According to the 2011 Nissan
According to the 2011 Nissan Leaf owner's manual, 120 volt charging is not meant to be a long term solution. Is this also true for other EVs, or later model LEAFs?
Direct from the owner's manual:
Trickle charge
Trickle charging is not recommended for regular use. Trickle charge can be used when it is
necessary to perform an emergency charge at a destination such as a friend’s house.
Trickle charge uses the EVSE (Electric Vehicle Supply Equipment) or an SAE J1772 compliant
cord set to connect the vehicle to an AC 110 -120 volt, 15A dedicated outlet. The outlet
should be protected by a dedicated circuit breaker or fuse to avoid overloading the circuit
or other electrical hazard. It takes approximately 21 hours to charge the Li-ion battery from discharged (low battery charge warning light illuminated) to charged. See “How to trickle charge” later in this section.
Personally, I abide by the owner's manual (they put it in there for a reason). I only charge at 240 Volts or DC QuickCharger. But, I have done "emergency" 120 volt charging twice, when I didn't have a choice, twice in the year I have owned the car.