Can I Recharge Car Battery While Its Still Connected In Car

Posted in Car Batteries

I don’t want to take the battery out as there is some kind of tube connected to it. Have bought a battery charger and want to know if I could just charge it up without disconnecting anything. Car is a Passat 1600 1997 R. Any help would be really appreciated. Thanks.

There are 11 Answers for "Can I Recharge Car Battery While Its Still Connected In Car"

    1. trucker dad says:

      yes will not hurt anything

    2. pedro7of9 says:

      ive done it with no ill effects

    3. kevin d says:

      yes just make sure you hook up cables right

    4. desert camel says:

      yes,it will cause no probs at all…BUT,If you putting the bonnet down make sure the positive battery charger terminal doesn’t touch earth/cars body…

    5. bobweb says:

      Why take any chance at all with your car’s electrical system? Anyone can disconnect the black ground cable to the battery before hooking up the charger, so why not do it? The connectors should be removed anyways for a good cleaning as in the video below. A battery charger is not designed to provide the same charging conditions as your car’s alternator. Jump starting a car can also cause damage under some conditions. Never perform arc welding on a car without disconnecting the battery whether the ignition is on or off. ^(

    6. Tan Man says:

      The car does it all the time
      You are just using a different source to do it
      Remember it is only the battery that is receiving the charge
      The cars electrical system is turned off
      And the battery is always ready to put 100% of what it has into any wire of the car already

    7. Big Daddy says:

      yes you can – you may have a little problem if you have a car alarm and don’t forget that the clock will be running – the two will not be using much juice but will be requiring some – I had to disconnect the pos cable only and left the battery in the car – you may want to take this opportunity to clean the post and cables

    8. Tiffany_loves_diamonds says:

      My battery is really dead. How long will this charge take? Can I try to start my car in a couple of hours with the battery charger still connected? Thanks, Tiff

    9. chucksterelmo says:


    10. Marty says:

      Bobweb, one of the benefits of charging the battery is that you won’t need to disconnect it, I took mine out of a BMW before and when I reconnected it my stereo was asking for the code, it was wrote there in the manual, I entered it, didn’t work, the stereo wasn’t the original one, I couldnt get the code anywhere, I emailed the relevant companies with the serial number with no luck, so then I had to buy a new stereo.
      No harm is done to any electrics, 12v in at ??amp, just like what the alternator does everytime the engine is started