Dumb**s alert: am I the first to drain it??

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palmermd said:
I think you are on the right track, but if one of the cells had less capacity and it triggered the shutdown, then charging will not give it more capacity, Nissan will have to remove the module with the faulty/low capacity cell and he will be back on his way.

I am not an expert here, but if one cell can cause this to happen, then it would be a design flaw. With the number of cells the LEAF has, there is a very possibility that one of them will be out of sync with others. This difference would be very noticeable during the last few miles and would trigger scenarios like Kelangst more often. And it would just get worse as the batteries age and they will get more out of sync more frequently.

Seems something wrong here and I hope it is wrong, because I will be very scared to drive when my battery capacity reaches less than 20 miles.
 
leaf561 said:
I am not an expert here, but if one cell can cause this to happen, then it would be a design flaw. With the number of cells the LEAF has, there is a very possibility that one of them will be out of sync with others. This difference would be very noticeable during the last few miles and would trigger scenarios like Kelangst more often. And it would just get worse as the batteries age and they will get more out of sync more frequently.

Seems something wrong here and I hope it is wrong, because I will be very scared to drive when my battery capacity reaches less than 20 miles.

Once you have a matched set of cells, the range estimates will be perfectly fine. This is a new car and this was probably the first time the pack had been discharged that low. Yes, be careful on your first trip when cycling your pack, but once you've done it, I'd not be worried at all about the pack. It will not get worse (cell balance or capacity change) with age. A matched pack will remain matched for life. They should all loose capacity together, and since the BMS is keeping the useable range away from the ends, you should not have to worry about it.
 
Just to chime in here ... I concur that this is A-TYPICAL ... it's this specific car that is exhibiting a problem; Nissan can fix that in short order. This should not / will not be the normal LEAF owner's experience. The "---" happened to me twice on Sunday, and in the first instance I was on an uphill trying to reach an emergency L1 location. I was still several miles away, I reached the location, and I never yet have seen the turtle, and I did not run out of juice.

But then something else happened ... I will create a new thread with a BUG report soon.
 
At work don't have time to read. But I did over 14 miles when my range dropped to 17 miles including 4.5 after the range display dissapeared.
 
Kelangst said:
I am realizing how specific I need to be when posting on the site or people misunderstand. While I mentioned I generally go 60-63 on the highway, this is San Diego at 3:45 in the afternoon. From the I-805 merge up past Encinitas I was doing between 18-35 on the highway. This is about 10-12 miles of the trip. I took it to 63 for about 8 miles before i saw it hit the 17 miles left and started slowing down just in case.
...
I was on city streets in San Diego for a good portion of the trip today. More than 1/2 of the trip this morning southbound was at 20 mph with traffic. I also didn't mention that I stopped at a Nissan Dealer in San Diego to charge for an hour before heading north.
...
But have a sinking feeling the title of my post is correct... Dumb**s. :)
I'd vote with you for the Dumb**s explanation, though I don't think there is anything dumb going on, just somethig of a design flaw in the human interface and our not being used to estimating more than anything. The problem is the range the car gives you is not that useful and you can get into trouble relying on it. You're puttering around so the car figures you have 17 miles left. Then you kick it to 65 MPH and start hitting the hills and the car decides that at that rate you have 4 miles left. In your mind you've gone from 17 miles to 4 miles in a heartbeat but to the car you've gone from 150 wh/mile to 600 wh/mile and it's just extrapolating current conditions into total range.

Just giving the kWh left would be better. Instead of a single number maybe a worst and best range based on your driving might also be a good idea. As it is the display is going to mislead some people.

Could also be a problem with the car but your explanation seems simpler. Hope it's not the car actually, that would present you with other issues, and condolences for your misfortune. It had to suck big time. But as you say this stuff will work itself out.
 
You know, I still don't see that it was said how many battery bars were left when the car was reading 17 miles...

