New Leaf 2016 SL, Bad Battery?

[Cryptizard]

Your description of miles driven and remaining charge sound about right for a well-balanced nearly new 24 kWh battery. You should not have to deal with this on a new car, but maybe it would be worthwhile to get Leaf Spy to look at the car's battery data independent from the dealer.

Gerry

So you're suggesting that Nissan installed the wrong battery type (a 24kWh one, rather than the 30kWh) in the OP's 2016 SL?

I don't know that he's doing that... before I even saw the above quote, I was thinking I would ask the OP, "not to be rude, but are you absolutely sure you received an SL model?"
I would estimate the chances of Nissan putting the wrong battery in an SL at way less than 1% of 1%... I would put the chances of a Dealer trying to "put one over" on a customer at greater than 50%. :shock:

It has the quick charge port and the VIN number shows SL when you look it up online.

 

[johnlocke]

He shows 75AH in the histogram so it has to be a 30 KWH battery. 24 KWH batteries never show more than 64 AH even if it's the new lizard battery. His problem is most likely the two low cells. 113 mv is a huge imbalance in the battery. That ought to be under 20 mv. He can try to DCFC after running the battery down a few times to try to improve the balance. The dealer is not likely to be much help here unless he can show a reduced range due to a defective cell. I'd keep a record of the mileage between charges and percent battery useage. If he can show significantly reduced range, he might get Nissan to listen. Otherwise it might take a lawsuit claiming deceptive advertising about the range or waiting for the battery to drop 4 bars.

 

[LeftieBiker]

Topping the car off with L-1 and letting it charge until all the charge lights are out should EQ the pack as much or more than L-3 is likely to do.

 

[Cryptizard]

He shows 75AH in the histogram so it has to be a 30 KWH battery. 24 KWH batteries never show more than 64 AH even if it's the new lizard battery. His problem is most likely the two low cells. 113 mv is a huge imbalance in the battery. That ought to be under 20 mv. He can try to DCFC after running the battery down a few times to try to improve the balance. The dealer is not likely to be much help here unless he can show a reduced range due to a defective cell. I'd keep a record of the mileage between charges and percent battery useage. If he can show significantly reduced range, he might get Nissan to listen. Otherwise it might take a lawsuit claiming deceptive advertising about the range or waiting for the battery to drop 4 bars.

I told them that I was getting 80 miles on a charge and they basically said that was within range of normal and they couldn't do anything because there were no error codes.

 

[Cryptizard]

Topping the car off with L-1 and letting it charge until all the charge lights are out should EQ the pack as much or more than L-3 is likely to do.

I charge it fully every night with an L2 charger. Are you saying I should drive it to turtle and then charge it to full with the trickle charger?

 

[LeftieBiker]

I charge it fully every night with an L2 charger but I don't have an L1, except for the trickle charger. Are you saying I should drive it to turtle and then charge it to full with the trickle charger?

No, there is no compelling reason to empty the pack if you've done it recently. Just connect the charge cable that came with the car (the actual charger is onboard) and let it finish charging from wherever it is now with that. The longer time the car spends finishing the charge may help.

 

[Cryptizard]

No, there is no compelling reason to empty the pack if you've done it recently. Just connect the charge cable that came with the car (the actual charger is onboard) and let it finish charging from wherever it is now with that.

Ok I'll give that a shot, thanks for the suggestion.

 

[DaveEV]

Ok I'll give that a shot, thanks for the suggestion.

Yep, and make sure the charge timers are off.

For sure, cell 51 is way low in voltage when fully charged and is certainly what's causing your issue. What does it look like as you drain the battery lower?

It is curious that for some reason 51 is being discharged, when 52 should be. I wonder if it's a bug in LeafSpy or if perhaps the pack was somehow wired wrong. Cell 75 is an outlier, too.

 

[Cryptizard]

For sure, cell 51 is way low in voltage when fully charged and is certainly what's causing your issue. What does it look like as you drain the battery lower?

I'm not sure, I just got the ODBII connector today and I haven't driven anywhere. I will monitor it next time I do and post the results back here.

 

[camasleaf]

Definitely unbalance or bad cells. In my 2011, at 69000 miles, the cells are within 16mV from each other, fully charged.

 

[johnlocke]

He shows 75AH in the histogram so it has to be a 30 KWH battery. 24 KWH batteries never show more than 64 AH even if it's the new lizard battery. His problem is most likely the two low cells. 113 mv is a huge imbalance in the battery. That ought to be under 20 mv. He can try to DCFC after running the battery down a few times to try to improve the balance. The dealer is not likely to be much help here unless he can show a reduced range due to a defective cell. I'd keep a record of the mileage between charges and percent battery useage. If he can show significantly reduced range, he might get Nissan to listen. Otherwise it might take a lawsuit claiming deceptive advertising about the range or waiting for the battery to drop 4 bars.

I told them that I was getting 80 miles on a charge and they basically said that was within range of normal and they couldn't do anything because there were no error codes.

When you say you're getting 80 mi to a charge is that to turtle, VLBW (7%), LBW (13%), or some other value? If you're using the miles actually driven and then adding the Guess-O-Meter number to that you could be way off. Best guess is to use miles driven plus 1 mile for each percent of battery power left. I.E. 56 mi driven plus 36% battery = 92 mi range. Not perfect but usually close. I always reset the tripmeters and the mi/KWH on the energy screen after a charge. I never use the 12 bar gauge, it's not accurate enough. I just scroll to the % battery screen on the main display and leave it there.

