New Leaf 2016 SL, Bad Battery?

[DNAinaGoodWay]

It does vary, but I don't think that I've seen more than 32. Certainty not bad cells like this OP. A few people here have had CVLI tests and that's what's I'd recommend.

 

[Cryptizard]

Could this be the "Shunt Order" setting? There was an argument whether it should be 8421 or 4812.

That was it! Thank you! Changing the order in LeafSpy made it show correctly that all cells but 51 were discharging.

If one of the balancing transistors is failed on the "ON" position, I would expect the LI-ion battery controller to throw DTC P3062: BYPASS SW. But I don't know how long it will take the controller to come to that conclusion.

Hopefully whatever is discharging (or previously discharged) cell-pair 51 is NOT the shunt and the imbalance will be corrected over time with no further issues.

I have just gotten LeafSpy so I can't say for sure, but it has been behaving as I described here (substantially reduced range) since I bought it over a month ago, and I charge it every weekday overnight with an L2 charger. If anything it has gotten worse. Now that I have LeafSpy I can keep an eye on the exact voltage and see how it is changing, but I don't feel like the situation is improving on its own.

The other possibility, a bad cell is quite unlikely - you have captured the battery state at the full charge. If that one cell was weaker, it would be the highest-voltage one after charging, not the lowest one. But to further diagnose the issue, you could capture a screenshot at the low battery state too. If the cell 51 is still the lowest voltage cell (very likely, this matches your observation of sharp decline in the range while driving), it's just some initial imbalance in the pack and it could even out when left long enough on the charger.

I will get this screenshot tomorrow after my commute. Thanks for all your help!

 

[Cryptizard]

It does vary, but I don't think that I've seen more than 32. Certainty not bad cells like this OP. A few people here have had CVLI tests and that's what's I'd recommend.

Sorry for my ignorance but what is a CVLI test?

 

[RegGuheert]

Sorry for my ignorance but what is a CVLI test?

Here is my detailed transcription of how to perform Cell Voltage Loss Inspection (CVLI) so that anyone with LeafSpy can do the test.

 

[GerryAZ]

Could this be the "Shunt Order" setting? There was an argument whether it should be 8421 or 4812.

That was it! Thank you! Changing the order in LeafSpy made it show correctly that all cells but 51 were discharging.

Could you post the shunt order setting which gave the correct Leaf Spy display? I have been trying both shunt order settings first on my 2011 and then on the 2015 and have been unable to tell which setting is correct. I would like to see screen shots after full charge and discharged as far as you feel comfortable with (at least low battery warning, but very low battery warning or lower would be best) before commenting in detail, but you clearly have manufacturing defect(s)--either bad cells or instrumentation (cell voltage measurement errors).

Gerry

 

[Cryptizard]

Could you post the shunt order setting which gave the correct Leaf Spy display? I have been trying both shunt order settings first on my 2011 and then on the 2015 and have been unable to tell which setting is correct. I would like to see screen shots after full charge and discharged as far as you feel comfortable with (at least low battery warning, but very low battery warning or lower would be best) before commenting in detail, but you clearly have manufacturing defect(s)--either bad cells or instrumentation (cell voltage measurement errors).

I just got back from a 50 mile drive and ended up with 23% battery left according to the dash display. This is the graph with shunt order 8421, which appears to be correct.

It shows the SOC at 45% while the GIDs are only 23%. Am I correct in interpreting that as the batteries having 45% charge but only 23% is "usable"? I was watching the dash while I was driving and the battery display went from 65% to 30% in about 10 miles of driving, with occasional jumps like 55 -> 50 in less than a mile.

I have an appointment at the dealership on Friday, any suggestions on how I should present this information to them?

 

[Cryptizard]

Sorry for my ignorance but what is a CVLI test?

Here is my detailed transcription of how to perform Cell Voltage Loss Inspection (CVLI) so that anyone with LeafSpy can do the test.

