 6v batteries on an RV!

Could you share a link to the 12v 150 amp hour battery please?

[Bamabox]

Could you share a link to the 12v 150 amp hour battery please?

I might be a bad searcher on the internet, but when I was deciding on the battery upgrade issue, I did a LOT of searching and I don’t recall a 12V true deep cycle (no cold cranking spec) with 150 AH @20 hours.

[Bamabox]

http://i.imgur.com/LKpp85Z.jpg

Well, the 6V’s are in. Happy except for the batter straps. Tough to get really tight. Maybe they’re tight enough, but if I have to keep an eye on water level in the batteries I’d like to come up with something better and easier. They fit OK on the tongue rack, but not much room to spare from side to side with the individual boxes. If I had used a single box to hold both, would have needed to reroute the propane line. This was it just went in between the two boxes. Thanks to all for the advise and help.

[Canonman]

A FINE JOB...Finally Done!!

[Ccsluke]

Can’t vouch for your internet search skills one way or another. I provided facts backed up by science. you provided an opinion which you are certainly entitled to! I guess it’s just what you feel the most comfortable with. That’s why I only try to post science based facts and let the readers make up their own minds and form their own opinions.

[JRTJH]

Gil,

Have you considered changing out those battery box straps for cheap 1.5" ratchet cargo straps? You can get them at WalMart for around $5 each. Just thread them up, ratchet them tight and tuck the loose end under the strap. When you need access, loosen the ratchet slightly, slide off the side of the box and open the lid. Easy to keep track of since they don't ever leave the battery tray and "finger tight on the ratchet handle" is all the strength needed to keep them tight.

[Bamabox]

Yes, there are lots of opinions about 6v vs 12v on a trailer. And your facts might be based on hard science. Just provide us with the brand and a link to the 12V 150AH @ 20 hour battery. That would be a fact as well.

[Bamabox]

Gil,

Have you considered changing out those battery box straps for cheap 1.5" ratchet cargo straps? You can get them at WalMart for around $5 each. Just thread them up, ratchet them tight and tuck the loose end under the strap. When you need access, loosen the ratchet slightly, slide off the side of the box and open the lid. Easy to keep track of since they don't ever leave the battery tray and "finger tight on the ratchet handle" is all the strength needed to keep them tight.

Done. Thanks.

[Logan X]

Can’t vouch for your internet search skills one way or another. I provided facts backed up by science. you provided an opinion which you are certainly entitled to! I guess it’s just what you feel the most comfortable with. That’s why I only try to post science based facts and let the readers make up their own minds and form their own opinions.

You said that you could get a 150amp hour 12v battery for the same price as a 240 amp hour 6v battery. Can you provide a link to a specific battery or name the specific battery? I would be interested in that when I need new batteries.

[WestCoastWanderer]

Looks good!

I don't think I could get those 6V batteries into the tray on my 2018 21RBSWE.

I have installed a second battery into the rack. Interstates, because I love the warrantee. Of note, I had to trim the back off of the plastic battery box covers in order for them to fit. It's too tight against the front of the trailer. I get two nights of dry camping without drawing down the batteries too much. By then, I want full hookups, and away I go.

Of note, I drilled several holes into the bottom of the battery boxes to drain any rain/road spray that accumulates (another tip from this forum).

[UB1]

Trojan makes 12v 130 amp hr batteries but they msrp @ $245 each.I got my Trojan T105 6v batteries for $130 each and Costco and Sams club are surely cheaper than that.

[JRTJH]

Sam's Club price for Duracell GC2 (215-20amp/hr) is $89.88
https://www.samsclub.com/p/duracell-golf-car-battery-group-size-gc2/prod3590228?xid=plp_product_1_1

COSTCO price for Interstate GC2 (210-20amp/hr) is $98.99
https://www.costco.com/Interstate-6-Volt-Golf-Cart-Battery.product.100476406.html

Both carry a 12 month "free replacement" warranty.

Core Charge is $15 per battery in Michigan, but changes based on the state of purchase.

[Mainer]

Two 12 volt batteries have twice as many holes to watch for low electrolyte as two 6 volt batteries.:whistling: That makes twice as much work.

One cautionary note: Unless the batteries are exactly matched one may charge slightly different, not a problem with parallel connection, but can be with series connection if not "Equalized" and may cause problems over time. RV converters don't normally have an "Equalize" stage. I pull mine every winter and charge them individually with a 6 volt charger to avoid any problem.

[Bamabox]

Two 12 volt batteries have twice as many holes to watch for low electrolyte as two 6 volt batteries.:whistling: That makes twice as much work.

One cautionary note: Unless the batteries are exactly matched one may charge slightly different, not a problem with parallel connection, but can be with series connection if not "Equalized" and may cause problems over time. RV converters don't normally have an "Equalize" stage. I pull mine every winter and charge them individually with a 6 volt charger to avoid any problem.

Thanks. Good advise. I should invest in a 6V charger.

[Scott902]

Maybe a stupid question, but can you use a 12v charger to charge two 6v batteries?

[MarkEHansen]

Maybe a stupid question, but can you use a 12v charger to charge two 6v batteries?


Yes. When the batteries are wired in series, they present as a single, high-capacity 12v battery.