When turtle kicks in there's zero bars, right?
 
SanDust said:
I'd vote with you for the Dumb**s explanation...I don't think there is anything dumb going on, just somethig of a design flaw in the human interface...Could also be a problem with the car...
If the car would not shut down despite the OP and the dealer following all documented procedures, doesn't that indicate a definite fault with the car? I'm looking forward to hearing what the dealer diagnosis is...

TT
 
LiIon batteries keep their voltage pretty stable so remaining capacity is mostly derived by keeping track of usage and charging. The only well known states are that the battery is 80% full when reaching 4.2 Volt during charging, completely full when drawing no more charging current at 4.2 Volt and that the battery is empty when the Voltage is around 3.1 Volt.

So there are two issues in this case:
- the battery was re-charged for one hour during the day but not to a full state. So bookkeeping was on its own for longer than normal.
- the battery is probably not often depleted, so the software doesn't commonly reach the bottom point for recalibration, it has to estimate the total capacity / battery health.

The display said 17 miles were left, but that turned out to be "about 5". That's a 12 mile difference. If you take the variance due to speed/terrain into account, maybe we are down to 8 miles. That's less than 10% of the total battery capacitance across more than one charging cycle. It probably doesn't get any better.

Concerning the software hanging, that could be anything unrelated. Not too many people have driven their Leaf to the point where it wouldn't even move an inch.

/M
 
throwing in one thing I was told - if something occurs in the first year of our ownership with any individual cell, Nissan will replace the entire pack. i was told this by the dealer when I purchased the car. The reasoning is that they want to take the data, and the entire pack to investigate what happened and determine if some fix needs to be deployed.

one other thought - if Nissan (through the dealer) does replace a cell or the pack, I think we should track it in the sheet. more data is good.
 
any new word on the issue yet? very interested in what they find out. doing interview tonight with online forum and would love to have something to report.

after reading the posts, i figured there would be 5 pages of others reporting how far they had gone without issues in your same situation. i have been where u were at over a dozen times. in fact, i have been waaaay beyond where u were at a few times, no issues here.

i believe you had an out of balance cell that caused the Leaf to shut down to prevent the cell from being damaged. as far as balancing the cell goes, it might be as easy as simply charging the pack back up. or it could be defective and need replacing.
 
Split the balancing posts into a new thread : http://www.mynissanleaf.com/viewtopic.php?f=9&t=2795&start=0
 
One thing we do know from the service manuals is the car is aware if any cell group reaches minimum voltage. That triggers an error with the 'check engine' light (CEL) on the dash, and also triggers a 'no drive/no charge' state with the car.

Were there any wrench, CEL, or other dash warnings? Or it more like a computer lock-up?
 
rdhauser said:
I would guess that some other issue caused the rapid decrease in range also. I'll also be interested in the resolution (please let there be one!)
He said he'd be gone for a week so it might be a while before he'll give us a report. But this post from martinr probably sums things up:

The display said 17 miles were left, but that turned out to be "about 5". That's a 12 mile difference. If you take the variance due to speed/terrain into account, maybe we are down to 8 miles. That's less than 10% of the total battery capacitance across more than one charging cycle. It probably doesn't get any better.

Probably just a combination of changing drive cycles and bookkeeping errors. IOW don't count of the display to be accurate all of the time. Someone in another thread with a Vectrix said that the range estimator on that cycle is affectionately called "The Random Number Generator".
 
After Kelangst's Leaf goes through a few more charge and drive cycles it would be interesting if he could run it down in that critical range again to see if the trouble repetes.
Or did I miss it?
 