Nissan is not going to help you unless the battery throws a code or you lose 4 bars. I have heard of them replacing a defective cell if the car has the right fault code. I don't know how bad the cell would have to be to cause that though

 

[Cryptizard]

Best guess is to use miles driven plus 1 mile for each percent of battery power left. I.E. 56 mi driven plus 36% battery = 92 mi range.

I've only driven it down to 15% but using that formula the range on that trip would have been 75 miles. I normally drive 60 miles round trip and have 20% of the battery left so that would 80 miles per charge average.

 

[DaveinOlyWA]

Thanks for all the info guys. I got an ODBII adapter and tried LeafSpy just now and it shows 27 kWh at full charge. That seems a little low, but not low enough to be causing the drastic drop in mileage that I am seeing. I have not tried a turtle test, the lowest I have gotten the batter was about 18% I think. The whole thing could be an instrumentation error because it does seem to start discharging more slowly at around 25%. I will try to do a full to turtle test and see what what I get.

I am also having some trouble figuring out all the information that I get from LeafSpy and the documentation doesn't really help. What are the "normal" values for some of these supposed to be? For instance, this is the graph of my battery cells:

According to the documentation, red means that the cell is being bled to increase balance, but all of them are red except for one blue one. I have seen other screenshots from LeafSpy where they are all blue. And one of the bars is dramatically lower than the others, does that mean something?

Also, this is the graph of voltage differences, which are higher than I have seen in other examples that people have posted but is it high enough to be worrisome?

Thanks for all the help everyone, I appreciate it. If there is some guide that I can read to answer these questions myself please point me toward so I don't have to keep bothering you nice people :-D

you have a bad cell. at full charge with minimal load, your voltage delta should be under 30 mV (which is actually pretty high) and yours is 113 mV.

this means the voltage on that one cell will drop to the cutoff voltage way before the rest of the pack and will shut the car down. It needs to be replaced. now as your SOC gets lower the voltage delta gets larger. Generally speaking my car has to be below 10% SOC to see deltas as large as yours

 

[Firetruck41]

This seems like it should fall under the battery defect warranty (not battery capacity warranty). Collect all the documentation you can, as well as screen shots showing the bad cell. If the cell doesn't balance out on its own, I would insist on the warranty being honored.

 

[RegGuheert]

It is curious that for some reason 51 is being discharged, when 52 should be. I wonder if it's a bug in LeafSpy or if perhaps the pack was somehow wired wrong.

Yes, this is what I noticed. All cell pairs EXCEPT 51 should be discharging (RED), but in this display, all except cell-pair 52 are being discharged. Like you said, this could be due to a setting issue with LeafSpy, but perhaps it could be due to a wiring defect.

 

[nenik]

Could this be the "Shunt Order" setting? There was an argument whether it should be 8421 or 4812.
You could try to open Leaf Spy and in Settings, Battery section, change the "Shunt Order" to the other one than you currently have in there.
Then verify the cell statistics screen, whether it now shows the lowest bar as blue.
That would be the correct behavior - the car can't charge an individual cell, it can only discharge, so if only one cell is lower, it needs to discharge all other cells, then possibly charge the whole, now balanced pack to the real full charge.
Given the very limited balancing current, it may need several days worth of charging to get the pack back in the shape.

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.

There is a third failure mode possible, a leaky cell (a cell that has a slight internal short or some other little conductive path over it), so it looses part of its charge (or its charging current) all the time. Actually, I could imagine the balancing transistor for given cell going bad and constantly discharging the cell. Leaf's balancing current is about 10mA per cell, so under this scenario, it would still take few months to kill the pack (it will be totally unusable in less than a year, but you would observe significant changes in about a month).

 

[RegGuheert]

Welcome, nenik. Excellent first post!

Could this be the "Shunt Order" setting? There was an argument whether it should be 8421 or 4812.
You could try to open Leaf Spy and in Settings, Battery section, change the "Shunt Order" to the other one than you currently have in there.
Then verify the cell statistics screen, whether it now shows the lowest bar as blue.
That would be the correct behavior - the car can't charge an individual cell, it can only discharge, so if only one cell is lower, it needs to discharge all other cells, then possibly charge the whole, now balanced pack to the real full charge.
Given the very limited balancing current, it may need several days worth of charging to get the pack back in the shape.

Thanks for the details on shunt order. Hopefully OP will try this and report what he sees.

There is a third failure mode possible, a leaky cell (a cell that has a slight internal short or some other little conductive path over it), so it looses part of its charge (or its charging current) all the time. Actually, I could imagine the balancing transistor for given cell going bad and constantly discharging the cell. Leaf's balancing current is about 10mA per cell, so under this scenario, it would still take few months to kill the pack (it will be totally unusable in less than a year, but you would observe significant changes in about a month).

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.

 

[cwerdna]

at full charge with minimal load, your voltage delta should be under 30 mV (which is actually pretty high) and yours is 113 mV.
...Generally speaking my car has to be below 10% SOC to see deltas as large as yours

On the first point, agreed completely. IIRC, when I look it's generally in the teens or less but if greater, under 30 mV sounds right.

I've never taken my current car to very low % SoC, so I've never seen voltage delta anywhere near 100 mV but I've heard it can get huge when the battery's nearly depleted.

 

[DNAinaGoodWay]

Not necessarily. This was taken after LBW:



If the balance doesn't improve, they should get a CVLI test.

 

[lkkms2]

DNA - good note, but your battery T = is in the 50s F. Try measuring again next summer when hotter and go lower SOC than LBW.