[help] Rapid battery discharge, "limited motor power", and sporadic power output at temp. < 30F and > 40% motor power.

[SageBrush]

When I pick up the car, register a complaint with the manager (general or service?) that my car is experiencing a failure accompanied by a significant safety risk, and that I feel the techs aren't listening to or addressing my concerns to my satisfaction.

That isn't the problem. The problem is that Nissan has constrained them to only address battery issues that generate DTCs or result in 4 or more lost capacity bars. They may be happy with this, but there is no point in antagonizing them for following Nissan policy. Just get those codes generated.

My reason for making sure the dealership has a clearly documented complaint is mostly to time stamp the problem for warranty eligibility.

 

[LeftieBiker]

Yes, absolutely. My point is that it should not be in the form of a hostile "complaint." The OP just needs to have the "issue" documented. Then, when a DTC appears, the dealership will likely act on it. If they don't, then that is the time to start raising Hell over it. There is no point in generating mutual enmity with a dealership that can't do what is desired under the current circumstances.

 

[GerryAZ]

I suggest you approach it in a "matter of fact" manner without being antagonistic or confrontational. Something like: "The sudden power loss and reduced speed when power limited mode activates while driving on the highway even when there is plenty of remaining SOC is a safety concern because the car slows down suddenly. Please ask your technicians and Nissan technical support personnel to address this issue."

 

[DaveinOlyWA]

This is also evident in severely diminished DC charging speeds the one time I did a full DC recharge from about 12% to 90% SOC on a 50kW ChargePoint charger. I expected it to hum along at close to 50kW (or whatever the max supported by my 24kWh Leaf) until it got to around 80%, then decrease the power logarithmically-ish until it trickled to full. Instead, it rose to about 35kW for a minute or so, and immediately started the logarithmic-ish throttling as shown below:

Contrast this to when I charge at 6.6kW (from aobut 30% to full) and it follows my expectations:

So this adds to the growing set of evidence that my issue is caused by one or more bad cells. Can't wait to get at this with Leaf Spy Pro.

I've noticed that the car always charges in about 60% of its estimated time. That's also explained by the bad cells' reduced capacity; they fill first spike voltage once full, making the car think it's at full SOC.

Yeah...no. The max is 125 amps. Most stations put out between 118ish to 125 amps. You will see max current to no more than 50% SOC and it will FREQUENTLY be significantly less, as low as 35%. This means a power output maxing around 44-45 KW or so.

Now you will see a slight move to the left on lower power stations that only output 100 amps.

 

[DaveinOlyWA]

This is also evident in severely diminished DC charging speeds the one time I did a full DC recharge from about 12% to 90% SOC on a 50kW ChargePoint charger. I expected it to hum along at close to 50kW (or whatever the max supported by my 24kWh Leaf) until it got to around 80%, then decrease the power logarithmically-ish until it trickled to full. Instead, it rose to about 35kW for a minute or so, and immediately started the logarithmic-ish throttling as shown below:

Contrast this to when I charge at 6.6kW (from aobut 30% to full) and it follows my expectations:

So this adds to the growing set of evidence that my issue is caused by one or more bad cells. Can't wait to get at this with Leaf Spy Pro.

I've noticed that the car always charges in about 60% of its estimated time. That's also explained by the bad cells' reduced capacity; they fill first spike voltage once full, making the car think it's at full SOC.

Yeah...no. The max is 125 amps. Most stations put out between 118ish to 125 amps. You will see max current to no more than 50% SOC and it will FREQUENTLY be significantly less, as low as 35%. This means a power output maxing around 44-45 KW or so.

Now you will see a slight move to the left on lower power stations that only output 100 amps.

 

[twilsonco]

You will see max current to no more than 50% SOC and it will FREQUENTLY be significantly less, as low as 35%.

I assume you mean specifically for the 24kWh battery pack, as the other curves here go well beyond 50% SOC at full charging speed.

 

[DaveinOlyWA]

You will see max current to no more than 50% SOC and it will FREQUENTLY be significantly less, as low as 35%.

I assume you mean specifically for the 24kWh battery pack, as the other curves here go well beyond 50% SOC at full charging speed.

I am not making general comments. This thread does have a topic and its specific to the car.

 

[twilsonco]

Right, sorry. Just making sure.

 

[MikeinPA]

Leaf Spy and a working bluetooth adapter (KONNWEI KW902 for example) will provide a look at individual cell pairs in the pack. Here is recent data from my 2013 which has the "EV system warning light", turtle icon, and P33E6 error code.

(tks leftie)

 

[LeftieBiker]

Upload the image to a service like IMGUR, copy & paste a link to it in a post here, and then highlight the link and select "Img" from the editing tags above the post window.

 

[MikeinPA]

Mods, what about starting a weak cell thread? There are upwards of 500,000 Leafs out there. Most Leafs, like mine, are still be under the 8 year defect in materials and workmanship warranty.

 

[twilsonco]

I get my leaf back tomorrow and have LeafSpy in hand (plus a nifty plotting tool I whipped up in python). I'll share once I've collected and visualized some data.

 

[MikeinPA]

I wish I had the time to learn Python. Looking forward to seeing the app results--excel is not really set up to graph 96 sets of y-axis data.

If you don't have this already, the data in the graph above was collected during Nissan's "Cell Voltage Loss Inspection", see page EVB-160 of the 2013 Leaf EVB manual, here: https://ownersmanuals2.com/d/43004

 

[SageBrush]

If you don't have this already, the data in the graph above was collected during Nissan's "Cell Voltage Loss Inspection", see page EVB-160 of the 2013 Leaf EVB manual, here: https://ownersmanuals2.com/d/43004

Excellent find !

Also worthwhile to read EVB-192

 

[SageBrush]

@GerryAZ,

EVB-192 is pretty clearly a test to evoke a DTC, but it also hides the thresholds. Does a frame freeze (or an alternative method) expose the threshold ?

 

[twilsonco]

the 2013 Leaf EVB manual

edit: nevermind!

Off topic, but I didn't know this existed. Could you provide a list of other such rich documents about the 2013 Leaf?

 

[MikeinPA]

If you don't have this already, the data in the graph above was collected during Nissan's "Cell Voltage Loss Inspection", see page EVB-160 of the 2013 Leaf EVB manual, here: https://ownersmanuals2.com/d/43004

Excellent find !

Also worthwhile to read EVB-192

I can't take credit for finding the manuals, someone else on this forum linked to them with regards to changing a front wheel bearing. Thanks forum!

 

[GerryAZ]

@GerryAZ,

EVB-192 is pretty clearly a test to evoke a DTC, but it also hides the thresholds. Does a frame freeze (or an alternative method) expose the threshold ?

I don't see that the test on page 192 is much of a test. I need to read through the EVB sections in service manuals I have (2011, 2015, and 2019) to see if there are any better descriptions.

 

[nlspace]

Never heard of this--does anyone have a copy of one they could share?

EVB-193
Periodic Maintenance
Inspection

Generation of the EV battery usage report is one of the maintenance items.
This maintenance item generates a report that will help the customer understand the vehicle operating condi- tions needed to keep the Li-ion battery in the best possible condition.
For details about how to generate this report, please refer to EV battery usage report in the CONSULT operation manual.

The low voltage threshold for replacement of a module is 5.0 volts.

 

[twilsonco]

The low voltage threshold for replacement of a module is 5.0 volts.

Could you elaborate a bit on this? You mean if the sun of voltages of the cells in a module is less than 5V, the module is to be replaced?