charging battery

holmsy · 21-01-2007, 11:38 AM

anyone know if its ok to charge a battery with it still hooked to the car.
my brothers battery needs to be charged but the terminals are a pain in the *** to get off so will it cause any damage if it is charged while still connected. thanks

brmckinless · 21-01-2007, 11:51 AM

The car electronics will not appreciate it, most battery chragers are very dirty in their circuitry and put out all sorts of nasty electrical spikes, this doesn't hurt the lead acid battery but can put too much voltage across any electrical components still hooked up, replacing a computer or regulator is expensive.

For peace of mind I'd would always disconnect at least the positive. Install a battery isolation switch - that way you have the convience of leaving the battery where it is, but still protect the senative electronics.

**ebxr8240** · 21-01-2007, 12:17 PM

Connect charger leads with CORRET polarity, then turn charger on.. You'll be fine!!!
Its when jump starting where higher loads / amps that spikes happen...
Never connect anything under load in any electrical appliance.. Use the switch and you'll be fine...

**Mechan1k** · 21-01-2007, 12:23 PM

Have also read in some applications it is best to remove the plugs from the tops of the cells as well.

jonk · 21-01-2007, 01:48 PM

I use a constant flow/trickle charger on the ute. It sits there all year without being started or moved and the battery is fully charged all the time. People that store fishing boats away for long periods at a time use them, cost about $70.

Trickle chargers can be left to charge with the caps on the battery. But fast normal chargers the caps have to come off. Or go to a automotive electrical place and they'll just charge you ten bucks to get it out and have it charged in under 2 hours.

**Mechan1k** · 21-01-2007, 01:57 PM

That's pretty much was I was charged when I picked up my new generator for home.
Came with an empty battery .... Battery World charged me $12 to fill with acid and charge for me.