After jump-start can I re-charge battery without driving it?

[solvitquick]

Sounds ignorant I know (in fact it is), but I have a flat battery so I need a jump-start (JS). But cos' I've got a temporary arm injury, I could not drive it for e.g. standard (?) 20 min.
After so many decades of driving, I always believed that after JS the battery would reach full power if I just kept in neutral and sat on gas pedal but never tested it! Am I right or do drive wheels have to revolve?

[HowardKennitby]

All that is required is for the engine to run. I have no idea how long it would take to charge battery sufficiently. In this cold weather you will need a good level of charge.
Are you sure the battery is just flat? Perhaps it is on the way out and not holding charge.

[Hopkirk]

No, the wheels don't need to turn.

However it won't charge much, even if you raise the revs a bit.

Ideally you need to connect it to a battery charger overnight.

Also why did it need a jumpstart? There is a possibility the battery is near the end of its useful life.

If it fails in late October, will it leave you stranded on a bad winter's night?
I suggest you consider replacing it.

[ChuckFickens]

Odd question...

the alternator is driven from the engine, not the wheels, so just sitting with the engine at a couple of thousand revs or so would charge the battery fine.

But if you can't drive the car, why bother starting it at all.... just leave it until you can drive it.

[HowardKennitby]

Investing in something like this may be useful. Halfords also sell these things.

http://www.machinemar...0-12v-battery-charger

The above will be OK most normal car batteries.

[ChuckFickens]

You don't need anything that big... you just need a battery conditioner...

http://www.battery2u....ctek-0.8-charger.aspx

[ChuckFickens]

BTW.... recommendation based on a autoexpress review..

http://www.autoexpres.../battery-conditioners

[Gizmonster]

The battery is not necessarily on its way out. Take it to a garage though - they'll check the battery and alternator for free.
My missus' car had problems starting a while ago, so she took the car to a local garage for them to test the battery and the alternator.
Battery and alternator were deemed fine, so the question they asked her (which is what I'm asking you) was, "when you use your car, do you mainly only travel short distances?"
My missus only uses her car to go to work (less than half a mile), go shopping (less than a mile) and visit her mum's (approx 2 miles). They told her to get on the motorway and go on a 10-15 mile round trip to charge the battery up. Everything was fine after that.

[solvitquick]

Ty HK, H and Chuck for your helpful answers - so I was right but good questions and advice. Chuck, I am afraid my (hateful) electronic engine-controller programmes will be lost if the battery goes ABSOLUTELY dead so that even a new battery will not restore them - bit like RAM versus ROM? Note at last garage-test all controller lights lit up but no start. Note car was laid-up after full-charge + MOT. Car/battery mileage just 16k.
Yours,
SIQ.

Scared of battery charger 'cos: (a) overdoing it might bend lead plates and (b) 40 yrs ago on a dark morning with a FIAT X19, cables were mixtures of red and black - you guessed it! reverse connected it and burned out the wiring loom!
Any advice re best battery charger with over-charge cut-out on the market anyone?

[HowardKennitby]

I am not aware of any modern charger that can overcharge to the extent of damaging the battery.

[solvitquick]

Wow! TY friends. I just wanna sort it out myself without pofessionals, a deficiency in my character but I'm a bit of a control freak even when stupid! Car and my arm could be laid-up further 8-12 weeks. Would like to move wheels a bit for tyres' sake and know car is OK and ready to go when I eventually drive again. Sorry cannot deal with all individually.
Unlike many ABers I will nominate best answer but it will be difficult as you all know your stuff.
SIQ

[solvitquick]

OK ty friends, as promised I will nominate a best answer - for my own and my motor's purposes. Very difficult and wish more ABers would nominate best answer (unfair to grab knowledge and disappear). Anyway for info-plus I, ONLY-JUST, chose: HowardKennitby! But ty everyone, very educative to me for now and future.
Regards,
SIQ.