Is that information up to date for the 2016 Leaf? Because I have 3 cells that are substantially below 3.712V (the poster there made it seem like even getting to 3.712V was uncommon, let alone below that), and even the "working" cells are pretty close to it. I don't know what the correct values for these are though, maybe it only looks like the good cells are "close" because the scale is messed up due to the fact that the other three are so low.

 

[RegGuheert]

Sorry for my ignorance but what is a CVLI test?

Here is my detailed transcription of how to perform Cell Voltage Loss Inspection (CVLI) so that anyone with LeafSpy can do the test.

Is that information up to date for the 2016 Leaf? Because I have 3 cells that are substantially below 3.712V (the poster there made it seem like even getting to 3.712V was uncommon, let alone below that), and even the "working" cells are pretty close to it. I don't know what the correct values for these are though, maybe it only looks like the good cells are "close" because the scale is messed up due to the fact that the other three are so low.

3.712V is approximately at LBW, so going below that level is no big deal. The test is not to see if any cells go below 3.712 volts. Rather you need the lowest cell to be below that level before you make the CVLI calculation since the LEAF battery is top balanced.

In your pack, cell pairs 15, 51 and 75 currently fail CVLI. But it seems clear that the shunts are being commanded properly. The question is whether they are working properly or not.

As it appears right now, the spread in cell voltages is NOT decreasing. When you took a picture at the top of the voltage range three days ago, the spread was 113 mV. Now at the lower end of the voltage range it has increased to 121 mV. But that, in itself, does not tell us much since it is expected to have a higher spread at the lower voltages.

The bottom line: your pack SHOULD fail (badly) a CVLI test at a dealership today. But I would be inclined to make measurements with the pack FULL occasionally over a couple of weeks to see if the spread gets lower over time. If it doesn't, then there is something not working properly.

 

[Cryptizard]

The test is not to see if any cells go below 3.712 volts. Rather you need the lowest cell to be below that level before you make the CVLI calculation since the LEAF battery is top balanced.

Oh that makes sense, thanks.

The bottom line: your pack SHOULD fail (badly) a CVLI test at a dealership today. But I would be inclined to make measurements with the pack FULL occasionally over a couple of weeks to see if the spread gets lower over time. If it doesn't, then there is something not working properly.

I will keep checking it, but based on the behavior I have seen (mileage actually getting worse over the last month) I don't think the spread is getting better.

 

[GerryAZ]

Thanks for posting the shunt order that gives correct display. Since the voltage spread is almost constant from full charge to the lower SOC you just posted, I wonder if there are errors in the A/D converters for the three low cell pairs so the LBC (lithium battery controller aka battery management system) thinks those cells are 100 mV lower than the others. If so, it would attempt to balance the pack and limit discharge based upon that information which would cause the reduced range you ar seeing.

Regarding your trip to the dealer, I would take photos of the dash displays and document a range test on level roads from full charge down to very low battery warning (VLBW) to show the lower than normal range. Referring to Leaf Spy information will not be beneficial because Nissan only recognizes data from their Consult system.

Gerry

 

[johnlocke]

Just a quick note. Your tire pressures are low. 35 psi is way low for this car. Most people run 40-43 psi. Tires will still wear evenly and you pick up 3-5 more miles per charge. Not world shattering but every little bit helps.

 

[RegGuheert]

Just a quick note. Your tire pressures are low. 35 psi is way low for this car. Most people run 40-43 psi. Tires will still wear evenly and you pick up 3-5 more miles per charge. Not world shattering but every little bit helps.

Regarding the bolded part: I would say that the tires will NOT wear evenly if you leave them at 35 PSI, but if you increase the pressure to 40 PSI they will. At 35 or 36 PSI, they will wear out on the edges and not in the center, indicating the pressure is too low.

