No. Putting two 24V batteries in parallel would still give you 24V. You would need to wire them in series to get 48V, but I would suggest buying either a 24V charger or a 48V battery instead of wiring two 24V in series.
I used it to bring all batteries to the same level before parallel installing them. It's not as fast as the EG4 as it only pulls 8A from a standard AC outlet, but worked for me.