vectrix regen breaking

hi all i have a burning question if you lived on top of a hilly area and only used a little power of the vectrix to get to near this hill and then traveled down the hill and used this regen breaking would this corse an over load ? would this course the batteries to over load them selves ? or would the regen breaking not be as affective as batteries pretty full and there would be less resistance in the regen breaking ?