[major]

Originally Posted by Scania

it is a KER-System of my bike, it still have a control circuit to drive the motor.

Ahhh! Formula 1 teams spend $millions for KERS. And you want the answers for free here I wish I had them for you kid.

This equipment isn't all that expensive for a bike. I suggest you just wire the thing up and start experimenting. Even if you can't get an F1 perfect system, you'll learn a lot and can do a good report for a grade (or mark as you call it).

But will it damage the battery if always charge & recharge the battery?

You're talking the ripple? I don't think so. But I have no idea what type battery you have. Is battery management important? You bet. Will ripple current hurt it? I doubt it. In fact for Pb-acid, ripple may help.

I hope you can understand this and it is helpful. I have worked with students my entire career. And don't mind throwing a few facts or ideas your way. But ultimately it is your project and you have to do the work.

Good luck and keep us posted.

major