Last I heard, it's vital to keep an electrical load continually attached to the turbine generator. The load can be either your battery or a heating element.
An electrical load makes the generator hard to turn. With no load the turbine is free to spin wildly, resulting in ruined bearings. Or the blades can shatter, with danger to property and/or lives.
With that said: You can adapt any number of charge controller circuits. Such as for solar, etc.
You must design it to detect voltage on the battery. This is the easiest way to control charging.
Stop charging at 14.5 V. Or switch to taper charge above 14 V.
Or use hysteresis as a method of taper charging. Switch charge on and off between 13.5 and 14.5 V.
You'll probably need a diode to prevent reverse current flow.
When battery reaches full charge you must design the circuit to divert generator output to a load.