AC/DC converter and battery charger

[Edward]

I have a friend who suggested the following to charge your trolling batteries on your boat: Assume you have two 12 volt batteries (24 volt system) with an on-board charger. Bring aboard a third fully charged battery, an AC/DC converter, and a second battery charger. Connect the converter to the third battery, the on-board charger, and charge the two trolling motor batteries. Then connect the second charger from the third battery back to itself to re-charge it as it is depleted charging the two trolling motors. I told him it cannot possibly work, but was not able to convince him. Can anyone, is understandable terms, explain why this will not work?

[djk50164]

I hope this is not a joke but here is the answer. The device I think you are talking about is called an inverter(changes DC to AC. Well your system sounds great but it will not work. Anytime you change power from AC to DC or DC to AC there is a power loss or efficiency rating. I am not sure of your rating but it somewhere around 85%. So you don't get 100% of what that battery is deliviring. So your battery would charge for awhile but it would never charge the batteries to full capacity and it would not charge itself. Putting that second charger on would only drain the thrid battery faster. I think this is called perpetual motion...doens't work. Hope this answers your question.

[Wall@y@]

Why would anyone want to this much work to do a simple task of charging a two battery bank or even a three battery bank when you have at your disposal the best array of multiple battery charging systems available that perform the job flawlessly and with so little effort of plugging the charger into 110 vac power? There has been years of engineering in both batteries and chargers to provide us with the very best state-of-the-art battery power for our fishing needs. I can't imagin not drawing from this source of knowledge to make our fishing days less troublesome.

[Danny]

If you want the best technology for charging and this is your concern to charge on the water and other means also. Then check out the stealthcharging web site. Technology that has brought great reviews and will extend battery life.