Battery Question

[jenna55123]

Hello we just got a fifth wheel trailer I think its a 1993 Aljo Skyline its been plugged into shore power since new it was my grandfathers he gave to us since it needs quite a bit of work. Anyways the batteries are dead dead and we need new. We have heard of people getting the same ones, but my husband works as a diesel mechanic and can get those batteries and my dad has a friend who can get us a big cat battery which weighs 100 lbs and you only need one or two diesel type, we have been told to go with the cat it will still be 12 volt and has a deep cycle, a friend used one and said it runs amazingly we have close to the same trailer, my parents have a newer one which is prob 1008 or above they have the reg batterys and they work just fine. What do you guys think would be best, the diesel we may be able to get close to free and same with Cat. Thanks in advance

 

[denmarc]

This topic is a wide open subject.  You are going to have to ask yourself what you expect out of the 5'ver depending on the type of camping you and your family are planning on using the RV for.

More info is needed.  Are you planning on traveling with it?  Any added weight could pose a problem. 

If parked, a whole different answer would be in order.  Tell the forum what you have in mind and more direct answers should follow.

 

[Mopar1973Man]

It all about the Amp Hour capacity.

I can't really speak on the standard deep cycle or the golf cart batteries much. But I am solar/hydro power here at home with 410 Amp/Hr batteries in 2 bank giving 820 Amp/Hrs. So using amp meter or figuring Amps from Watts / Volts will give you the amps. Once you figure out how many amps your drawing you be able to figure out what size of battery fits your living style the best. Also bear in mind the weight of the batteries on the RV.

Like myself I got two standard Deep Cycle batteries and can make about one 24 hour span on a single charge. I typically pack a small genny (2Kw) for charging back up.

 

[Gary RV_Wizard]

Calling a battery a "diesel' or a "Cat" isn't descriptive enough to help make a decision.  You need to talk about battery capacity in AH (amp-hours) or RC (Reserve Capacity). Those are the standard means of measuring the ability of a battery to provide long term power (as opposed to cranking an engine).

Generally speaking, no battery designed for starting an engine will excel at long term power - you really want what is known as a "deep cycle"  battery for that. But seeing as though you may be able to get those other batteries cheaply, just pick the one with the greatest AH or RC rating. The CCA (cranking amp) rating is meaningless for trailer use, so ignore that.

 

[John From Detroit]

One thing about amp hours, or Reserve capacity or whatever you wish to call it (Reserve Capacity is not all that good a choice)

For any given battery size,, Say Group 29, the amp hour capacity difference between a starting battery (one extreme) and a true deep cycle (The other end) is often no more than 5 amp hours, in fact often it's zero.

What is different is the amount of that power you can use before you damage the battery.. (Deep cycles it's usually close to 50%,  Starting batteries do not like being run down that much) and how well they recover from an "OOPS".. What's an OOPS,, Way less than 50%. SOC.

I have, however, seen two different batteries of the same size, Same make, Different models, (Both Starting) with significantly different Reserve Capacities, Same amp hours, Different RC's.

 

[denmarc]

I'm going to take a stab at it.  Being a truck driver myself, I may know what the OP is pertaining to.
First of all, a "diesel" battery is nothing more than a starting battery.  Designed for a short term, high amperage draw to start diesel engines.  That is why on class 7 and 8 diesel trucks 2, 3, or 4 batteries are incorporated onto the truck depending on the accessories of that truck.  Not a good choice for a decent house battery.  Amp hour rating just isn't there.

The "Cat" battery is a heavy equipment battery.  Perhaps a group 4,6 or 8.  A better choice than the above mentioned.  But unless you know your amperage needs, still not a good choice for a house battery.  They are considered a starting/deep cycle battery.  Designed for heavy equipment left out in the field.  Those that need that extra push on those cold mornings to get that big diesel started with molasses for oil.  Not a good long term source of power.  Long term meaning a couple of hours.  I may be wrong, but I am guessing by your post these "almost free" batteries are used.  Take your chances.  You get what you pay for.

I have 4-Group 4's on my parked TT.  A lot of weight in just batteries.  This bank works for me.  But as I stated in my previous reply, depending on your use of the 5'ver, there are better options available I think you would be happier with in the long run.

 

[jenna55123]

Thank you all... I dont know what all the specs are on the batteries ill have to ask my hubby and dad. We will use the trailer as just for camping, a few times a year for now and usually only a weekend maybe once a year a week if we make it on that trip with everyone else, but the week one we may have shore power. Yes the batteries will be all but free thats why I was asking, but we want whats best for the use. I guess ill try and get the specs and maybe will be able to get better help. Thank you again.

 

[jenna55123]

Oh and I found out as we just got it last week and haven't moved it to our name till this week its a 1993 Aljo Skyline

 

[Phil Hyde]

Thank you all... I dont know what all the specs are on the batteries ill have to ask my hubby and dad. We will use the trailer as just for camping, a few times a year for now and usually only a weekend maybe once a year a week if we make it on that trip with everyone else, but the week one we may have shore power. Yes the batteries will be all but free thats why I was asking, but we want whats best for the use. I guess ill try and get the specs and maybe will be able to get better help. Thank you again.

As others have suggested, just make sure you get a "deep cycle" battery.  Also called a "marine" battery.  Many "marine" batteries are labeled "dual purpose" because in a boat application you do have to start an engine.  The RV application requires a true deep cycle design.  This is why many people switch to "golf cart" batteries.