Battery Chargers

I don't think so. I'm pretty sure you need to buy a 36 volt charger. I don't know why, but I can imagine bad things happening if attempting to hook chargers up in series.

http://www.guide-to-golf-carts.com/golf-cart-batteries.html

I've got to agree, especially if you don't know the internal wiring of the charger. There are some really cheap ones out there that have poor isolation from the line side to the load side, it is quite possible that you might find yourself somehow interconnecting both sides together. Better to get the appropriate device.

You could, in principle, but it is risky in practice. Before you turn the AC power on, the battery may already be 36V. You do not know if the 36V will divide equally between the 3 off 12V chargers, if it is too high on one, it could cause damage. If the 36V battery is flat when you turn on the first 12V charger, will it put current backwards through the other un-powered 12V chargers - will that do damage? The chargers may all have current limiters, the one with the lowest setting could absorb all the surplus voltage which can be 3 x its design level!

I have a 24V trolling motor in my boat. I charge the two 12V batteries with a 12V charger. But, when I charge the batteries I disconnect them from the boat system. I use wire connectors to connect the positive terminals of both batteries together, and connectors between the negative terminals. I then connect the charger's connectors to the positive of one battery and the other to the negative of the other battery. There is good information on the site www.batteryminder.com

Actually I already have the 36v charger which I got for free (cost new is $450). I was just curious if three 12v chargers used in series would work.

Ron,

IF they were TOTALLY isolated outputs, and your battery was totally isolated, then in theory, yes, you could do this. The problem is the big IF's that are present. With large capacity batteries and high-output chargers, the results could be bad if those if's were to come back to bite you.

Tom D.