Disconnecting battery for winter storage?

[AtlasM]

I've had my 135is in storage for the past month and change. I went to check on it today, and while it started up, it wasn't happy about doing so. I thought about taking the battery out and taking it home to keep it in better shape, because there's no power outlets in the storage unit which prevents me from hooking up a battery tender. But I'm concerned about a few things.

Since my car is a '13, there's no trunk lock cylinder. So I figure I'd have to make sure to leave the seats flipped down in order to crawl through to the trunk and pop the interior release to get back at the battery compartment.

Also, if I disconnect the battery, keep it charged up, then reinstall it a few months later, would I need to have the battery re-registered to the car by the dealer?

I have a battery jump start box, so today when I was messing around putting other stuff in the storage unit, I left the jump box hooked up to maybe get a little more charge into the car's battery. I suppose I could go there more regularly in order to hook up the jump box, but I don't really want to do something like hook it up, close up the storage unit and come back an hour later.

Has anyone else put their car up for the winter in a location where they can't hook up a battery tender, and come up with a good process?

[portine9]

Maybe an explanation of why to disconnect the negative terminal first and replace it last:

If you accidently hit the frame or metal parts of the car with the metal tool you are using to remove the negative wire from the battery nothing will happen. Not so with the positive connection. If you still have the negative terminal connected....you will have a lesson in arc welding which will be quite unpleasant and potentially dangerous. So in review, by removing the negative connection first and replacing it last you hopefully will avoid the possiblity of a nasty electrical short. coque iphone 6 plus etui iphone 6 plus

[Gray_Panther]

I remove the positive terminal and leave my window slightly open while also placing a towel where the trunk is that way I can close the trunk without fully closing it. When spring comes i just lift the trunk and reinstall the battery.
Been doing this for three years without reprogramming the car.

[AtlasM]

So...I ended up leaving the battery connected all winter. I went over to my storage unit every few weeks and started the car up. After that first time where it was kind of a hard start, I connected my jump start box each time I started it, just in case. I've now been daily driving it for a few weeks and there have been no issues starting it. I kept the jump start box in the car just in case, but I have yet to need it. I suppose maybe next winter I'll worry about disconnecting the battery.

[bmw1racer]

Originally Posted by AtlasM

So...I ended up leaving the battery connected all winter. I went over to my storage unit every few weeks and started the car up. After that first time where it was kind of a hard start, I connected my jump start box each time I started it, just in case. I've now been daily driving it for a few weeks and there have been no issues starting it. I kept the jump start box in the car just in case, but I have yet to need it. I suppose maybe next winter I'll worry about disconnecting the battery.

You should check the Magic Eye on the battery to see if it's green... If not, you might want to get a trickle charger.

[Solo_M_Tech]

Just use a battery tender, and leave it installed. SIMPLE solutions. They are cheap, and you'll be prepared for next winter! :-)

[AtlasM]

Originally Posted by bmw1racer

You should check the Magic Eye on the battery to see if it's green... If not, you might want to get a trickle charger.

I'll check. I have a solar trickle charger that has different attachments including lighter outlet (which is switched off when the car is off so no go there), OBD port, and battery clamps. Now that I'm daily driving it though it seems like it's getting a good amount of charging. This weekend I'm driving to Chicago and back, so that's a good 300 miles round trip to charge it up as well. I think the OBD port attachment should do the trick, if needed.

Originally Posted by HooningB2G

Just use a battery tender, and leave it installed. SIMPLE solutions. They are cheap, and you'll be prepared for next winter! :-)

Battery tender isn't feasible for winter storage for me, since all the self storage places I found around me don't have power in the units. If it was just chilling in my garage that'd be another story, but the reason I store it in winter is because I have a 1-car garage and 3 cars when you include my gf's.

