MOSFET that has no problem with long charging period?

We're in the process of creating an electric unicycle like the ones here. We already have a design that we're sure will be competitive in the market once out. Now, I am assigned on working with the charging circuit. I was thinking of using power MOSFETs but I'm not quite sure which one should I get. Do you have any recommendation? Preferably 60v. The charging period is critical so I'd like to have a MOSFET that has no problem with long charging period.

Use a mosfet(s) rated for continuous duty at the maximum charge current.

Hundreds of issues here:

Is the mosfet used as a DC switch, a PWM, or linear regulator?

What is the system peak voltage?
What is the peak current through each MOSFET?
What is the charging circuit?
Do you have room for a heatsink?
What is the battery size / voltage / capacity?

ak

What is your Charging CIRCUIT?
SCHEMATIC?

What is the battery chemistry? Lithium batteries can catch fire or explode if not charged properly.
I suggest you go to Battery University.