dont take the cheap one with cable lugs on backside.
many are rated up to 50amps.
but when you have the connector inside a frame, and only 2 wires for the charging power, i measured up to 80°c (!)
one way is add huge awg 6 or awg4 wires to it that pushes some heat away from the connector.
easy way is the better quality stuff with 4 wires(fixed with screws on backside)
tested up to 60amps and 2850w of charging power -> 55°c on the hottest point.
also to avoid heat, take a charger with maximum or highest possible voltage to bring down the amps.
less stress for the coil, less heat for the coil AND controller AND of course MOTOR...Yes MOTOR because you are charging through one phase wire.
for example charging with the 70amp coil and only 24v PSU (~1700w) your ride after that starts with a 50°c "hot" motor + 44°c "hot" controller.
edit: to funny...checked now that you are the guy i answered allready xD