Maybe you are the first, but it happened to me too! On 2/22 I was driving back from SeaTac airport back home, with 26 "miles" on the range estimation. Trip distance was ~ 15 miles. Some driving on I-5, eco mode on, no heating (at 32 F outside temp!) and around downtown the range is down to 8 miles (still plenty to get home, which was by then 5 miles away). At the ship-canal bridge it went into turtle, I barely got off the freeway. 2 Mile from home and after about half the distance it told I would have from the airport, i.e. 13 actual miles driven, it went dead. I actually managed to drive 400 yards in turtle mode. 10:30 pm, wife and screaming kids in the car (which was blocking the right lane of a busy road), just came back from the east coast, cars zooming by and honking, several near misses, I called Nissan for help.

Their initial response:
Sure we will tow you, but it will take an hour for the tow truck to arrive and we will only tow you to the next dealership (10 miles from my home). I said, well its an electric car and arent you supposed to tow me to my home when I run out of battery? Ah, its a battery problem, do you need a boost or a jumpstart??
It was hilarious..no clue about their own product....neither the operator nor her supervisor were aware of special roadside assistance for leaf-owners.

The experience with roadside assistance was quite sobering...
What I find scarier though is this gross mismatch in estimated and actual range. Any ideas if this is normal or a bad battery?
 
klapauzius said:
Maybe you are the first, but it happened to me too! On 2/22 I was driving back from SeaTac airport back home, with 26 "miles" on the range estimation. Trip distance was ~ 15 miles. Some driving on I-5, eco mode on, no heating (at 32 F outside temp!) and around downtown the range is down to 8 miles (still plenty to get home, which was by then 5 miles away). At the ship-canal bridge it went into turtle, I barely got off the freeway. 2 Mile from home and after about half the distance it told I would have from the airport, i.e. 13 actual miles driven, it went dead. I actually managed to drive 400 yards in turtle mode. 10:30 pm, wife and screaming kids in the car (which was blocking the right lane of a busy road), just came back from the east coast, cars zooming by and honking, several near misses, I called Nissan for help.

Their initial response:
Sure we will tow you, but it will take an hour for the tow truck to arrive and we will only tow you to the next dealership (10 miles from my home). I said, well its an electric car and arent you supposed to tow me to my home when I run out of battery? Ah, its a battery problem, do you need a boost or a jumpstart??
It was hilarious..no clue about their own product....neither the operator nor her supervisor were aware of special roadside assistance for leaf-owners.

The experience with roadside assistance was quite sobering...
What I find scarier though is this gross mismatch in estimated and actual range. Any ideas if this is normal or a bad battery?
WOW! Now that is scary (and embarrassing)! How in the world can a Leaf driver ever trust the "remaining range" indicator?? :eek: :eek: :eek: readings??
 
klapauzius, How long did you have the car at that point? How many 100% charges had it been? Was it the first time that low? Did you try to turn off and on to see if it would go again?
I bet DW is thinking you are crazy for buying this toy :roll:
 
Hate to think that the normal "safe range" at speed on the freeway might be about 33 miles: 80% (of charge) of 60 miles at 70mph, minus 15 miles to avoid this potential situation, 48-15 = 33!

Fortunately, that's exactly my roundtrip commute distance.
 
Wow...klapauzius, do you remember how many bars were left before you started your journey from the airport? From reading this forum, SOC is prob a way better indicator than that range estimate (although the closest to SOC is the bars, it's pretty grainy). 2 bars left (red) would have been 9-15 miles using 3miles/kwh type of driving.

Also, that was pretty low 32F temperature when you started your homeward trip! I wonder if the "low" ambient temp reduced the battery capacity even more than the bars would indicate, making things worst. eg. the 26 miles were based on your "warmer" battery when you left it at the airport. When you were ready to drive home, the computer wasn't able to adjust (or didn't know how to take temp into account) for temperature, and thus just showed 26 miles of the last estimate when the 32F would really give you 10!

Sorry to hear any kind of LEAF stranding, as it is not good PR. However, thanks for posting your experience since the very knowledgeable people here will give the rest of us more data and info so we would be more aware of what Nissan can't tell us, ie all the scenarios that could strand you. Experience is gold here, IMO.
 
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