dgpcolorado said::?: Why you consider the charging finishing a bit early to be "efficient" is a puzzle. Efficiency of charging has to do with how much of the power coming from the wall gets to the battery. Charging at 120 Volts, 12 Amps, is about 75% efficient. Charging at 240 Volts, 16 Amps is about 86% efficient. Charging a 2013 model at 27.5 Amps would be a bit more efficient than that, as will charging to 80%, as opposed to 100%. (The reason has to do with the fixed overhead to charging the car, involving pumps, cooling and the like. Shorter charging time, less overhead.)Assaf said:...Finally as to inefficiencies and overhead, in our experience the trickle charge time actually needed is usually some 20% shorter than what our car computer says, so it's quite efficient for our needs.
If you want to make the argument that the cost of the electricity wasted with Level 1 charging is small compared to the cost of installing a Level 2 charge station, then few would disagree. The advantages of Level 2 charging have to do with speed and convenience. If you don't need much charge each day and don't need to preheat the car in a very cold climate, then trickle charging will suffice, as you have found.
Consider the possibility that some people buy the LEAF, expecting to use it for a 50+ mile commute using the supplied trickle charge EVSE (because that's what Nissan includes with the car, right?). How happy are they going to be when they find that they charge all the time and still can't seem to fill up the car? Nissan expected that LEAF drivers would use the Level 2 charging for which the car was designed and which was likely to provide a more satisfying user experience. The Level 1 EVSE was provided for opportunity charging where Level 2 was unavailable and Nissan didn't want new LEAF owners to assume that the very very slow trickle charge EVSE was the only way they could charge the car.In short, I'm quite satisfied with trickle, and would prefer Nissan not to pre-emptively define what gives me enjoyment. They should focus on tips and full disclosure on practices that increase battery and EVSE life, and of course driving range, and leave the specific consumer choices to the consumer.
If you manage ok with Level 1 charging fine. But knocking Nissan for recommending against it, for quite valid reasons, seems unwarranted.
The problem with many of the above assertions is that they aren't true. I use 120 volt charging only, and have no trouble with my 45-50 mile commute three days a week. Some of you are instantly assuming that I start with a 100% "buffer" the first day and have less left every day, but nope, I get to my desired 90-95% charge on all three of those days, with about 5-6 hours left over. If I actually wanted to charge to 100% it might take just about all of the down time, but there is no need to charge to more than 83% or so for a 50 mile commute at mixed speeds, and that includes both not using the last 20% and leaving a 10% reserve for unexpected side trips. I only charge to 100% by accident, and have no range anxiety at all. I use an outlet strip (not a surge protector) for the EVSE, and leave it on when not in use. If I ever did need to turn it off, I'd use the strip. Nothing gets more than "warm" in the charging setup, and this is during one of our Hottest Summers ever. During my off days I charge to 80%.