[electricboats] 48V system cirucuit breakers? Vs. Fuses?

I'm using a 48V E-bike battery pack in a proof of concept type experiment.

The battery pack is rated at 20Ah, with a discharage of 50A, and max discharge of 100A.

The electric motor can pull up to 100A - so I'd like to put a circuit breaker in line with the battery, with the idea being that if someone accidentally gets too excited on the throttle, the circuit breaker would trip long before the BMS does.   (This is especially after the relevant post about the BMS protection circuits being an unknown quantity in sealed battery systems!)

Questions:

1) What is a good circuit breaker for a 48V system?  I'm thinking around 25-30A.   Most seem rated for 12V, some up to 48V.  I've only found one so far that is rated for 72V.

2)  Can I use a "48V (max?)" rated circuit breaker?   Is that intended for a 48V system that really goes up to 56-58V at peak charge, or is it really strictly limited for 48V (and intended for 32V systesms)??

3)  Is a standard 30A blade fuse ok to use in a 48V circuit?  Many don't seem to have voltage ratings...

Thanks,

John