Latest thinking on new battery

Bravada

Senior Member
Joined
Jul 1, 2017
Messages
144
Location
Adrian, Mi.
New Owner and in desperate need of a new battery. What is the current thinking? Group 24, 27, 31 single or dual. Flooded or AGM. Brand???

I am not interested in modding the battery box. Last battery I purchased ( for my previous rig)was a group 31 which replaced a group 27 and that replaced a group 24 that came with the trailer new. The 24 was minimal at best.

First question will a group 31 fit in the box? ( they are a little taller than a 27)

Will two 27 fit?


Down the road I am planning on adding solar.

Thanks in advance.
 
I would guess it would depend on your battery location. mine being a 1980 only had a regular plastic battery box from like walmart attached to the frame behind the propane tanks so it's whatever will fit inside of it. w.o doing any mods.

I seen later models that had the battery mounted lower and has a cover over it.
 
I suspect the largest battery that MAY fit is Group 27. My trailer will only take Group 24 however, but I was able to install two of them in parallel for double the capacity.

Measure your battery box carefully to see what will go in there. IF you can get two in, do it and install the largest battery that will fit.

The only kind of battery I'd consider would be a "deep cycle/marine" FLOODED type. Look for one with the highest Amp Hour capacity you can find. No battery really likes being deep cycled though, so try to keep the charge at or above 75%. If you pay extra for AGM or the other "fancy" ones, you're just throwing money away in my opinion. They really will not last any longer and can cost up to twice as much.

I buy my batteries at Costco, because they have good power ratings, a reasonable warranty, no hassle return policy and are sold at a good price.

If you DO move ahead with your plans to install solar, please look at the thread I posted on my solar installation: http://www.hilotrailerforum.com/f28/my-new-200-watt-solar-installation-4354/ It's now a 300 Watt installation because I added a third panel between the two that I originally installed. There was room for it and it was easy to connect it in series with the other two. On my last trip, in full sun, I measured 14.5 Amps charging current right after driving and setting up camp. Again, the tape is holding perfectly and I've never used my generator since installing the panels.

- Jack
 
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I have a 2001 Tow Lite 26TFB. The battery box is on the tongue behind twin propane tanks between and level with the top of the frame rails. It does appear that two group 27s will fit. I haven't done any measurements yet and would like to fit twin 31's. ( I think it's wishful thinking).

With the new battery chemistry and advancements it makes sense to review these options. Looking into Interstate's ECL Professional group 24 and 27. It is discontinued now so at best if I found a pair they probably be old stock.
 
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I went with two 24's for fit. My local Rural King has the AGM for the same price as flooded elsewhere and I used to constantly check the batts fluid levels. Now I don't worry as much. Second reason for fit is I remember reading a long time ago about an owner leaving something on the cover, lowered the top and shorted the batt causing a fire, I think. With these two batts installed, I had enough room to place 3" Styrofoam block so my diamond plate won't short. Also notice on the side of one batt is my Battery Minder. Keeps me fully charged with NO damage to the batts.
Inside I have a small dehydrator, here in Fla this time of year we have a LOT of humidity. I used to used this pure water to top off the Batts, now I use that water for the flowers!
Tree
 

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" I remember reading a long time ago about an owner leaving something on the cover, lowered the top and shorted the batt causing a fire, I think. With these two batts installed, I had enough room to place 3" Styrofoam block so my diamond plate won't short. "

That may of been me, Tree. :)

That said- I have read that the AGM batteries require a bit lower voltage than standard wet cell batteries for the initial charge. Something like 14.4 volts for wet and 14.1 for AGM and gel cells. However, even my standard batteries, according to the same source, should be getting better than 14 for the appropriate gassing to take place and re-charge and I never see more than about 13.6 on my volt meter when hooked up to the converter. Thus- I suspect I haven't been doing my batteries any favors the last couple of years charging them with the standard converter/charger on my 2001 hi-lo. I have considered replacing it....... but haven't felt like springing for the extra dollars. maybe i will when these peter out.

Rick
 
My BatteryMinder battery maintainer has different settings for the different kinds of batteries. It also has temperature compensation.

I've covered ALL of the battery posts and connectors with non-conductive covers. Never have to worry about shorts in there.

- Jack
 
RE: the 1999 21 footer I bought 10 almost 2 weeks ago- I have the same "battery box is on the tongue behind twin propane tanks between and level with the top of the frame rails. It does appear that two group 27s will fit" that Bravada describes. Presently there's a single older Autocraft Gold 65-2 1000 a cranking and 150A reserve capacity. Not even a deep cycle battery. It's charging and holding about 1`2.4 V, but I'll want to be replacing it soon. I'm interested in hearing how the dual batteries work out.
PROBLEM- The plastic batter box is cracked and needs to be repaired before a heavier or maybe even the present battery will falls through. What should I use to repair the battery box cracks?
 
My battery box has a metal strap underneath to help support the battery weight. You could always add that. I personally would not trust just a cracked plastic repair job.

As far as batteries go, you don't care about "cranking Amps". That's the very high, short duration current draw needed to turn a vehicle engine against compression. What you want to maximize is Reserve Capacity (RC) or Amp Hour (AH) ratings. Two identical batteries wired in parallel effectively double the RC or AH of one. There have been other links to battery facts - Here's one I just found: https://www.batterystuff.com/kb/articles/battery-articles/battery-basics.html

If you DO use two batteries in parallel, it's important that they be as IDENTICAL as possible. That means the same brand, same group size, same type and, the same date of manufacture. (The fresher, the better).

