I would suggest making a new transformer with a core in the shape of a Y . One leg of the Y would hold a primary winding and the other two legs of the Y would hold secondary windings. an alternating current applied to the primary would produce current in the two secondaries . when the current is + it would be directed to one battery. when the current goes - it would be directed to another battery. A inverter could be used to produce the stored AC. I am a retired IBMer but do no have a shop or lab to ty this out. Doyle L Cox
I would suggest making a new transformer with a core in the shape of a Y . One leg of the Y would hold a primary winding and the other two legs of the Y would hold secondary windings. an alternating current applied to the primary would produce current in the two secondaries . when the current is + it would be directed to one battery. when the current goes - it would be directed to another battery. A inverter could be used to produce the stored AC. I am a retired IBMer but do no have a shop or lab to ty this out. Doyle L Cox