This kinda sounds lowish, please share a photo of the label on the battery, or link to the website.
Actually, this is one of the amazing features of VESC based motor controllers!
Even if your battery has a current limit set to 20A, it is actually possible to have a higher current inside the motor, but only when they are spinning at low RPM (duty cycle). This is a great feature because it means you can have very strong torque at low RPM which is important for starting up.
As motor RPM increases closer to its maximum RPM, the current inside the motor will be reduced & be limited/determined by the Max Battery Current Limit that is set.
So rest assured, when Battery MAX current is set up correctly, you can rely on your vesc/focbox to protect your battery.
Here is a video showing 120 motor amps (I Motor), with battery amps (I Batt) of approx 12amps.
You can probably push this a little bit higher if you wanted to improve the starting performance of the esk8. Could try 40A, Remember, the current will start to get limited by the battery MAX current as your speed increases.
In common uses cases, it’s nearly impossible to run your motors at the maximum current for long periods of time. Especially if they have temperature sensors, as once a certain heat level is reached the current will automatically get reduced by VESC/FOCBOX. But not all motors have temperature sensors!
If you don’t have temp sensors, you must be more careful & monitor the temperatures during a ride. if you are a heavy guy & have many steep hills to ascend you will need to be careful about the max motor current you choose. Too high & your motor will overheat, too low and you won’t be able to climb the hill.
If you, or anyone else, requires more specific one-on-one help I do offer a paid service.