this assumes that you have a newer, faster Type 2 charger and that you have a newer EV that has a 300mi range (on avg). But unfortunately, THESE PERFORMANCE NUMBERS ASSUME THAT YOU DRIVE 55 MPH IN IDEAL WEATHER CONDITIONS WITHOUT AN INCLINE, SO....
you will actually have less range and need more charges (in reality it is illegal to go 55 mph and thus you HAVE to drive 65 mph which decreases range by 15% (actually more since friction is increased at higher speeds as well but we'll be generous to the Green Folk here).
Thus, the range could be estimated at 300mi x 0.85 = 255 miles per charge. which means 118 charging stops on a cross country trip of 3000 miles which means = 177 additional hours beyond the trip itself of listening to this harpie in a Walmart parking lot.