Connecting a battery charger directly to battery

[mermar]

Quick question: seems simple but the BMW battery has 1 black (negative terminal) and at least two red terminals. I popped the cap on the terminal cover closest to the trunk space (seemed to be roughly in the middle of the battery?) and connected my Deltran Battery tender Jr. I assume this is a safe means to connect the tender for long term storage? Can't say I have seen such a complet battery before with a variety of positive terminals, etc.
Thanks

[aussiem3]

Originally Posted by mermar

Quick question: seems simple but the BMW battery has 1 black (negative terminal) and at least two red terminals. I popped the cap on the terminal cover closest to the trunk space (seemed to be roughly in the middle of the battery?) and connected my Deltran Battery tender Jr. I assume this is a safe means to connect the tender for long term storage? Can't say I have seen such a complet battery before with a variety of positive terminals, etc.
Thanks

The easiest way to charge the battery is from under the hood where you have the positive terminal (under a red plastic cap) and connect the tender's negative to the earth.

[m3ray]

Originally Posted by aussiem3

The easiest way to charge the battery is from under the hood where you have the positive terminal (under a red plastic cap) and connect the tender's negative to the earth.

This.

There is also a charge point for negative (ground). See picture.

It's the easiest way and it is also the correct way. Don't monkey around trying to hook it up to your battery.

[mermar]

Ok - aware of this setup - but had read elsewhere on the forum people preferred a direct connect. Partly because connecting via under the hood did not allow their tender to show an accurate charge state?

[m3ray]

Originally Posted by mermar

Ok - aware of this setup - but had read elsewhere on the forum people preferred a direct connect. Partly because connecting via under the hood did not allow their tender to show an accurate charge state?

The manual for the car states to hook it up to the charge points under the hood. Some people connect it directly to the battery.

I haven't a clue why.

[mermar]

Ok - ill move to under the hood. Will see if my tender eventually shows a green light.

[m3ray]

Originally Posted by mermar

Ok - ill move to under the hood. Will see if my tender eventually shows a green light.

FWIW I connect under hood and it turns green within an hour. I guess some don't get it to turn green and connect it directly to the battery. Again I don't know why it works for some and not for others.

[White 13]

With a small amperage charge it can easily take 24 or more hours to charge a battery that is partially discharged. If it is taking a long time to charge it probably was a good idea to hook it to a charger.

Also, I use the under hood points with no apparent problem.

[schwin]

How often do you guys charge your batteries? I just recently started doing it monthly but not sure if that's overboard.

[m3ray]

Originally Posted by schwin

How often do you guys charge your batteries? I just recently started doing it monthly but not sure if that's overboard.

Mine is connected all the time, when the car is in the garage. Once the light turns green it's in storage mode and you can leave it connected indefinitely. I pop my head in from time to time, and make sure the light remains green. 3 winters doing this and not an issue.

[spdy330]

Originally Posted by m3ray

Mine is connected all the time, when the car is in the garage. Once the light turns green it's in storage mode and you can leave it connected indefinitely. I pop my head in from time to time, and make sure the light remains green. 3 winters doing this and not an issue.

I do the same.

[AlpineE92M3]

I just connected my Delran tender diectly to the battery in the trunk. Light went green an hour later. Doesn't really matter where you put it as long as it's connected correctly. Any three of the + caps work. I used the left most one on the battery.

[warp10]

my battery tender quick disconnect is attached to the under hood connectors.

[W///]

Originally Posted by schwin

How often do you guys charge your batteries? I just recently started doing it monthly but not sure if that's overboard.

Depends how often you drive the car. I drive mine at about 2-3 times a week, so a battery tender is not necessary IMHO.

I've always been told to do plug it up under the hood. And when you plan on jump starting, DEFINITELY go through under the hood, and not connect directly to the battery. That's just what I was told by BMW technicians one time.

[mermar]

Originally Posted by White 13

With a small amperage charge it can easily take 24 or more hours to charge a battery that is partially discharged. If it is taking a long time to charge it probably was a good idea to hook it to a charger.

Also, I use the under hood points with no apparent problem.

We were having a nice Fall - perfect cool Naturally Aspirated M weather - then literally overnight - a snow storm and now high in the teens. So caught me a bit unprepared for storage from a vehicle prep perspective (I guess only that the gas tank was at 1/4 tank). Looks like it will warm up next week so Ill go fill up the tank and put her away for the winter.

BTW - my little Deltran Battery Tender Jr took about 24 hours to go from red to green. Hooked directly to battery.

[schwin]

Cool thanks! My commutes are 3 miles one way so I just want to make sure I'm recharging the battery. 3 miles each time is certainly not enough!