Keeping battery topped up when parked up without mains

[Andymharrison]

Hi,

Looking for a bit of advice on how people keep their battery topped up when a car is parked up for the winter without access to mains electricity?

My XC90 is used only for towing and we are coming to the end of our working season so the car will soon be parked up until Easter.

The last few years I have just tried to remember to take it out for a run every week or so but inevitably I get busy or forget which results in a low battery, reluctance to start and then needing a charge or long run, usually long run as getting the battery out of the boot is a pain. This can't do the battery any good, although the car seems perfectly happy to sit for ages and always fires straight up if the battery is good.

It is parked on the street so running a cable and connecting a trickle charger is not an option.

I was considering a small solar panel as I have a spare charge controller from our caravan, does anyone know if it is safe to charge in this way via the rear 12v socket, or suggest anything else?

Andy

[Metroman]

My situation is similar, I don't use the car from October to March and also SORN it so no opportunity to drive either. I have a solar charger from halfords that I plug in to the OBD diagnostic port (XC40) as the front 12V shuts down when with ignition.

Periodically I will run the engine at idle and get everything warm and also charge with a mains charger a couple of times , usually mid-term end of Feb. It has worked so far.

https://www.halfords.com/motoring/ba...0w-496278.html

[Forg]

Given that you can get battery starter-packs which store enough charge to kick start a 6L V8 engine over 10 times, and which are only about the size of a pair of portable hard drives, it MUST be possible to get a rechargeable trickle-charger which can keep the car battery topped up?

Some quick Googling didn't find anything, but it's hard to search for too ... you want something to maintain a battery which has an inbuilt battery, so the search results either show things for charging batteries or with a battery but not both!

[Andymharrison]

Thanks for the suggestions. I hadn't considered using the OBD port, that would be simpler as the rear 12v socket is always active but the tinted windows mean panel needs to be in the front.

I did search for a portable pack but didn't find anything either.

Since I have a spare charge controller, with a handy display to tell me state of battery I'm thinking of getting this 10w panel https://www.photonicuniverse.com/en/...-charger-.html and see how it goes this winter.

If I could get it off the road I'd probably SORN it, put a decent panel on the roof and charge via the towbar socket.

[Tannaton]

I think your bigger problem will be ruined brake discs from corrosion if you leave it on the street for 5 months or more.

Unless they're kept in a dry garage, cars need to be driven regularly I think.

[Whippy]

Be sure to leave parking brake off as well. (Granny, eggs, suck)

[ITSv40]

Originally Posted by Tannaton

I think your bigger problem will be ruined brake discs from corrosion if you leave it on the street for 5 months or more.

Unless they're kept in a dry garage, cars need to be driven regularly I think.

Exactly this ^^^^^^^

If the vehicle is road legal and able to be parked on the street, why not drive it a short distance every so often. My convertible is garaged and connected to a CTEK when not in use, but it is road legal and driven on dry days during the winter to keep it in good order. I start it up and drive for a minimum of 15-20 miles to warm everything up and dry the exhaust. I also operate every accessory to keep things free and working. It is thus always on the button and ready for any journey at any time.

[Baxlin]

Sorry, but why not just use the car, if it’s road legal?

Mrs B is (medically) unable to drive at the moment, but we decided not to SORN her car. So I just use whichever car’s keys I pick up first, mine or hers . It solves most of the ‘laid up’ problems - rusty discs, handbrake seizing, AC and battery deteriorating, petrol going off, tyres flat-spotting, mice under the bonnet etc etc. I also take the no-roof JZR for a run occasionally on dry days throughout the winter, for the same reasons, even though that lives in the garage.

[Andymharrison]

We need 2 cars for work just only for part of the year, the rest of the time we work from home and try to walk as much as possible so its not that unusual for neither car to move for a week.

The xc90 does get the occasional run to warm through, clean brakes etc, they don't seem to suffer much with rust though its a good while before I see them discolour, the xc70 though is rusty before you get indoors!

Its an XC90, not much point using the parking brake...

Its just not enough to keep battery good in cold weather and if I am away I don't want my wife having to dig up the boot floor and heave a heavy battery indoors to charge. We do this every winter, this will be 5th for this xc90 without problems other than low batteries.

Ideally I'd drive it once or twice a week and all would be well but I have chronic back problems, I forget, work gets in the way, I go away etc etc and the next thing you know the battery is low so I'm looking for something to keep the battery topped so that I know it will start when I get the chance to use it.

For £15 the little solar panel is worth a try, I just wondered what people in similar situations do.

[FreshAir]

https://bilthamber.com/product/atom-mac/

This can help minimise rusting of discs. Have not got any yet but have seen it used on brake discs.

I've got custody of a car that is now sat for who knows how long for my daughter so need to keep on top of battery charge and disc condition as well. It's getting more love and attention that she ever gave it...