 

[Cryptizard]

Just a quick note. Your tire pressures are low. 35 psi is way low for this car. Most people run 40-43 psi. Tires will still wear evenly and you pick up 3-5 more miles per charge. Not world shattering but every little bit helps.

Oh cool, thanks for the tip.

 

[DaveinOlyWA]

Just a quick note. Your tire pressures are low. 35 psi is way low for this car. Most people run 40-43 psi. Tires will still wear evenly and you pick up 3-5 more miles per charge. Not world shattering but every little bit helps.

Regarding the bolded part: I would say that the tires will NOT wear evenly if you leave them at 35 PSI, but if you increase the pressure to 40 PSI they will. At 35 or 36 PSI, they will wear out on the edges and not in the center, indicating the pressure is too low.

Reg is correct. there is also a lot of evidence that sidewall stiffness is not sufficient enough for a car that heavy with a super low center of gravity. higher pressures makes the car stiffer with better handling on turns, roundabouts, etc.

there is NO safety based reason to run your pressure lower than 44 PSI. At this level, your tires will last longer and you will have more range.

 

[Cryptizard]

So I have taken it in to 3 different dealerships, had them run all the tests they can (they called the tech line) but they say everything is fine. It is especially confusing because at the last dealership they gave me a loaner car which was a 2015 Leaf with the smaller battery, and it actually gets the same or slightly more mileage than my 2016 SV. It is definitely not my imagination.

At this point I don't know what I can do. I live in Maryland, which does have a lemon law, but I would have to be able to demonstrate that the issue "substantially impairs the use and/or market value" of the car.

 

[armelwani]

I'm just getting started with the process you're going through. Nissan clearly has some bad batteries from the initial run of 30kwh packs. I don't know why they don't want to make this right. If this was an ICE car with a manufacturing defect they would get it fixed ASAP, but Leaf's don't get treated the same.

Fortunately I'm in California, so the lemon law is a little more friendly to the consumer. I really don't want to have to go that route, but I will if they leave me no other choice. I'm updating on another thread (http://www.mynissanleaf.com/viewtopic.php?f=44&t=20924&p=473542#p473542) if you want to follow along, hoping for good news before the end of this week.

 

[johnlocke]

Can we hear from all the 2016 Leaf owners about where their battery stats are now? If you own a 2016, please use LeafSpy on your car and post the battery stats and current mileage. Even if your battery is pristine, let us know! There may be a problem with the battery in general or it might just be a bad batch but the only way to find out is to gather as much data as possible.

 

[ElectricEddy]

Can we hear from all the 2016 Leaf owners about where their battery stats are now? If you own a 2016, please use LeafSpy on your car and post the battery stats and current mileage. Even if your battery is pristine, let us know! There may be a problem with the battery in general or it might just be a bad batch but the only way to find out is to gather as much data as possible.

And manufacture date (not delivery date)

 

[Cryptizard]

Update on this horrible situation... Nissan sent out a factory technician to look at the car and they maintain that nothing is wrong with it. It now gets only about 50 miles per charge in the cold weather, despite consistently saying that my driving efficiency is 3.5 miles / kWh which works out to 3.5 m/kWh * 30 kWh = 105 miles. On Carwings it also shows that when I go from 100% to very low battery it only uses at most 19 kWh out of the 30 kWh, and LeafSpy shows that when the car is in turtle mode it still has 30% SOC.

BUT there are no check engine lights on and their computer says nothing is wrong so they can't do anything about it. I told the dealer when I bought the car, I have to drive 60 miles round trip to get to work and if my car ever has less range then that I might as well not have a car. They said oh no don't worry even in bad conditions it will never get less than 80. Right now I am paying for a car that I cannot use, and they refuse to admit that there is even a problem with it. This is the worst experience I have ever had with a car and I will NEVER buy a Nissan again or recommend it to anyone.

 

[rcm4453]

You should have the tech at the dealer take the car out and run it from 100% down to turtle so they can see for themselves that getting only 50 miles isn't normal.