2020 Leaf SV going bad at 32k miles?

[StillyOKevGuy]

First time EV owner here. Recently(less than a week)I bought a used 2020 Leaf SV, 40kwh battery from Carvana. I first got the feeling something was up when the day I got the car I tested the acceleration and it almost immediately went into Turtle Mode at around 75% battery. Nothing else seemed wrong and by the next day it was out of turtle mode and seemed normal. Then on my drive to work(highway speeds, 25 miles 1 way, 33°F-40°F outside temps) these past 2 days whenever I need to give the car more acceleration I.E going up a hill or the cruise control maintaining speed, the battery % starts fluctuating like crazy, going all the way down almost to 0 and anywhere in between 0 and whatever the battery was before it started(Plugged in the night before and started at 100% both days, and problems happen around 80%-75%).
Is my battery or a few of its cells toast? I've got an OBD2 meter coming in the mail so I can check myself but I'm curious if this problem is common or not

 

[Stanton]

Is my battery or a few of its cells toast? I've got an OBD2 meter coming in the mail so I can check myself but I'm curious if this problem is common or not

Yes.
I would never buy a used Leaf without taking a LeafSpy reading (cell pair voltages). Preferable to do it at <50% SOC, although it sounds like this car has trouble even above that; previous owner probably sold it in frustration.

 

[StillyOKevGuy]

Yes.
I would never buy a used Leaf without taking a LeafSpy reading (cell pair voltages). Preferable to do it at <50% SOC, although it sounds like this car has trouble even above that; previous owner probably sold it in frustration.

I've attached a screenshot of my cell pair voltages after getting my OBD2 reader. So from what I've read, I know this most likely is bad. I could do with a better explanation of why it is bad however

 

[Snakebitten]

On your graph you are looking for the delta (difference) between your weakest and strongest cells.
Your screenshot is missing the delta in millivolts.

Here is my 2018 Leaf delta at a 38% SOC. It's 17 millivolts, which is why the graph shows a small variance overall.



At higher SOC you should see even less variance.
6 millivolts at 95% SOC




When I was shopping for a depreciated, but well kept Leaf, my test drive was really sitting parked in the dealership lot looking at this LeafSpy screen.

 

[Drew21]

Does Carvana have any kind of warranty or quality guarantee? I would be looking into that ASAP.

 

[Stanton]

I've attached a screenshot of my cell pair voltages after getting my OBD2 reader. So from what I've read, I know this most likely is bad. I could do with a better explanation of why it is bad however

Why is it bad?
A ~200mV delta is bad at any SOC, but in this case you haven't even fallen below 50% SOC (so it may get worse). In addition, it looks as though you have at least (2) weak/bad cells, which are (unfortunately) spread across (2) different modules, so you have to factor that into your hardware/cost estimates.
Sorry to be the bearer of bad news.

 

[Mcflocki]

At least the vehicle is under warranty. The good news is the vehicle may end up getting a new battery under warranty. The bad news is that it’s a long sometimes difficult and frustrating process. The dealer won’t do anything until the car give the right fault code unless you have video evidence and it’s reproducible under their inspection and test drive. The code will only trigger under certain conditions but basically you’re going to need to push the car in extreme conditions to get the code unless the battery is really bad. Some of the codes clear themselves when you turn the car off and on. Sometimes the codes you get disable the car from driving. Sometimes you can limp it to the dealership with the code and sometimes you need to get a tow truck to take you there. Sometimes the dealer gives a loaner but sometimes they won’t. The wait for a new battery and the install is sometimes long.

 

[knightmb]

I've attached a screenshot of my cell pair voltages after getting my OBD2 reader. So from what I've read, I know this most likely is bad. I could do with a better explanation of why it is bad however

Bad news, you certainly have an issue. Good news, if the mileage is low enough, you can get a battery replacement. The other Bad news is that you will need to make a lot preparations for this. This includes documenting every issue as it happens and giving good detail about what happens as per your post above "I tested the acceleration and it almost immediately went into Turtle Mode at around 75% battery", document when it happens, date and time. Next, find out what Nissan dealership near you has certified Leaf Techs on staff. Read some online reviews about them to determine if they are shady or friendly. Finally, find a way to trigger some dash codes. Easier in cold weather. Try to time it so they trigger near the dealership you want to bring your Leaf so the tech can see the codes in real-time. Heck, don't even turn off the Leaf at the dealership, they can connect their equipment to get a diagnostic in real-time with it still on.

Triggering a code may not be necessary if you can get it to trigger turtle mode and drive to the dealership like that. Be sure it was on a high SOC so they won't give you the lame excuse "well, you just need to charge it up". Also, don't say anything about LeafSpy, be sure you remove your blue-tooth OBDII device, etc. Don't come at the dealership staff like a tech wizard because it will just make them give you the evil eye, they aren't technical. When the Leaf tech comes to talk to you, then lay on the expertise.

Talk about battery warranty and wanting an immediate fix. Be sure they give you everything in documentation for later that you file away for when you have to talk to Nissan consumer people about the battery warranty. You have a long road ahead of you, but if you really want to keep your Leaf and basically give it double the life with a new battery, many on this forum have done it.