[bmw1racer]

Originally Posted by AtlasM

I'll check. I have a solar trickle charger that has different attachments including lighter outlet (which is switched off when the car is off so no go there), OBD port, and battery clamps. Now that I'm daily driving it though it seems like it's getting a good amount of charging. This weekend I'm driving to Chicago and back, so that's a good 300 miles round trip to charge it up as well. I think the OBD port attachment should do the trick, if needed.

Hmm, I never thought about charging via the OBD port... I just use the terminals in the engine bay.

[Vigilante375]

Easy solution for you. Disconnect both terminals, wrap them in electrical tape (and put a couple strips on the battery too) and leave the rear seats folded down.

I've done that to my '12 135i for ~6 months and 3-4 months with no issues at all. I've done that to my motorcycles too over the winter months.

Thats easier than playing around with a dead battery and jumping the car off followed by driving the car for xx time to get it charged. And also since the storage place doesn't have an outlet to use a trickle charger.

[Olgeezer1]

Not having access to electrical where you store makes it tough. I guess your best option is remove the battery, bring it inside and keep it on a battery tender like the BMW Advanced Charging System (about $60. at the dealer). Do not use a trickle charger as they can overcharge and cook your battery.

[6MT_Addict]

You don't need to do anything fancy.

Disconnect the NEGATIVE (black) battery cable. Wrap a towel, cloth, or other insulator around it. Tuck the cable down beside the battery.

Walk away and forget until spring. Installation is the reverse of removal.

As said in the first reply you should only and always remove the negative battery cable first. A little battery history for you:

Hydrogen gas is a byproduct of car batteries being charged. By using the positive (red) terminal to break the connection, you are more likely spark the terminal as you re-connect it, OR if you contact a grounded portion of the body, frame, etc it will arc. If hydrogen gas is present during the arc there is a possibility of it igniting and causing a small explosion, worst case it would be complimented with battery acid.

Is this a likely thing to happen? No. Is it possible? Yes.

http://www.cdxetextbook.com/toolsEqu...erysafety.html

http://mechanics.stackexchange.com/q...alling-a-batte

[edisapimp]

Originally Posted by AtlasM

I'll check. I have a solar trickle charger that has different attachments including lighter outlet (which is switched off when the car is off so no go there), OBD port, and battery clamps. Now that I'm daily driving it though it seems like it's getting a good amount of charging. This weekend I'm driving to Chicago and back, so that's a good 300 miles round trip to charge it up as well. I think the OBD port attachment should do the trick, if needed.


Battery tender isn't feasible for winter storage for me, since all the self storage places I found around me don't have power in the units. If it was just chilling in my garage that'd be another story, but the reason I store it in winter is because I have a 1-car garage and 3 cars when you include my gf's.

I think the decision here is obvious. Drive the Jeep in the winter, kick gf into the snow, keep the 1 in the garage.

[AtlasM]

Originally Posted by bmw1racer

Hmm, I never thought about charging via the OBD port... I just use the terminals in the engine bay.

I hadn't heard of charging through the OBD port either. I wanted a solar trickle charger for my Jeep for the majority of the year when it's not my DD. The Jeep has a 12v outlet inside that stays on all the time, so a trickle charger with a 12v outlet would be perfect.

I wasn't planning on using the charger on the 1 since the interior 12v outlets disconnect when you turn the car off, but I saw this one which has swappable 12v, OBD and alligator clip connectors. So that seemed kinda cool for using with the OBD port as a way to leave the charger inside the 1 hanging out.



It was 35 bucks on Amazon. I haven't actually tried charging the 1 through the OBD2 port yet, just because it's still starting up fine and I'm slightly wary of doing something to fry the ECU, even though the OBD connector for the charger has a fuse on it.

Originally Posted by edisapimp

I think the decision here is obvious. Drive the Jeep in the winter, kick gf into the snow, keep the 1 in the garage.

She does get annoyed when I pull stupid crap like this with the Jeep in the snow...



I store the 1 in winter so she at least gets the garage half the time. If the 1 took up the garage all winter we'd have to dig out her Civic and the Jeep. And well, I'm sure I'd end up doing the Civic frequently.