It all depends on how you want to use the car. If it's for a predictable routine - To work 25 miles, home 25 miles, recharge overnight at 8 amps and same thing tomorrow, then the stock EVSE is all you'd need
But if you take a Saturday morning trip of 50 or 60 miles and then want to make another sizeable trip in the afternoon or evening, you'd be doing that in your ICE because the L1 charger isn't going to put it back quick enough to do that. We have those who are happy with L1 at 8 amps and then we have several folks who complain that the car didn't come with a 6.6 Kw charger like the later Leaf's do - It all depends on how you want to use the car
We have an L1 and an L2 EVSE mounted on the same board in the garage so we can select whatever we need for either of the cars and we probably average L2 recharging around 25% of the time - It used to be less, but we're both retired and our use of the cars is anything but predictable - We have an ICE, but we both hate to drive it around town. If we're not in a hurry, we usually charge L1 at 12 amps, but we would not be one of those who could live day to day on L1 alone
A couple weeks after we bought the car (before the Upgrade Service was available) we ran down to Home Depot and bought a 12 amp L1 EVSE for $369 - It had already become obvious 8 amps wasn't going to cut it. I used it for a week or so and noticed that the cord running to the car got uncomfortably warm and after several discussions with both Home Depot and the company that built the EVSE, I took it back and got a refund. At that point, we decided to cool our jets a bit and live with the car for a while to see what we really wanted/needed. When EVSE Upgrade came along, we jumped on that, as it was about $75 less money than the L1 12 amp unit we had returned to Home Depot and the upgrade was L2 capable. Ours was one of their earliest versions and it does not have the 'paperclip' adjustable feature
6 months or so later I built myself an Open EVSE which does have adjustable current and we tinkered with that for a few months. In the end, we quit messing with the current adjustments and use wither L1 or L2 as needed, both set at 12 amps. The Open EVSE on L2 will do 16 amps and if I wanted the fastest charge possible, I would need to set it for either 14 or 16, but we just leave it at 12 - That's about 90% as fast as the 3.3 Kw charger can do and I'm more comfortable not running it flat out all the time
My suggestion to you was - Figure out what you're pretty sure you'll want/need before you spend the least $$$ possible, only to discover later on that you wish you had gone in another direction, like we did - Luckily, we were able to get our money back. I know you hate to pay 'retail' but the upgrade service isn't really 'retail' as it's about half what a bulletproof, portable EVSE (which the Panasonic unit certainly is) would cost you if you bought it outright - It's the least expensive, most reliable thing of it's kind. Part of the cost is the 120/240 cord with the twist-lock plug they install on it. You put whichever pigtail you like on that plug and you can recharge from just about any outlet, anywhere. Use that feature once or twice and you'll be VERY glad you bought it. You might not like spending the money, but if you do, I think you'll be happy with it. . Probably much happier than you'd be with something you cobble into the J1772 connector which only gives you L1 at 12 amps
Don
But to choose L1 when L2 is available, or to limit the amps below what the i-MiEV will draw (and the circuit supports)... this, I don't really understand.
