augy

Is it safe for me to charge a battery while it isn't in a car? Can I just hook it up like I'm jump starting it and just let it charge?
I'm trying to fix a car that's sitting in a garage with a dead battery, so I can't get a 2nd car in to jump it. Thanks.

Kai

That's the way a dead battery should be charged. Run down to Sear's or something and pick up a battery charger, they aren't too expensive and come in handy on occasion. They usually have settings for "jump," quick charge, and long charge. Set it for long charge and let it go.

v8guy

I think he wants to take the battery out, hook up jumper cables to it, and charge it with another car. I guess that would work fine, but make life easy on yourself and go down to Sears and get a charger like Kai said. They are handy to have and you can get a decent one for under $50. I think mine was $25, maybe $30, at Sears.

augy

Cool--thanks guys.

Kai

Oh... that would put a serious strain on the other car's alternator and battery. It's not something I'd try, a battery takes a lot of juice to charge.

augy

Well, what differentiates charging a dead battery inside the car from outside the car? My friend said it would take a lot longer to charge outside, but I don't understand why; there's no other part on the car which holds the charge besides the battery, so what's the difference?

redcivicforever

I was thinking its becuase of the alternator not being with the battery if its out of the car as it is when the battery is in the car so it is harder to hold the charge? Of course I honestly don't know, but maybe...

Kai

Inside the car, it's connected to a dinky alternator that has to keep the car's battery charged while under electronic strain from the car. Adding another battery adds more load to the poor thing.

Pluging it into the wall is connecting it to the local power station. Charging a car battery is nothing compaired to something big, like a freezer.

augy

Understood, but why would a battery charge better inside a car than outside?

Kai

Because the alternator doesn't put out as much power as a wall socket, plus it's a strain on the alternator to charge a dead battery... a real battery charger isn't under any strain worth mentioning.