Twin Battery Question

[John Straub]

A friend of mine has a "Twin Battery" car. He would like to use a trickle charger on it. How would he hook it up? All my cars have a single battery, so I have no idea what to tell him.

Thanks,
John

[jrbennett]

The batteries are connected in parallel in the vehicle, so you should be able to charge both at the same time by connecting to just one of them.

I personnally charge one at a time. I doubt it makes a difference although it makes me more comfortable.
I disconnect the ground strap of the battery being charged. Once charged I reconnect the cable and disconnect the other one to charge.

[edmayo]

John, the alternator charges the batteries through the left side battery connections and then goes through the cross over cable to the right side battery, the ground of course is common so it doesn't matter. So you could attach the charger connections to the battery posts of the left side battery and it would be the same as the alternator does, or you could attach the positive charger cable to the left battery positive post and the negative charger cable to the right side negative post, its all the same.

[John Straub]

Thanks guys! I'll pass this along.

John

[HughH]

Ed
couldn't you also attach the positive charger cable to the right battery positive post and the negative charger cable to the left side negative post... wont the charge go back the other way??

John, the alternator charges the batteries through the left side battery connections and then goes through the cross over cable to the right side battery, the ground of course is common so it doesn't matter. So you could attach the charger connections to the battery posts of the left side battery and it would be the same as the alternator does, or you could attach the positive charger cable to the left battery positive post and the negative charger cable to the right side negative post, its all the same.