Pretty much what it does except it will be a pulsing DC current and voltage. It take full filtering to become pure DC. The output voltage will about .707 of RMS input voltage. This is called half wave rectification. Most Briggs AC single wire stators will be only capable of about 3 amps DC though there is regulator that can be added that will get you to 5 amps. Without the regulator you will only need a 4A 200PIV diode. Larger current rating for diode is okay just gives a larger safety margin. The surge current rating is much larger than the continuous rating mention above. When installing the diode the anode goes to the stator side and the cathode goes on the battery side; otherwise you will get a negative DC output.
Just remember to insulated things once assembled to prevent shorts.
With this being basically using to recharge the battery I would not worry about it pulsing as many battery chargers does the same thing. This why my 12V 5A solar panel charges a battery just as quick as my 10A battery charger.
