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Battery Storage

We have a Pontiac Solstice which we will be storing for the first time this winter (WI). We are storing it at a rental storage unit with no availability of electricity. Since, as I understand it, we’d have to take off part of the fender to take the battery out, and I’d rather not do that, what’s the best way to maintain the battery over the winter?

The best way is to take it out and store it inside in a basement where the temperature is cool but moderate. But IMO, that’s not necessary for the time you talk about.

Otherwise, make sure it’s fully charged and in good shape before you store it, disconnect the negative terminal and bring a jumper battery or cables and another car when you take it out just in case. You should run Marine grade stabilizer in the last tankful you use for ethanol problems and do an oil change just in case. I would have the brakes checked too and have the pins on the calipers lubed. But that’s just me… Make sure the tires are pumped up and enjoy your vacation. If it’s just a few months over the winter, don’t worry if you do this minimum. If it’s cool where you store the car, it is better off.

Make sure the battery is fully charged before you store it. Then disconnect the “black” battery terminal so the battery is disconnected. A fully charged battery disconnected should make it through the winter fine.

In the spring you reconnect the black terminal and see if she fires up. I’d have a jump box handy just in case their isn’t enough juice left in the car’s battery to start a cold motor.

For this 1st start up turn the key to the on position and wait about 30 secs before hitting the starter to give the fuel pump a chance to build up fuel pressure and flow. Hopefully when you hit the starter it will fire up quickly then.

If the car is stored outside you could put a solar cell charger on the dasboard and it will trickle charge the battery and keep it from dying and freezing up.

I dunno, I think you’ve got a 50/50 chance of the battery making it through the winter. I charge my unused car up once a month. I find it hard to believe that taking the battery out requires taking the fender off but it may require some removal of some plastic pieces to get to it. At any rate if the battery doesn’t make it, you’re going to end up taking it out anyway or having the car towed.

Pulling the main fuse in the panel under the hood might be the simple way to stop the current flow from the battery.

The best way is to take it out and store it inside in a basement where the temperature is cool but moderate. But IMO, that’s not necessary for the time you talk about. Also, with the battery out of the car and stored away from the car, will reduce the chance of someone stealing the car. Few thieves carry an extra battery with them.

BTW don’t forget to check with your insurance company. They may offer a discount for the time when the car is stored, as opposed to driven.

The colder the temperature, the slower the self-discharge…batteries do not mind cold weather as long as they are fully charged…Battery “maintainers” and trickle chargers can sometimes do more harm than good, over-charging the battery and causing the positive plates to swell…You see the results of this all the time, the ends of the battery bulged out to accommodate the growing plates…Hopefully, the battery can be disconnected without removing the fender…Removing any parasitic drain will help it to survive the lay-up…

First question- what part of WI as the SE is not nearly as harsh and long as the NW?

Second question- how long? When I lived in that state winter storage could be 6 months depending on the car and severity of the winter/spring. Your battery will be completely discharged by then and starting to sulfate if you leave it in the car. BTDTBTTS.

@Caddyman is right.
Just as an add on; as you have gathered, there are more important considerations then a battery in good condition that you can easily disconnect. If your car is stored inside and free of domestic animals, place a sign on the door outside that there is poison inside and place Decon under the car in it’s supplied tray. Rodents are bigger problems.

Let me say, in over 30 years of storing cars and boats with starter batteries, I have never had a problem with a battery in good condition that I took the previous suggestions with, fail. Not only that, but battery storage in cool places does not harm the battery and may in fact extend it’s working life over one in use. Not to worry ! Just take a jumper battery back in the spring as it will loose some charge and spend more time worrying about the gas.

We’re in the SE part of WI. Plan on having the car in storage about 5 months, Dec through April. Does disconnecting the battery mess with the electronics? The storage place is close. Would running the car every 4 -5 weeks for 15 or 20 minutes do any good/damage? I did use quality gas stabilizer in it.
Thanks for the advice thus far.

“Would running the car every 4 -5 weeks for 15 or 20 minutes do any good/damage?”

Idling for 20 minutes will not fully charge the battery, it will contaminate the oil with moisture and waste a little gas.

Disconnecting the battery will remove all your station presets from the radio. The radio may also be tied to the security system. If the correct codes are not entered when you reconnect the battery, the radio can’t be used. It’s a radio theft prevention feature. This information will be in your owner’s manual. If it doesn’t say anything about radio theft prevention, then it is unlikely you have that feature.

When you disconnect the battery you will lose all the computer memory pre-sets you may have made, radio station pre-sets, and if it’s an “anti-theft” radio, be sure you know how to reset it…Same with “remote entry” codes…If your car is loaded up with electronic gizmos and gadgets, sometimes it takes a day or two to get everything working the way you want it again…But left connected, these same devices will slowly drain the expensive battery…If you could take the car out of storage and DRIVE it for 1/2 hour every month, warm it up completely, that would be good…But just starting it in place for 20 minutes of idling, no, that’s not good…5 months is nothing…Cars sit on dealers lots, unsold, for longer than that…

I agree with @Caddyman. If you can’t take it out and drive it for a sustained period of time, I wouldn’t bother idling it. 5 months is no big deal.

5 months is nothing…Cars sit on dealers lots, unsold, for longer than that…

Yeah, not in WI winter they don’t and those are brand new pristine batteries. For dealer lots with inventory sitting through winter, they keep the lot jockey busy with the starter pack just to shuffle them around to plow.

OP, I was in SE WI as well. West Bend prior to moving here. Stored many a car at places with no electric. If you can get the battery out, do it. If not, I’d be inclined to monitor the voltage about once a month. If it starts getting close to being discharged, then you could either hook it back up and use the car to charge it or run jumpers from your active car to the disconnected battery to charge it.

Running the car every few weeks does more harm than good, unless you run it enough to warm it up fully. Meaning a 30 min. drive on perhaps cruddy roads with salt residue. Better just to let it rest.