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Old 11-21-2009, 05:40 AM   #1
Join Date: Jan 2009
Location: Pennsylvania
Posts: 73
SUN #766
Battery MinderPlus


I just got my Battery MinderPlus, and read the instructions.

I am pretty sure some have mentioned that they use this model.

The instructions tell you to keep it on the charger any time the battery is out of the camper and not being used.

I will not be using the camper/battery for about 4 to 5 months now.

Do they really mean it is OK for this period of time?

Or is it better to just use a regular battery charger, for maybe once a month to bring the battery up to charge?

How safe is this to use in the basement of my house? I already had a charger on a battery in the garage, and when I went out to check it, it had bubbled over and made quite a mess. Any chance of a fire starting?

Do you take the caps off or leave them on? Most chargers tell you to check the instructions with the battery, but I have never bought a battery that came with instructions.


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Old 11-21-2009, 08:10 AM   #2
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Join Date: Nov 2006
Location: Ohio
Posts: 10,516
SUN #89
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Hi Phil

Iíll pass along what I know about these as I have 5 of them. Yes, 5.

Check the electrolyte level, make sure each cell is topped off.
Fully charge the battery if it is not already. If it is slightly down then that is OK.
Hook up the Battery Minder Plus and leave it on all the time.

The Battery Minder Plus is a slow charger and can only give approx 1.3 amps when on full charge if you have Model: 12117. That is why you want to charge the battery with a normal charger if it has been unused for a long time or you just came off of boondocking and your battery is Ĺ way down.

Now the good part of what the Battery Minder Plus does is once you hit 100% full charge, it tapers off the current down into milliamps, like about 5 ma when the battery no longer needs more charge. That then creates the float voltage and current to keep the battery at peak charge but not over do it.

The desulfate circuit then kicks in after enough time has elapsed. And it can take days worth pending how bad the build up was to dissolve off the sulfate crystals if you never desulfated before.

The key to being able to leave these on all the time is the current drops off to only the natural bleed area a battery looses just sitting there doing nothing.

Think of it this way, a deep cycle battery, or lead acid battery is either discharging or charging. There is nothing else in the middle. Even when doing nothing there is a slight discharge going on. The Battery Minder Plus keeps a voltage present to stop the natural drain and limits the current to not do harm. And it has the pulse method of desulfating.

So yes, due to these features you can leave them on all the time. A standard float charger, like a Battery Tender, they are good too but they do not have the desulfation mode which is a drawback.

Since we camp all year round, I have mine in a plastic box under the camper and then plug in the battery. Iíll pop a pic later this weekend and post. This prevents the battery from discharging down to where the electrolyte turns more water and then can freeze the battery. I even plug it in during the summer. The other 4 I have are on my other batteries over the winter, the tractor, the lawn mower, the other camper stored in side, the truck but only do them over the winter other then the other camper inside, itís on all the time.

If you do not have a Battery Minder Plus, then yes, take the battery out, store inside off the concrete, top off with water, fully charge it and come back every month to month and a half and recharge. This does nothing for the heavy sulfate buildup, but it keeps the battery from draining down in discharge too low. And if you are not going to use the camper in the winter even if you have the Battery Minder, you can pull the battery out and put it on the unit in the garage.

Hope this helps


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Old 11-21-2009, 08:17 AM   #3
Join Date: Jan 2009
Location: Pennsylvania
Posts: 73
SUN #766
Thanks John,

I edited my post above with a few more questions, if anybody cares to look at those.

Going down now to plug the unit in.

Thanks again,
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