Electrical: Battery tender

[nibbs53]

Good morning. I have a question on battery tenders. I just charged the batteries on my 62 GT, and my 65 f 85. Took about three days each. Then I took my battery charger to the shop, I thought I'd charge all of the batteries at the shop. After an hour or so decided to check, it seemed like the battery tender was getting a little hot, is that normal. Could not really tell, with the cars at home, because the charger had turned off and cooled down. Unpluged the battery tender and put on a 3 app charger, no problem it did not even get warm.

Thanks for any help.

Patrick.

p.s. Where did that icon come from, the one in front of battery tender. I did not put it there.

Patrick.

[Gunslinger]

It sounds like an internal breaker might have tripped for whatever reason. Most battery tenders charge a battery to between 80%-100% of full charge then it cycles off until needed again, rather than run full time. They will get warm but shouldn't get hot. Their amperage is low enough to not get hot. A full blown high amp battery charger can get hot, but a tender shouldn't.

If you have the paperwork for your tender check and see what it might say. If you don't have the paperwork, see if the manufacturer has a website you can reference for that information.

[RadioRoy]

Be wary when using battery tenders. I put one on my 50 Commander for the winter and it cooked the battery drier than a potato chip. You have to keep an eye on them, even though they are generally sold for use as long time storage.

[Gunslinger]

I have a bettery tender on both Avantis and my Corvette all winter and have never had an issue. Keeping the batteries at a steady full charge should serve to lengthen the lifespan of each battery. All the batteries are the sealed type which may make a difference.

[Skip Lackie]

I agree with both RadioRoy and Gunslinger. In many years of use, my battery tenders have never damaged or overcharged sealed 12v batteries, but HAVE boiled away all the water in the commonly available (non-sealed) 6v batteries.

[over50]

There are a lot of different opinions and experience with battery tenders. I have battery disconnect switches on my cars that may sit long periods of time. I've never had a problem with them sitting for months then starting right up when I turn the switch on. An advantage of the switch is that you can easilly turn it off and work on the vehicle without having to worry about anything being energized. Of course, none of my vehicles have electronic radios or other things that need the voltage to maintain memory.

[Gunslinger]

I think part of using a battery tender is to get one that has circuitry that won't allow overcharging. Some of the cheaper models are really nothing more than a full-time trickle charger with a different name. Keeping an eye on them is a good thing as well to prevent potential problems in case of some malfunction.

[showbizkid]

I got tired of running the battery dead on my Pontiac, so I put a cheap $4.99 Harbor Freight trickle tender on it. That was a year ago. No adverse reactions; car cranks and fires immediately every time.

[Lark289]

It's funny but I can leave the battery on my Lark hooked up and let it sit for months during the winter months and it will crank right up. I have never put a battery tender on it and in over 12 years of ownership I am on my second battery. I also have an old Lincoln, but that I must disconnect the battery or it will go dead after a week or less. For this car I have a quick disconnect on the battery of the Lincoln and I simply let the battery sit disconnected for months and I can start the car right up with it. No battery tender on the Lincoln either, and I go through a battery every 5 or 6 years with that car too.

I have considered a battery tender for my late model car, a BMW 3 series (well, that is over 12 years old too!) when I let it sit because that car has a bunch of electronics that should be kept working. I have let that car sit for up to a couple of months, with the battery hooked up, without a battery tenter, without a problem, but I would not want to let it sit much longer than that. So, I don't know how much I really NEED a battery tender as I seem to be getting by without one, and for many years I have 5 older vehicles (now between 13 and 54 years old) I am able to get from 5 to 7 years out of each battery.

A couple of years ago I did buy one of those backup jumper batteries from Sears. I keep it plugged into the wall and in the event that I need it, it is ready to go. I have had to use it a couple of times and it has been handy. It also has a digital readout that tells me the charge state of the battery in voltage. When I hook it up to a battery in the car it gives me the voltage. When I crank the ignition I can watch the voltage drop (sort of like a load test). I can also read the voltage once the engine starts and see what volatage the alternator is putting out. This has become a great testing device that has allowed me to diagnose a bad starter motor on one vehicle. All in all my favorite new tool from two years ago.

[brian6373]

Unless you have a sealed battrey, the best test of a battrey is the use of a hydrometer. It will not only tell the state of chage, but will also check for a bad cell. A low reading of the battery for those of you who live where there are freezing winters run the risk of the battrey freezing. A battery that is charged and discharged will not last as long as one that is maintained at a full charge because of sulfation, or lead oxide that builds up on the plates in the cells. This prevents the lead plate from contacting the acid in the cell which reduces the chemical reaction that makes the voltage. Where I live we don't have "hard freezes" even if it might dip below freezing at night. But my Lark does have a factory clock that does put a current draw on the battrey with the engine stopped. I puchased a solar battrey maintainer from the good folks at H.F. , but I haven't got around to hooking it up yet. Going for a drive every week or two seems to do the job.

[nibbs53]

It sounds like an internal breaker might have tripped for whatever reason. Most battery tenders charge a battery to between 80%-100% of full charge then it cycles off until needed again, rather than run full time. They will get warm but shouldn't get hot. Their amperage is low enough to not get hot. A full blown high amp battery charger can get hot, but a tender shouldn't.

If you have the paperwork for your tender check and see what it might say. If you don't have the paperwork, see if the manufacturer has a website you can reference for that information.

[Warren Webb]

I got my Battery Tender (brand) thru the museum a couple years ago. I've never left it on for a whole season but have had it on for 3-4 weeks with no problems. I would contact the manufacturer first to make sure yours isnt defective. The last thing you need is a fire! Sears sells one they call a battery maintainer that often goes on sale around thanksgiving for around $20.00

[shifter4]

I have 2 BatteryTenders , one for the race car , and one for a Cub Cadet. I've
had no difficulties .
I preferred to buy that brand because they are made locally here in Volusia County.

http://batterytender.com/

[Paul Keller]

Am also using a "cheapo" Harb. Frt. batt tender - It only puts out 3/4 amp, barely what the resistance is in the elect circuit and battery itself - It definitely is safe. Anything w/ more power would be best if it were self regulating (stop charging when the batt. is up to charge). What the long term use would be I don't know (as to if it would keep a batt chaged over the winter).
Paul TK