Hi,
depending on how you use the batteries I bet you need an inverter as well to use the batteries if you not have one already.
You can select a inverter/converter combo allowing to apply the right charging profile.
an example for your further research is the
Xantrex Freedom XC line.
They include an automatic transfer switch, charge upto 80amp meaning you charge two 100 amp batteries in little over 2 hrs with a generator.
Happy researching
Mike