SAE J1772 is the American standard type 1.
It mainly refers to two charging voltages of
120V and 240V.
Level 1 will deliver just 1.4kw to the vehicle while a level 2 ranges from 6.2 to 7.6 kw, and level 2 chargers need a 208-240V, 40A.
Type 2 charger is widely used in Europe.
The OBC device is taking important role while alternating AC current to DC, then suppling power to lion battery pack.