House Batteries

Luv2journey · 01-09-2012, 09:32 PM

Hi Everyone Happy NewYear

On my Coach two of my three house batteries will not charge. I have one at 12v another at 10volts (this one drops right after I take the charger off it) and the last at 8 volts (will not charge at all). Being new to RV I assume that the latter two are dead. Can I just hookup one battery for now until the winter is over at that point I will buy two more?

Thanks in advance for your input

2003 Winnebago Journey DL 39ft , Cat 330

Cheers
Dennis

Rmiscoord · 01-09-2012, 10:02 PM

Should be Ok. The Batts are connected in parallel and you can have 1 or as many as you can safely store. I would monitor is closely for Charge and water though.

autofish · 01-10-2012, 12:19 AM

One battery will work fine just not a lot of reserve but ok for winter storage. How ever when you get to buy new batteries do not mix the old battery with the new ones as the old one will keep dragging the new ones down.

Dunner · 01-10-2012, 06:48 AM

If you don't have a 3 stage charger, get a BatterMinder® and keep an eye on water level. The fish is right. Budget for 3 new batteries, or 4 or 6 - 6v batteries if you have room. There is actually more current capacity in the 6v batteries. Sam's Club has a good price on some decent 6v golf cart batteries. <$80 each.

Stevegd007 · 01-10-2012, 10:37 AM

Yep...water level maintenance. Ya got to look at this at least every 1/2 of the year. If you using the battery heavily even more often. Non-sealed battery types seem to blow off lots of water.

Rmiscoord · 01-10-2012, 12:56 PM

While 6v batts are superior, if your coach is similar to mine, there is only room for 3 12v batts but 4 6v batts will just fit but will need custom made cables and may need structural modification to the cabinet because of the batt height. There is a thread on this forum where some folks have converted to 6v.

wa8yxm · 01-10-2012, 01:39 PM

I would say the 10 volt has at least one shorted cell, perhaps 2, and 3 on the six volt.

Disconnect those two, leave only the good battery connected, Group 29 (Maxx-29) Marine Deep cycle at Wall-mart, about 85 bucks a pop.

If you'd like a bit more capacity, GC-2's at Sam's club, (since these are six volt you put two in series and treat them like a single 12 volt) will give you 10% more capacity than two G-29s and cost about 20 bucks less. They are, however, the kind you have to water, where as the Maxx-29's are Maintenance free.

desertrv · 01-10-2012, 05:24 PM

I had a battery to go bad, wouldn't you know the one in the back, just as the temps dropped in the teens. I disconnected the 12v battery and I am currently using the two remaining 12v until I get ready for the spring. It would be nice if I could make 6v batteries work. Not for sure about the space.

oneydee · 01-11-2012, 07:43 AM

Quote:

Originally Posted by wa8yxm

I would say the 10 volt has at least one shorted cell, perhaps 2, and 3 on the six volt.

Disconnect those two, leave only the good battery connected, Group 29 (Maxx-29) Marine Deep cycle at Wall-mart, about 85 bucks a pop.

If you'd like a bit more capacity, GC-2's at Sam's club, (since these are six volt you put two in series and treat them like a single 12 volt) will give you 10% more capacity than two G-29s and cost about 20 bucks less. They are, however, the kind you have to water, where as the Maxx-29's are Maintenance free.

Just read somewhere that there is a difference between MARINE deep cycle and just deep cycle and the former is not for use in an RV. I will need to replace my two current 12V deep cycles this spring so I am in the market. Would value accurate information!

Dave78Chief · 01-11-2012, 09:26 AM

Can you use a Marine type battery in an RV? Yes. Many do (i.e the Walmart MAXX 27 or 29 Marine battery)

Is the overall effectiveness of a Marine style battery as good as a battery designed specifically for Deep Cycle operation? No. A deep Cycle battery is designed for long term lower amperage draw rather than short term high amperage draw for starting applications. The design of the plates in a Marine battery are a comprimise because it performs both starting and reserve capacity functions (a comprimise between starting and true deep cycle).

