Charger Installation for 2 cars

Hi, when I try and charge both of my ford focus electric autos the circuit trips. I am using the 120 Volt cable provided. My idea is to have 2 independent outlets installed off the circuit panel, one for each car and continue using the provided cables. How many amps for each circuit should I specify? Where specifically is this documented?

You need to run an independent circuit all the way from your circuit breaker to your wall outlet. The reason why you're tripping is because both outlets are on the same circuit breaker.

They should preferably be 20 A circuits. Normal level 1 charging is 12 A, so you could get away with a 15 A circuit, but it's just as easy to do it right.

But if you are going to the trouble to add another circuit, why not also add a 220 V 20 A outlet as well. Then you can also use a portable level 2 charger in the future. Or better yet, add a 220 V 40 A circuit and you can add a 6 kW class EVSE at a later time.

Or to put it another way...if you have a single 6 kW class station, you can easily handle the two cars more easily than with two L1 portables.