House Batteries

[john_harris]

We have a 2007 HR Endeavor with original 4-6v interstate batteries dated '06.

When MH was new we had issue with inverter which resulted in batteries dropping voltage frequently but after dealer fixed inverter, voltage would remain above 12v over night with moderate load.

We store motorhome indoors with connection to shore power so charge is maintained when not in use. On one occasion, I let water levels get low, but generally the have been monitored and topped of regularly.

When traveling we are dry camping approx 60% of the time so batteries do get a workout. On recent trip voltage drop a little more excessive so I figure we have gotten about as much life out of them as we should expect. I have recently noticed two of the batteries have a slight bulge and the power cables seem to be swollen at the terminals with a turquoise paste like substance around the insulation.

I plan to replace batteries and cables, but should I be looking at anything else? What should be normal voltage drop overnite after having batteries charged to absorb levels with minimal (parasitic loads only)? Since we had problems from start, I am not sure what to expect out on new batteries.

Any feedback would be appreciated.

[wolfe10]

John,

Bulging batteries indicates a problem. Generally, this is an indication that they have been overcharged. That MAY indicate a problem with the charger (or inverter/charger) but could also be an indication of a weak or dead cell. A 12 VDC battery (whether a 12 VDC battery or two 6 VDC batteries wired in series) has 6 two volt cells. If one cell is dead, your charger will charge at the same voltage. Clearly, charging 5 cells at the same voltage as 6 will result in severe overcharging of the remaining good cells and is a common cause of battery swelling.

A fully charged 12 VDC battery at rest (no charging and no discharging) is 12.7 VDC. A 50% discharged battery is 12.2 VDC. Discharging below 50% materially shortens battery life.

Given your description of age and bulging, I would replace all batteries.

Brett

[desertdeals69]

The swollen cables is the corrosion buildup, not a good thing.

When you replace everything put a protective coating of some sort on the terminals.

I prefer a spray that has a red tint to it and seals out the oxygen and prevents corrosion.

[theoldman]

The swollen cables is the corrosion buildup, not a good thing.

When you replace everything put a protective coating of some sort on the terminals.

I prefer a spray that has a red tint to it and seals out the oxygen and prevents corrosion.

Had that on mine when I got it.

Qustion is what is it and where to get it?

[hermanmullins]

Oldman,

Look at your cables. There are numbers on them. They are most likely 2/0 cables. You can purchase cable at your local welding supply store.

They also have the lugs you require.

They will be less there then any place else but will still be expensive.

Herman

[andyshane]

I'm more of a student here than instructor; but, two of us who own Class A motorhomes just traversed the Pacific, arguing this one. My Monaco-owner captain swears that the house batteries have to be removed from recharging for the duration of storage, to maximize battery life.

'Gotta admit, my Trojans' terminals go Chia Pet and need to be cleaned regularly; I replenish water every two months.

The downside: the microwave clock needs to be reset, every time I "power-up."

Anyone else do this?

[desertdeals69]

Had that on mine when I got it.

Qustion is what is it and where to get it?

CRC Battery cleaner #06023 and Battery terminal protector #06046

Should be available at major autoparts stores.

[QuiGonJohn]

Is there a link to a good guide for the best maintenance practices of deep cycle batteries, including not only water level, but useage, discharging and charging practices, etc.?

[desertdeals69]

Interstate batteries used to have a booklet that explained the care of golf cart batteries. I don't know if its still availble.

[David33]

Post show that there are some problem with charger because charger is the source for getting electric storage. You need to check charger not battery. Also battery contain plates of silicon who change positive in negative.

[wolfe10]

Post show that there are some problem with charger because charger is the source for getting electric storage. You need to check charger not battery. Also battery contain plates of silicon who change positive in negative.

David,

Yes, the charger could be a problem. But, one dead cell in a battery will cause the same symptoms. A perfectly functioning charger will try to charge 5 cells (5 good ones and one dead one) at the proper charge voltage for 6 cells. That WAY overcharges the 5 good ones.

That is why you never combine old batteries with new ones. If the old one dies, the result is way overcharging the good one(s).

[RVerOnTheMove]

I am going to be replacing my 4 current Lifeline 8D batteries but I don't want to pay that much for new batteries. I see there is a new AGM battery out there from Universal Battery at about 1/2 the cost of a Lifeline. Does anyone know anything about this battery or company (I'm OK with it being built outside the US)?

Additionally, I am trying to figure out the actual advantage of using 1-8D battery over using a couple of 6-V golf cart batteries to create one 12V. The 8D is listed as 255 AH and I have seen regular wet cell golf cart batteries with rating in the 300+ range. Help, please.

[Koliver]

8-D and Golf Cart designations are just size, as are "group", 4-D, etc.

8-D, being roughly 2x the size of GC, means you need the help of someone young and strong to move them. If your battery bay was designed for 8-Ds, you will likely need extensive modifications to switch to GC. Where differences come in is if you compare wet cell technology to AGM or what have you.

You need to stay with one technology for all of your batteries that are connected to a single charging source.

If $ is important, the cheapest way to store amperage is still the old, low tech, wet cell, in whatever size fits your battery bay.