Here is a laymans explanation: Marine Battery Vs. Deep Cycle Battery | eHow.com

Typically, the length of life of a true deep cycle is longer than a Marine battery because of the heavier plate design. However, that length of life is directly dependent on how you care for the battery. In days gone by, I have killed a 12VDC starting battery in a riding lawnmower in one season because I did not understand the need to keep it charged over the winter months.

Dave

garym114 · 01-11-2012, 10:45 AM

The reason the batteries probably got to such a poor state is because they were allowed to drain completly under load or left for a long period of time in a partially discharged state.
Keep them charged to use 'em.

oneydee · 01-14-2012, 10:03 AM

Quote:

Originally Posted by Dave78Chief

Can you use a Marine type battery in an RV? Yes. Many do (i.e the Walmart MAXX 27 or 29 Marine battery)

Is the overall effectiveness of a Marine style battery as good as a battery designed specifically for Deep Cycle operation? No. A deep Cycle battery is designed for long term lower amperage draw rather than short term high amperage draw for starting applications. The design of the plates in a Marine battery are a comprimise because it performs both starting and reserve capacity functions (a comprimise between starting and true deep cycle).

Here is a laymans explanation: Marine Battery Vs. Deep Cycle Battery | eHow.com

Typically, the length of life of a true deep cycle is longer than a Marine battery because of the heavier plate design. However, that length of life is directly dependent on how you care for the battery. In days gone by, I have killed a 12VDC starting battery in a riding lawnmower in one season because I did not understand the need to keep it charged over the winter months.

Dave

Thanks (once again) Dave,

Everything I am reading is consistent with what you are saying. I am cutting and pasting a good article that I thought also shed some illumination on the topic:

Starting (sometimes called SLI, for starting, lighting, ignition) batteries are commonly used to start and run engines. Engine starters need a very large starting current for a very short time. Starting batteries have a large number of thin plates for maximum surface area. The plates are composed of a Lead "sponge", similar in appearance to a very fine foam sponge. This gives a very large surface area, but if deep cycled, this sponge will quickly be consumed and fall to the bottom of the cells. Automotive batteries will generally fail after 30-150 deep cycles if deep cycled, while they may last for thousands of cycles in normal starting use (2-5% discharge).
Deep cycle batteries are designed to be discharged down as much as 80% time after time, and have much thicker plates. The major difference between a true deep cycle battery and others is that the plates are SOLID Lead plates - not sponge. This gives less surface area, thus less "instant" power like starting batteries need. Although these an be cycled down to 20% charge, the best lifespan vs cost method is to keep the average cycle at about 50% discharge. Unfortunately, it is often impossible to tell what you are really buying in some of the discount stores or places that specialize in automotive batteries. The golf car battery is quite popular for small systems and RV's. The problem is that "golf car" refers to a size of battery (commonly called GC-2, or T-105), not the type or construction - so the quality and construction of a golf car battery can vary considerably - ranging from the cheap off brand with thin plates up the true deep cycle brands, such as Crown, Deka, Trojan, etc. In general, you get what you pay for.
Marine batteries are usually a "hybrid", and fall between the starting and deep-cycle batteries, though a few (Rolls-Surrette and Concorde, for example) are true deep cycle. In the hybrid, the plates may be composed of Lead sponge, but it is coarser and heavier than that used in starting batteries. It is often hard to tell what you are getting in a "marine" battery, but most are a hybrid. Starting batteries are usually rated at "CCA", or cold cranking amps, or "MCA", Marine cranking amps - the same as "CA". Any battery with the capacity shown in CA or MCA may or may not be a true deep-cycle battery. It is sometimes hard to tell, as the term deep cycle is often overused. CA and MCA ratings are at 32 degrees F, while CCA is at zero degree F. Unfortunately, the only positive way to tell with some batteries is to buy one and cut it open - not much of an option.