Charging a car battery at night?

Question

I recently left my car lights on by mistake and discharged my car battery. Fortunately I have a battery power pack to start the car. Is it ok io run the car to charge up the battery at night when the lights are on. Someone told me this will do more harm but the barrery seems to have charged ok

Answer 1

The car battery will charge just from ordinary driving, it doesnt need to be left on over night... Use your power pack to start your car, and go for a short drive (20 mins max) which will leave enough charge in the battery to start the car next time you wish to use it.

Source(s):

My massive brain... ;)

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Answer 2

It won't make any difference to your battery by charging it at night with the lights on.
If you used the slave to start the car, then charging it with the lights on may take a little longer, but will not cause damage to the battery.

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Answer 3

It should be fine, but you are putting additional stress on your
alternator.

It wouldn't hurt to put the battery on a slow charge ( if you have one ). Just follow the instructions for that particular charger. You
can do this even the next day if you like.

It really won't harm anything if you don't. But don't tempt fate either.

Good Luck to you

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Answer 4

It will just take longer to charge, since you are running your headlights.

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Answer 5

You didn't need to charge your flat battery. That will occur when you are driving. If you can start the car with your power pack I can't see the problem. If you drive very short journeys perhaps you should take your power pack with you for the first time. But the alternator will be sending maximum amps to the flat battery and assuming the battery is in good condition it will recover it's full charge quickly.

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Answer 6

actually it is against the law in the UK to leave a vehicle unattended while the engine is running,far better starting car in the morning and going for a good 20 mile run at a speed of 30-50 mph to give the battery a good charge (don't try charging battery up with the lights, radio, or heater,wipers on )better just getting an ordinary battery charger and charge the battery up overnight on a trickle charge until fully charged, (this could take longer than 8hrs depending on battery)

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Answer 7

if it starts up fine .... leave it alone. whoever told u that is stupid or an @ss

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Answer 8

If it is starting and running good dont worry and it is hard on the alternator but it seems to be running fine so dont worry.

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Answer 9

if u just leave the car ticking over with lights on then u will not get very much charge,but if u r driveing for 20 min or so and providing yr battery is in good nik,then yes this will charge enough for u to start the next morning,avoid useing any radio, heater fan etc while u do this.

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Answer 10

Get a battery charger. Running the car over night is just plain wrong and expensive.

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