And again, NO battery likes to be "deep cycled". Try to keep your battery(s) at or near full charge at all times.

- Jack
 
If I were to repair the cracks in my batterey box (and I should) ----I would use fiberglass tape and a good epoxy ( west systems) to do it. Mostly I would try that because I am used to working with the stuff. It would be important to clean the plastic very well and rough it up with with sand paper- and then I would likely make the repair using progressively wider strips on top of each other.

Rick
 
Thanks Jack and Rick for ideas. I cleaned the battery terminals with baking soda and water and applied petroleum jelly to the cleaned terminals. I think some of the acidic gunk from the battery terminal fell on the plastic and ate away some of it where the drain hole is. I've cleaned up the battery box and added some temporary reinforcement for the battery which is on the other side opposite the drain hole and crack. I think its OK, but will do some permanent reinforcement later when I go to two batteries. The battery is a group 65 battery over 2 years old which is probably OK for the present. The Dometic model 600315.321 fridge draws 15 A on 12V which is by far the greatest drain on the battery and means I can't keep it on much except when hooked up to 120V power using converter. The fridge is a 3-way, but AC is 240 volts (a European model???) so basically worthless unless I buy a 2:1 transformer to change 120V to 240V. I won't be using propane any time soon as the rig came with just a single empty propane tank.
 
But, Doug - a 20# propane container only costs about $15 to fill. And, new tanks are not very expensive either. Maybe about $20-24 at a place like Home Depot, Costco or Walmart.

The refrigerator runs best on propane, and a single tank will last a long time. I use propane to heat my hot water and run the refrigerator. A tank will last me around two weeks, maybe longer.

- Jack
 
I second Jack on this. My refrigerator runs terrific on propane and I tend to go a whole season on two tanks. By the way- I'm not sure what a group 65 batterey is but it sounds like a standard auto batterey. If you cannot afford two at this time- I would look at getting a single deep cycle batterey. I think that will work better for you. When we camp, in summer, unless I need the air conditioning for the dog (very old dog) I prefer non-electric sights ( if I'm going to have time at home to recharge the battery) and use batttery operated lanterns inside and the propane for cooking and refrig. If I'm being particularly miserly I may use a smokey Joe grill along with a Dutch oven for cooking outside. Just some thoughts.

Rick
 
Thanks Jack and Rick,
Yes the group 65 is a standard auto battery. It seems to work well enough, so replacing it is not high on the priority list right now. Inspecting the top and resealing where necessary, getting the water pump to work, and greasing the guide, pulleys, and cables come first. I did the latter this afternoon, first venture under the Hi Lo. Everything looked OK to my untutored eye except a cable going to the front driver's side is rubbing against and into the fresh water tank and hot water tank. Didn't determine if its the regular cable or the manual lift cable so need to go under again. Maybe I can get some photos.
I have many other questions, concerns, and fears so think I'll start a new thread on those!
 
Doug

To the best of my knowledge there is no "manual lift cable." That feature is just a way of bypassing the electronics on the hydraulic pump by using a small lever in a slot and pumping it by hand. My guess what you see is your regular lift cable on that corner.

Rick
 
Returned from time in San Francisco area with family, now I can start on the HiLo.
Bought a group 31 home with the understanding that if it is too tall I could return it. I had to take the pledge the if returned for a group 27 it would be in the same condition when it left.
Well the 31 fit just fine. To my surprise I though I was replacing a group 27. It was a 29! A group 29 is a small/ less powerful group 31! Yet bigger than a 27.
A 29 is a dual purpose battery. It is built for both starting and for deep cycle use. It gives up some ability in one area for the ability to handle another task.

What do you loose? Cold cranking amps. Now what are we going to do with amps that are not going to be used? Nothing..... I want all my amps lined up on the side of reserve capacity.

Fit, like I said it fits in my 2001 26TFB battery box just fine. The actual height difference between the group 29 and the 31 is about 1/8" higher.

Note, there is no interference between the metal top of the battery box and the positive cable has a cover for the clamp and post. Without measuring I would guess there is approximately a 1/2" of clearance. For an additional piece of insurance I added plastic taped to the bottom of the battery cover. This was procured from one of the many reusable grocery bags rummaging in the trunk of the grocery getter. It was the perfect size and fit beautifully. Held in place by some trusty duct tape. Please don't tell the DW.
 

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The Cold Cranking Amps (CCA) is just a measure of how much current it can deliver in a short time under very high draw. No, you are not using it, but a starting battery has thinner plates and cannot stand up to deep discharges as well as a marine/deep cycle battery.

But, if you don't let the battery drop too low before being recharged, it's a moot point. Congratulations on fitting a Group 31 battery in there! That WILL give you more capacity than a Group 29. And your insulation solution looks good too. I put vinyl tubing over the screw posts on mine, which sticks up a bit above the posts, keeping them away from the metal top. AND, I installed clamp covers, like the one on your positive battery post, over all my cable clamps.

Your installation looks very neat!

- Jack
 
Making repairs

Try Gorilla Duct tape. It is premium strong. Sold at Walmart. They even have a small one that is good to have in the HiLo.
 

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