New Battery. Leave it on the Tender?

[bmwpower603]

I just purchased a new battery. (Genuine)

But I do not drive the car much. Is it okay to leave a “Battery Tender JR” on it all the time?

It’s a 12v 800MA. And it does have a “float” mode. I’m not to familiar with electrical. But could leaving the tender on it potentially damage the battery? Or will it prolong it?

Cheers-

[roastbeef]

i've read that leaving it on the tender constantly can be detrimental. i don't have any personal experience or knowledge to challenge that, so i sort of do both. i'll trickle it for about a week and if i get a drive in, i'll leave it off for a week or two, just to sort of give it a cycle.

[bmwpower603]

That sounds like a good plan to me. I will give that a shot.

Thank you.

Happy Motoring

[Richneerd]

Originally Posted by bmwpower603

I just purchased a new battery. (Genuine)

But I do not drive the car much. Is it okay to leave a “Battery Tender JR” on it all the time?

It’s a 12v 800MA. And it does have a “float” mode. I’m not to familiar with electrical. But could leaving the tender on it potentially damage the battery? Or will it prolong it?

Cheers-

In theory, you can leave the Battery Tender® Plus battery charger connected to a battery forever. That’s a really long time. Sales people like to say, “Just plug it in and forget about it!” However, practically speaking, it is a good idea to check on the battery at least once every couple of weeks. Strange things can happen. Sometimes a battery can have a weak cell that won’t show up until the worst possible time. Of course, that time is usually when the battery is connected to a charger, and you are out of town on vacation.

If something goes wrong, then you have to deal with the question of the chicken and the egg. Which came first? Did the battery fail because it was connected to the charger or did the charger fail because it was connected to the battery? Good luck sorting that one out.

With a battery and a charger connected together, it’s a much better idea to be proactive and anticipate problems, however unlikely they may be. In more than 99.9% of cases, nothing will go wrong. That still leaves about 0.1% where something might. Learn to respect electricity. A little common sense can go a long way.

Also consider this. No matter how good a product is, anything can break. In fact, everything will break, eventually. There are only 2 questions to be answered. 1) When will it fail? & more importantly 2) How will it fail? If a product is designed and built well, a manufacturer will set a long warranty period, usually several years, to support that notion. Deltran, and other responsible manufacturers, invest a tremendous amount of time, effort, and money to ensure that their products will fail in a relatively safe manner. For electronic products, at the very least that means no electrical shock or fire hazard.

The Battery Tender® Plus battery charger has a 10 year limited warranty, which is unprecedented among battery charger manufacturers. And it is listed with Underwriter’s Laboratories to comply with both US and Canadian electrical product safety standards for battery chargers used with engine start batteries.

For me, I leave it on for weeks on my other cars.

I rotate, whatever car is sitting gets the tender.

[redline9001]

I still have my original 2010 battery in my car... when I drove the car everyday I don’t put it on the tender. But it is always on the tender when not driving and my 11 yr old battery is as good as new .

I use a bmw/ctek

[Helmsman]

Originally Posted by redline9001

I still have my original 2010 battery in my car... when I drove the car everyday I don’t put it on the tender. But it is always on the tender when not driving and my 11 yr old battery is as good as new .

I use a bmw/ctek

That's my view as well, a proper charger with maintenance mode can be left on for ages. Trick is to reduce voltage well below "gas" level (even though AGM doesn't), say 13.6-13.8V and no harm done.
Not able to charge my car but left my boat batteries on year around.

[ItsGary]

Originally Posted by roastbeef

i've read that leaving it on the tender constantly can be detrimental. i don't have any personal experience or knowledge to challenge that, so i sort of do both. i'll trickle it for about a week and if i get a drive in, i'll leave it off for a week or two, just to sort of give it a cycle.

I kept my CTEK charger connected to my battery for 6 months or so when I didn't drive the car last year. No issues.

[Georgeair]

I have had my '08 on a Tender always other than the occassional days/weeks I'm driving it regularly (it's only got 40K total on it). I just replaced the OEM battery last summer. That's pretty good run.

Same with boat batteries - have an '09 and '12 battery that I'm still using today that are not on Tender in summer but are all fall/winter/spring.

I'd not hesitate to use one any time you can.

[BPMSport]

Leave it on a tender as much as possible.

CTEK or Deltran are the best choices. BMW branded ones are from these two brands. I have 5 cars on them at any given time.

[Expressivedrives]

Use smart charger, they do not harm your battery, leave them on. I have number of smart Ctec chargers, always on -- no problems whatsoever.