What to do with Battery when car is off the road (SORN)

prowla

I once kept a car in my garage because I changed job to one where I commuted by train.

I had to replace the battery twice, before the penny dropped and I sold the car.

If I were doing such a thing again, I'd get one of those solar trickle chargers.

Strider590

prowla wrote: »

I once kept a car in my garage because I changed job to one where I commuted by train.

I had to replace the battery twice, before the penny dropped and I sold the car.

If I were doing such a thing again, I'd get one of those solar trickle chargers.

They're pointless, in the brightest of sunlight (assuming 24 hours of daylight) they MIGHT just about keep up with the quiescent current drain on the battery.

They're usually 2.5watts MAXIMUM, which is around 0.2A or 200mA, the only "standard" for quiescent current drain on a car is that it must be under 200mA. So these solar chargers barely do anything at all.

I've known people swear by them, the same people didn't realise the lighter socket had no power with the ignition off, so I guess it was just a placebo effect.






OP, disconnect the battery negative/black terminal and place it on any car battery charger until fully charged, then just leave it disconnected. A maintenance charger would be a "nice to have", but it's probably not worth it for 2 months.
Typically you can store a fully charged car battery for 6 months without issue, as long as it's in good health and disconnected.

As for the other stuff related to keeping a car off road for that length of time, you didn't ask for that information and 2 months is unlikely to be much of an issue anyway, not at this time of year.

Marktheshark

Some cars will run rough for weeks if the battery is disconnected for as few days , anything petrol with a throttle body that gets gunked up.
Stalling is common until it eventually learns its positions.
Some like Micras, don't re-learn and can need new throttle bodies if they wont clean up or have worn.

Strider590

^^ That's bonkers.

Yes an ECU might need to relearn it's settings, igntion timing/mapping etc, but this is usually quite quick. I suspect what's happening here is people have other issues after a period of non-use, take the car in to a garage who haven't a clue what they're doing and just start replacing stuff.

=rizla=

Strider590 wrote: »

They're pointless, in the brightest of sunlight (assuming 24 hours of daylight) they MIGHT just about keep up with the quiescent current drain on the battery.

They're usually 2.5watts MAXIMUM, which is around 0.2A or 200mA, the only "standard" for quiescent current drain on a car is that it must be under 200mA. So these solar chargers barely do anything at all.

I've known people swear by them, the same people didn't realise the lighter socket had no power with the ignition off, so I guess it was just a placebo effect.






OP, disconnect the battery negative/black terminal and place it on any car battery charger until fully charged, then just leave it disconnected. A maintenance charger would be a "nice to have", but it's probably not worth it for 2 months.
Typically you can store a fully charged car battery for 6 months without issue, as long as it's in good health and disconnected.

As for the other stuff related to keeping a car off road for that length of time, you didn't ask for that information and 2 months is unlikely to be much of an issue anyway, not at this time of year.

If you do disconnect the battery then remember you're also disconnecting the alarm, and if your radio has a code you'll need that as well.


As Strider says a lot of cars don't have a 'live' power socket with the ignition off, however cars tend not to pull anywhere near 200mA's, if they did a standard 40AH battery would be flat in a week!!


My cheap solar panel gave about 70mA's on an average day, which proved to be plenty to keep the bike charged over the winter.

Strider590

=rizla= wrote: »

If you do disconnect the battery then remember you're also disconnecting the alarm, and if your radio has a code you'll need that as well.


As Strider says a lot of cars don't have a 'live' power socket with the ignition off, however cars tend not to pull anywhere near 200mA's, if they did a standard 40AH battery would be flat in a week!!


My cheap solar panel gave about 70mA's on an average day, which proved to be plenty to keep the bike charged over the winter.

Pretty much my experience with some of the "fancier" vehicles out there.

A bike battery is different kettle of fish, the capacity so low that it wouldn't take much to charge it at all AND I would imagine the quiescent drain is much lower than on a car....

What I would concern about is the possibility of overcharging on a small capacity battery, at I had a small 12v lead acid battery running a home made electric fence around my veg garden, topped up in the day by one of those solar charger panels, after a few sunny days is had the battery voltage up at 18v, which in turn damaged one of the cells, leaving me with a 10v battery.

EdGasket

Just do what you said in the opening post. Start it up every fortnight and run for 10 minutes to keep the oil circulated and battery topped up. If you have room on the drive, also move it back and forth slightly to stop the handbrake from seizing on. 2 months is a very short time anyway and you probably don't need to do anything at all.