battery maintenance

[jfaberna]

Since I don't have electrical hookups where I store my Monty, I remove the battery and leave it in my garage at home. On doing that recently after having left the battery in the RV for a couple of months, it needed charging. So I hooked up my old trusty 3 way manual charger. I have a 2 amp trickle, 10 amp charge, and 50 amp start switch. I left the Interstate RV/Deep cycle 12V battery the dealer installed on trickle for 24 hours. When I first connected the charger the current read about 3 amps. After 24 hours, it read as close to zero as it gets unless unplugged completely. Not sure why it changed since it's not an automatic charger. Since the battery is only 6 months old, I assume the battery is fine and now fully charged. I won't know for sure until I reinstall it in the RV.

My goal is eventually to install a roof mounted solar charger that can be left hooked to the battery continuously. But until I overcome my fear of drilling holes in my roof, I'm looking for a automatic charger that I can use in my garage to leave hooked up to the RV battery all the time so I can grab the battery and go without having to remember to charge it the night before I need it.

So I looking for recommendations on such a charger. I will switch to 2 6V batteries in series when I change out my old battery at some point, so if they have a automatic charger that can handle 6V and 12V that would be great. These type of charges seem to be out there, but I don't know which are any good. BTW, can you charge 2 6V batteries connected in series with a 12V charger? I think the answer is yes, but not sure.

[bncinwv]

Since you have to unhook the battery to remove it from the rig, it would be a lot less work to just leave it int he rig unhooked. It will not drain, and when you are ready to use it just hook it back up. Even simpler is just to install a battery cut-off switch to complete isolate the battery when in storage (there are drains that still deplete the battery even when the on-board switch in the convenience center is disengaged. This is how I do it, and do not even have to remove the battery over the winter months. Just a thought and a lot easier on the back??
Bingo

[Carl n Susan]

quote:Originally posted by jfaberna



... when I change out my old battery at some point, so if they have a automatic charger that can handle 6V and 12V that would be great. These type of charges seem to be out there, but I don't know which are any good. BTW, can you charge 2 6V batteries connected in series with a 12V charger? I think the answer is yes, but not sure....

Just to be clear, the 6V batteries are wired in series to produce 12V. That is essentially the same as a 12V battery. The charger only sees 12V. You do not want nor need a 6V charger.

[jfaberna]

quote:Originally posted by bncinwv

Since you have to unhook the battery to remove it from the rig, it would be a lot less work to just leave it int he rig unhooked. It will not drain, and when you are ready to use it just hook it back up. Even simpler is just to install a battery cut-off switch to complete isolate the battery when in storage (there are drains that still deplete the battery even when the on-board switch in the convenience center is disengaged. This is how I do it, and do not even have to remove the battery over the winter months. Just a thought and a lot easier on the back??
Bingo

So a fully charged battery with the cables disconnected will remain charged for months? That would solve my current problem until I can get a solar charger. That might be what I should do with my car that we leave at home while camping.

[jfaberna]

quote:Originally posted by Carl n Susan

Just to be clear, the 6V batteries are wired in series to produce 12V. That is essentially the same as a 12V battery. The charger only sees 12V. You do not want nor need a 6V charger.

So with a 12V charger I have to hook them in series even in the garage. That makes sense, I just didn't know if there were any issues with the automatic controller thinking it is connected to a single 12v battery vs. 2 6V batteries in Series. As long as both batteries were of the same age and condition, probably not an issue??

[Phil P]

quote:Originally posted by jfaberna


So a fully charged battery with the cables disconnected will remain charged for months? That would solve my current problem until I can get a solar charger. That might be what I should do with my car that we leave at home while camping.

Hi

I am not sure what car you have but if it’s a GM read the manual. Here is a very specific procedure for disconnecting the battery or you will enable the emergency battery system in the OnStar and that is a $700 repair.

Phil P

[BB_TX]

If you are gone for long periods, forthe car left at home I would just get one of the small automatic battery maintainers to keep it charged while you are gone.

[psomers]

quote:Originally posted by Phil P

Hi

I am not sure what car you have but if it’s a GM read the manual. Here is a very specific procedure for disconnecting the battery or you will enable the emergency battery system in the OnStar and that is a $700 repair.

Phil P

Never heard that. I have a 2008 that has original batteries that will need replacing soon. Could you direct me to that caution? I guess pickups with OnStar would be affected.

[K0LCB]

I have a 1953 Ford I leave in storage all winter, usually 6 or 7 months. I always disconnect the battery. First battery lasted 7 years. It is 12 volt now

[jfaberna]

I've done a little more independent research on this. While disconnecting a battery completely will do a good job preserving the electrical charge, it will contribute to sulfation. I went looking for an automatic charger and found one that is designed to be continuously hooked up to the battery. It has a microprocessor controller that charges the battery slowly and then maintains the charge and cycles thru a sulfation test and desulfation cycle.

This seems like a good solution to my problem, so my battery is always ready to go when I go pick up the RV. It will also work for keeping my car charged while I'm out RVing for months.

[PatnRich]

I have a seven day timer and connect that to a battery charger for four hours once a week, to maintain the cars battery when traveling. Another option might be a solar powered trickle charger. A friend of ours had one for his class c and it worked well.

[kdeiss]

Purchase a Battery Tender connect it and forget it!
I have always removed battery and connect to a battery tender.have left cars connected for 5 6 months.

[Phil P]

quote:Originally posted by psomers
Never heard that. I have a 2008 that has original batteries that will need replacing soon. Could you direct me to that caution? I guess pickups with OnStar would be affected.

Hi

On our 2009 Silverado 3500 Duramax you have to let the truck sit for 45 minutes without opening a door or doing anything that will make the computers think you are preparing, or have operated the vehicle in the last 45 minutes. The 45 minutes maybe a little more than the book says but close enough.

A second procedure is to open the driver’s door and leave it open while you disconnect the batteries. I would recommend opening the door again before installing the batteries.

There are also instructions to disconnect the battery or provide some support for the batteries if the vehicle is to be stored more than 30 days.

For the Silverado there is instruction not to leave anything plugged into the auxiliary power plugs when the truck is parked for more than 24 hours. This causes the main computer to see what it thinks is an electrical system fault and it brings the other 4 computers on line periodically to check the system for some kind of fault. This will kill your batteries in 3 days; ask me how I know LOL

As for the location of these instructions I am not sure of because I purchase the repair manuals for the truck when it was new, they are 7 volumes and very extensive.

I am reasonable sure the caution about long term storage is in the owner’s manual.

I just purchased a new Malibu a few months ago and haven’t even looked at the owner’s manual yet.

I found out about all of this because after the dealer spent $700 of mine trying to get the OnStar working I sat down and read the manuals and by following the testing procedures in them found one battery with a bad cell was causing the OnStar problem and the AM radio problem.

Here is a link to a NAPA battery charger I have been using for many years. It will not over charge your batteries and works very well.

http://www.napaonline.com/Catalog/Ca...315_0006389653

Phil P

[jfaberna]

quote:Originally posted by kdeiss

Purchase a Battery Tender connect it and forget it!
I have always removed battery and connect to a battery tender.have left cars connected for 5 6 months.

Yeap, I got a BatteryMINDer(r) model 1500 from Northern Tool. Seems to be just what I need.