"Hidden Buffer" in kW remaining / Miles remaining

I was thinking on the way home today as my gas gauge was below the E and my distance to empty (dtw) display was flashing -----, knowing that I still had at least another 15-20 miles left before I was "truly" empty, I began to wonder if the gauge on the Leaf is going to have a hidden buffer as well. As in, when it gets to 5 miles left and starts to shut off unnecessary items, will I really have 5 miles left, or will I have more like 10 or 15 miles left. I would think that since car makers have been putting this buffer in vehicles since the dawn of time, there would be that same buffer in the Leaf.

On principal, I am against such hidden buffer. It's the same fake-out feature my <relationship redacted> <used/uses> when setting <his/her> clock forward five minutes to make up for a "bad habit" of arriving late to <take-your-pick>. :lol:

I prefer a very accurate this-is-how-it-is / deal-with-it.

Don't try that in a Mercedes, you could wind up on the side of the road explaining to your wife why you ran the car out of gas when the gauge said "E". Or so I've heard :shock:

You will need to get the GM Volt for the hidden buffer

With all the warnings and the limp-home mode and all that, plus batteries' natural tendency to recoup a slight amount of power when resting, and it's going to be VERY HARD to run out of juice in the LEAF Compared to a gas car where if you ignore the warning it eventually will happen all of a sudden.

If the "Miles Remaining" says 25 miles and you have 30 miles to go to get home, and there is not a long downgrade to your garage, then you should be considering "activation" of your "Plan B", right?

Plan A:
In driving (my very first LEAF "trip") the 65 freeway miles home from Fontana to south Orange County, I will enter my "home" destination into the Nav system, and see what (if anything) it says.

Then, I intend to calculate (monitor) my trip's "Spare Miles" (Remaining-Miles minus Miles-to-Go). If the "Spare Miles" starts dropping, I will drive a little slower, since there might not yet be any usable "edie-stations" anywhere along my route.

Plan B:
Hopefully, at least some of the Nissan dealers (like Tustin) will have active, available chargers by then, and I can stop in for 6 or 12 miles worth of L2 (30 or 60 minutes).

Plan C:
Assuming no "public" e-stations, I will play "knock, knock, who's there" with some residences. "Ho, Ho, Santa's Helper needs to feed his e-sled, will you help?", I might say!

An extension cord, a bottle of champagne, and a bottle of sparkling apple cider (for those who do not "drink") might be helpful provisions.

xtremeflyer said:

I was thinking on the way home today as my gas gauge was below the E and my distance to empty (dtw) display was flashing -----, knowing that I still had at least another 15-20 miles left before I was "truly" empty, I began to wonder if the gauge on the Leaf is going to have a hidden buffer as well. As in, when it gets to 5 miles left and starts to shut off unnecessary items, will I really have 5 miles left, or will I have more like 10 or 15 miles left. I would think that since car makers have been putting this buffer in vehicles since the dawn of time, there would be that same buffer in the Leaf.

Click to expand...

To answer the question - yes, Leaf has "spare" battery. With about 4 kwh left, you will start getting "empty red light". First the car will slow down a bit and stop AC and other accessories. After a couple of miles, it will put you in crawl mode. See Nissan Leaf site "range" topic for details.

But, that 4 kWh "reserve" is part of your "usable" 24 kWh, not part of the "unusable" part of the battery, I think.

garygid said:

But, that 4 kWh "reserve" is part of your "usable" 24 kWh, not part of the "unusable" part of the battery, I think.

Click to expand...

Possibly. But when people say "reserve" - they are mostly talking about early warning.

Right, a warning that you are down to your last 4 kWh (about 16 miles). A slightly earlier "warning" is when the "Miles Remaining" gets down to 20, or 25, or 30 miles. The warning is there, but many do not pay attention until something "drastic" happens, because they are accustomed to cars with a "hidden" reserve.

What would be the point of the fuel guage in an ICE if the thing only registered empty as the vehicle shut down? The empty indicates you should focus on getting to fuel and not running one more errand. In range percentage terms the low and empty warning in Leaf appears similar to an ICE vehicle.

Ignor the warning at your own risk. Although we all expect some great stories soon on just barely making it and others that get stuck.

Here, things are spread out enough that I might have to drive 5 or 10 miles out of my way to even see if an e-station is available, adding perhaps 20 miles to my trip.

Then, if that one is "dead" (or in use for 6 more hours), will I have enough "e-fuel" to investigate another?

I will usually have to do "charge-planning" long before the "reserve" warning lights up.

Of course, if you are in a local area with lots of known e-stations, the situation would be different, and the "16-mile" warning should be plenty to get you some extra e-fuel to get yourself home.