Dead Battery -- how to charge

nachtmsk

Senior Member
Joined
Jan 3, 2014
Posts
239
Location
Palmyra
Hi,
So, my RV has been sitting in the driveway for a while and I noticed the other day when I tried to turn on the lights, they wouldn't turn on.
I checked the battery with a multi-meter and it comes up at .5 volts.
I've never charged an RV battery before so I have a few questions.
First question, can I use the "Battery Tender Jr" to charge an RV battery? I have the BT Jr. for my motorcycle battery.

Robot Check

I looked up the steps online. Any comments advice on these steps?
1. Clean terminals with baking soda/water
2. Petroleum Jelly (Vaseline I guess) on terminals
3. Check water level, fill with distilled water if needed
4. Connect charger.

Should I leave the charger on it all the time so it doesn't die again?
Thanks!
BTW -- the battery is the original I got with the camper about 18 mos ago.
mike
 

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Hi,
So, my RV has been sitting in the driveway for a while and I noticed the other day when I tried to turn on the lights, they wouldn't turn on.
I checked the battery with a multi-meter and it comes up at .5 volts.
I've never charged an RV battery before so I have a few questions.
First question, can I use the "Battery Tender Jr" to charge an RV battery? I have the BT Jr. for my motorcycle battery

Robot Check

I looked up the steps online. Any comments advice on these steps?
1. Clean terminals with baking soda/water
2. Petroleum Jelly (Vaseline I guess) on terminals
3. Check water level, fill with distilled water if needed
4. Connect charger.

Should I leave the charger on it all the time so it doesn't die again?
Thanks!
BTW -- the battery is the original I got with the camper about 18 mos ago.
mike

This what I would do.
Check the water level and fill if needed.
Use a regular charger to get it up to full charge first.
After it's up to full charge, check each cell with a hydrometer to see if there is a dead/bad cell.

Be very careful using baking soda to clean things. If you get any in the cells it will kill the battery. Baking soda neutralizes battery acid, inside or out.
I would use Dielectric grease on the terminals and connectors.
If the battery takes charge and the cells test out OK, then hook up the battery minder and leave it on all the time. If it is the battery minder you have it will de sulfate the batty if it's left on.
Just remember, it has to be plugged in to a circuit that works 24/7 other wise it will kill the battery again.
 
Thanks LLoyd.

When you say "a regular charger", what do you mean specifically. The Battery Tender JR. I have isn't a regular charger?
No idea what a hydrometer or what it means to desulfate a battery but I will look them up.
mike
 
Thanks LLoyd.

When you say "a regular charger", what do you mean specifically. The Battery Tender JR. I have isn't a regular charger?
No idea what a hydrometer or what it means to desulfate a battery but I will look them up.
mike

This a battery minder with desulfator

http://www.amazon.com/BatteryMINDer...r=8-1&keywords=battery+tender+plus+desulfator

Regular charger puts out more amps then a battery minder. You can get many different sizes.
http://www.amazon.com/Schumacher-SC...id=1454807811&sr=8-4&keywords=battery+charger

http://www.amazon.com/Schumacher-SC...id=1454807811&sr=8-4&keywords=battery+charger
 
If you have a neighbor that has a charger , borrow it and have him help you hook it up. That way you will learn . A 10 amp charger will top it up , then your tender (probably 1 amp) will keep it up . You probably do not have a battery disconnect and the propane detector and stereo memory will wear the battery down in a few weeks.
 
So if something puts out more amps that just means it will charge it faster? Can I just get the battery minder or do I need both products?
Thanks,
M

Yes more amps means it will charge faster, but a big charger is not something you want to leave hooked up to the battery for ever either.
harley made a good point about seeing if there is one in the neighborhood to borrow.
 
Thanks guys. Nope, no neighbor here that does that kind of stuff. That's why I'm asking all of the questions. Want to make sure I do it right and don't
1. Ruin my battery
2. Blow it up or set it on fire
3. Zap myself
Particularly concerned about #2 and 3!
 
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You can pick a very inexpensive one at Harbor Freight tools that will be just fine, I've had one for years & it still does the occasional charging job. As said above do not leave it hooked up forever, use your battery tender for that.
 
Battery tenders can be found almost anywhere. I've got two Schumacher automatic tenders that I picked up from Wally World for about $26 each over the past couple of years. Use them for the lawn tractor, motorcycle, RVs, and almost anything else that has a battery.

The tender will fully charge a depleted battery in less than a day then keep it charged.
 
Battery tenders can be found almost anywhere. I've got two Schumacher automatic tenders that I picked up from Wally World for about $26 each over the past couple of years. Use them for the lawn tractor, motorcycle, RVs, and almost anything else that has a battery.

The tender will fully charge a depleted battery in less than a day then keep it charged.


A battery tender/minder will not fully charge a depleted battery in that short of a time period. It's impossible because they don't put out enough amps.
 
A battery tender/minder will not fully charge a depleted battery in that short of a time period. It's impossible because they don't put out enough amps.

The Schumachers have a rapid charge function then a tender function. So it's not impossible because I just did it this week to my motorcycle battery.
 
What is the rated charging amps on your Schumachers?

The reason I stated it's impossible to charge a dead battery in one day is the fact that the battery minder plus only puts out 1 & 1/2 amps.
That is why it's called a maintainer, not a charger. It also keeps the battery desulfated, if it is allowed stay connected when the rig is not in use.
 
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1.5 amp in the tender mode. No idea about the charging mode since it an automatic function controlled by the computer chip inside the charger.

I've frequently used this for charging a depleted battery. In fact, I don't even own a battery "charger". I used these "maintainers" and it charges dead batteries very nicely. That said, I normally don't use them on RV batteries as I've never had the need to do that.

However, I have a friend with the same maintainer and he uses it on his 12v deep cycle boat batteries. He's never had a problem either pulling out a spare battery, charging it for a couple of hours, then running around the bay with that battery in his boat.

And at this point, I'm out. Time to go tend the smoker and get ready for the Super Bowl. :)
 
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I have the Schumacher speed charger. It puts out 10,6,or 2 amps.
I also have the battery minder plus which puts out 1 & 1/2 amps. It's also
(like the name implys) a battery minder.
I hook it up to my two 6V Trojans in the fall and it stays on them all winter. It conditions, desulfates, and maintains the batteries without any worry of over charging.

My Schumacher shuts off when the batteries reach the charge state and doesn't turn back on automatically. Nor does it desulfate.



I did some further checking and I see Schumacher has come out with a new model since I purchased mine. Looks like a big improvement.
BUT, they still say nothing about having a desulfation mode.

http://www.amazon.com/Schumacher-SE...808&sr=8-2&keywords=schumaker+battery+charger
 
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When I had my cruiser, and left it sit for an extended period, i would disconnect the battery.
therefore, the propane detecter, etc. would not wear the battery down.
 

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