royal flush

Must be well over 100 different brands of chargers--question-really any difference in brand as long as smart charging and ends in a float mode? I think all about the same and end up doing the same job?

ruxvette

Been using a Schumacher for many years. Walmart. Under $25.

FAUEE

There' a little bit of quality differences. Battery tender used to make theirs in the USA(in my homeland of Florida to boot!), not sure if all of them still are or not. They're who I use, no complaints,

jonjamis

I have had 3 battery tender jr and they all failed.

Using 3 CTEK now; they are working fine.

05 Wreck

I've used CTEK last 2 winters, with Optima red top. No problems, but I use their cigarette/12 volt adapter and have read this may cause electrical problems with the other electrical systems. Appreciate feedback on this while discussing OP's thread.

FortMorganAl

There are differences among maintainers but all work pretty much equally well. Kind of like walking 20 miles or riding a bike. There are differences in bicycles but all are so much better than nothing at all that it really doesn't matter which you choose.

Personally I've used Battery Tender Jr for over 10 years. The smaller/slower the better for the battery. It takes longer for a small one to recharge a depleted battery but time isn't an issue for this project. If you have to have a quick charge then get a second cheap high capacity charger. Chargers are for charging and maintainers are for maintaining. There IS a big difference there.

AORoads

That's actually good insight and advice by Ft. Morgan; it isn't the quickness or rapidity of the charger, because slower is better. I've had a Schumacher which eventually burned out and now a Ctek (quite a bit more cost). I've read of Joe on here who has had$10 Harbor Freight jobbies. Seems to work for him and others. I realize there are differences in brands, models and actual designs. I think "low and slow" tho is good advice. Heat is a killer in batteries, too, and charging causes heat.

pure zen

I have been using three Battery Tender PLUS models for nine

years and not one has failed.

Buggy650

I have a number of Battery tender plus and they all work great. Thought I would try a different on so I bought a Noco Genius 3500. It has more options but otherwise does the same job. I know people who run them on a timer for an hour a day but I just leave mine on all winter.

FortMorganAl

Also E=IR. Voltage = Current times resistance. There is going to be some resistance in the components and wire going to the battery. If you want a faster charge (more current, more heat, let time to for chemical reactions to equalize) then you need to raise the voltage. The circuit that measures the voltage or current is in the device supplying the current. That circuit sees the voltage there and not what is actually at the battery plates. So it has to supply a higher voltage than what it sees hoping to get the right voltage to the plates. A charger just looks at the current but a maintainer needs to look at the voltage. So a "big" maintainer will give a higher voltage when there is little current than a smaller maintainer. The smaller maintainer has a better chance of getting the right voltage to the plates of all batteries than a larger one.

But, again, pretty much anything is better than nothing. The difference between large and small is minor compared to the difference between charger and maintainer.

Jclgodale3

I've had 2 Battery Tender Jr's fail after about a year. I've had a small Schumacher for 2 years now on the Vette and just ordered another for the Lawn mower. Been happy with them

Null Pointer

I have five of these and one CTEK. I use them on vehicles, and on my lawn tractor and on the battery for my electric start generator. I've seen other guys on here that also use these.

4SUMERZ

Been using a Battery Tender Plus since 2009. Use it on the C6 for 5 months in the winter and on my Golf Cart battery for the other 6 months of the year. It's plugged in all the time in the winter, and about 5 times a week for the golf cart battery.

SUP54

I assume my 2007 Corvette has a battery charge port in the cigarette lighter socket in the front console? I see some on ebay that has the corvette logo on them. How do these perform?

SUP54

Must_Have_Z

Ctek ftw.

JerryC5

I'm not an expert, but I did stay at a Holiday Inn last week.

I have been using the Schumachers from Wal Mart for 15 years, and have had no problems.

mikeCsix

You want to look at the mfg'rs specs for float voltage, the lower the float the better as there is less water loss at the lower voltages. 13.02vdc to 13.20 is ideal. With the battery topped up it can sit on a tender for 6 months before you'd have to check the water level. You would also want to look at their stated conditioning voltages if they have it. This should be a high number. The pro's drive the voltage up to 16.2 (+-) to drive off the sulfur build up on the plates, to do so they monitor the battery temperature and limit current to a couple of percentage points. Often this is a user selectable function as you wouldn't want to condition the battery after each and every use, plus you would want it disconnected from the car so you don't overdrive your electronics at such high voltages.

Then there is the bulk phase which runs every time, typically tops out about 14 to 14.5 volts at max current the charger can supply.

I've seen some specs that use 13.8 as a float voltage. Much too high. That is the charge voltage cars used to run at in the '60's and '70's.

For a cheap battery charger, Deltran got much of it right. I've used them for years without issue and still have the first one I bought nearly 10 years ago.

HTH.

royal flush

[QUOTE=mikeCsix;1596233327]You want to look at the mfg'rs specs for float voltage, the lower the float the better as there is less water loss at the lower voltages. 13.02vdc to 13.20 is ideal. With the battery topped up it can sit on a tender for 6 months before you'd have to check the water level. You would also want to look at their stated conditioning voltages if they have it. This should be a high number. The pro's drive the voltage up to 16.2 (+-) to drive off the sulfur build up on the plates, to do so they monitor the battery temperature and limit current to a couple of percentage points. Often this is a user selectable function as you wouldn't want to condition the battery after each and every use, plus you would want it disconnected from the car so you don't overdrive your electronics at such high voltages.

Then there is the bulk phase which runs every time, typically tops out about 14 to 14.5 volts at max current the charger can supply.

I've seen some specs that use 13.8 as a float voltage. Much too high. That is the charge voltage cars used to run at in the '60's and '70's.

For a cheap battery charger, Deltran got much of it right. I've used them for years without issue and still have the first one I bought nearly 10 yea

I have an optima redtop--no worry about water BUT Optima wrote me and said 13.20 is min on float charge and nothing lower or will discharge--i dont understand what they meant--but BT Jr. only floats at 13.07-13.09 seems ok to me--

FAUEE

What they're saying is the float voltage must be 13.2 or more or it won' work. The battery will try to charge the maintainet.

bigger is better. Mine is a decent sized metal unit, not the crappy little plastic jobber. All the electrical components generate heat, and trapping all that heat in the unit in a little plastic box is a recipe for component failure.

mikeCsix

My comments were aimed at conventional lead-acid batteries.

To know if the Red Top batteries will be charged by the Deltran charger (which will charge AGM batteries), disconnect the Red Top and let sit for 24 hours. Use a good DVM and measure the battery voltage. If it is less than what Deltran uses as a float voltage, it will work and it will cover any load the car's electronics place on the system with the engine turned off.