Battery maintainer charges to 14+ volts
- Thread starter loneryder
- Start date
Post the specific brand and model number of the maintainer and how you are using it.
I would be OK with it as long as it wasn't an application where it was on all the time.
What make/model and how long have you been monitoring it, "keep(s)ing them there"?
If the voltage is no longer rising then I'd measure current. More than a few tens of mA is going to cook off too much electrolyte if used for long. May be harder to measure if pulsing, would need a logging meter if not 'scope.
If the voltage is no longer rising then I'd measure current. More than a few tens of mA is going to cook off too much electrolyte if used for long. May be harder to measure if pulsing, would need a logging meter if not 'scope.
If left connected indefinitely then it's harmful. How sophisticated a maintainer is it ? You would normally expect the voltage of a smart charger to drop once the battery reaches full charge.
Battery maintainers burn up batteries. Don't leave it on all the time.
Thats an overgeneralized statement that is not true.
I haven't used any battery maintainers, but it sounds like it's simulating a running alternator. Older cars used to sustain 14.1-14.8v consistently before they started electronically controlling alternators to lower voltage. I get why they lower voltage on newer vehicles, but on short tripped vehicles this is why there's a danger of running the battery low. I kept having hard starts on my wife's Ford Edge with a new battery until I disconnected the battery sensor so it operated like an older car.
I don't think you'll have an issue using it. You can't charge a battery without having a higher voltage than it has.
I don't think you'll have an issue using it. You can't charge a battery without having a higher voltage than it has.
I would at least cycle it occasionally so it's not being constantly bombarded, but it should not hurt the battery.
gathermewool
Site Donor 2023
My alternator on both cars puts out around 14.2VDC. My smart chargers bulk charge at higher then taper down as the battery charge completes and then switches to a float charge.
When I manually charge my batteries I use 14.4VDC for my flooded batteries, then 13.5 or so float. The current when full is in the hundreds position, usually; depends on internal resistance.
When I manually charge my batteries I use 14.4VDC for my flooded batteries, then 13.5 or so float. The current when full is in the hundreds position, usually; depends on internal resistance.
This maintainer charges at different levels depending on state of charge in battery. It starts at 12v then quickly lowers voltage charge as the battery state of charge improves. It's on my Mercedes which is basically off the road for winter. If I open the door, lights come on and the charger will start charging at about 8 volts and lower charge rate rapidly as the door lights didn't use that much battery. It's really sensitive.
What if it automatically shuts off.. some maintainers do that. Just because its charging at 14.4v doesn't mean it stays like that 24/7.
This thread is basically worthless without knowing the model of battery maintainer.
Somehow I doubt that its charging at 12v because the battery should be higher than 12v.. and not sure what you mean by charging at 8v.. that would be discharging?
And your first post said it charges at 14v and stays there..
Can we get some clairification? Doesn't make sense currently.
Sorry I meant it charges and maintains the battery at 14.2v. As you can see in the pic, it's connected and is off. So it doesn't stay on. When I opened the door and the lights came on, the maintainer came on, charges back to 14.2v and turns off.
It should not damage the battery. Otherwise, people who drove their vehicles continuously (at 14+ volts) would dry up their electrolyte. It wouldn’t hurt to check the cells more frequently with a higher float voltage though.
Then burn up some batteries and learn the same way I did...
My riding mower battery has been connected to a $10 Harbor Freight maintainer/trickle charger pretty much continuously for years now.
It's from August 2017. Still started the mower just fine as of about a month ago.
It’s a blanket statement, certainly not borne out by my experiences. For 25 or 30 years I’ve been using battery tenders of several makes on my batteries whenever the car or motorcycle was parked overnight or longer. My batteries are lasting 6-11 years. I don’t think that qualifies as premature demise.
I’m not doubting you had some batteries “burn up”. There might be many reasons for that happening. Blaming the use of battery tenders wholesale doesn’t explain why many / most peole using them have no issues. Maybe the battery tender(s) you are using just malfunctioned.
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That's exactly it. It's likely doing what the battery needs. If it sustains 14.4v I'd either shut it off occasionally or question the condition of the battery.
