Note #10 wiring is capable of 30a continuous it's just the breaker is almost surly 80% duty rated. It's possible to find breakers rated for 100% duty cycle but they by far are not the norm and I'd think the only place you could find one would be a wholesale/commercial place or probably online.
So again as long as you had a 30a 100% duty rated breaker, #10 wire, all connections secure and a quality 30a outlet, you should be able to get away with a continuous 27.5a(what a Nissan draws) load. If any of these are not the case things will get very warm and would be unsafe.
2012 SL purchased used 2/'16
2013 S w/QC purchased new
Juicebox Premium 60a L1/L2 EVSE, Ebusbar 16a L1/L2 EVSE
'12 EVSEupgrade'd 20a L1/L2 EVSE, '13 EVSEupgrade'd adjustable 6-20a L2, 6-13a L1 EVSE
Zencar 13, 20, 30a L1/L2 portable EVSE
GE Durastation 30a