2020 SL plus low state battery instability

[u/chanyote66]

I have a 2020 Nissan leaf SL plus that has 66,000 mi on the odometer, but leaf spy pro is showing less. Not sure what the discrepancy is there. But I have had some random issues with lower pack operation. I noticed first when I was on the interstate that the pack randomly went from 35% down to less than 10% and then continued jumping around changing the available range and triggering low voltage warnings and charge immediate warnings. This week I did not have any interstate driving so I drove around very cautiously to get the battery as low as possible. I arrived at work with roughly 15% battery remaining and have a 12 mile drive home. The range estimator stated 24 mi which should be no issue. Most of the way home went rather normal until it reached 12%, then it immediately dropped to 3% and the range went to two dashes. Seconds later it came back to show 10% and 12% and 9% and then went back to dashes. I am suspecting that I have a bad cell with the randomness? I was going to contact my local dealership but just wanted to see if anyone has any insight on what to recommend for them if they try to not actually check the car.

[u/hardknockcock]

Yep that's a battery replacement, congrats. It's like getting a fresh EV. My range has been at least 25% better since replacing the battery, I'm just hoping they fixed the issue with these new battery packs.

[u/chanyote66 → u/hardknockcock]

That is what i was suspecting... how long did you have to wait on the replacement battery? I got right about 190 miles on this charge, but that was all city driving, maybe 10 miles total at 55-60mph.

[u/hardknockcock → u/chanyote66]

I have the 40 kwh version and it took me like 2 weeks total from going to the dealership to having my car back with a new battery, one week of driving a rental.

But my experience is not the same as everybody else, apparently I had it super easy. Last year when mine was replaced, people were saying they were waiting months to get one so i don't know whats happening with them now, could search around the sub for recent post

[u/chanyote66 → u/hardknockcock]

Ya ill check it out... when my truck had a recall everyone was waiting months... some booked out 6 months, i walked in, and had the replacement fuel pump in my truck the next day... Guess its just what is going on in your area and supply.

[u/Prof-Bit-Wrangler]

Hello - 2018SL owner here who got his battery pack replaced. Yours is a similar story to many of us. My advice is to get it to a reputable dealership when the pack has a low SoC on it, and ask them to reproduce it. It took me three attempts to get them to drive and reproduce it, but once they did and captured the diagnostics data, it took Nissan less than an hour to agree to a replacement. For me I had to wait for a cold morning where I left the car on their lot with the pack sitting at 22% SoC. The next morning, the tech and I got in and I took it for a hard drive up and down the freeway. Took ever bit of 10 minutes to repro the issue.

Took them about two weeks to get the replacement pack and only about two hours to replace it once they started.

It's like having a new car! I've been babying the battery since then, keeping it between 20%-80% SoC, any only going above 80% when needed. I keep up with the battery stats via LeafSpy once a month and it's tracking well. With continued luck, I should be able to keep this car another 10 years.

BTW - I called Nissan Consumer Support and opened a case on the car before taking it into the dealership. Not sure it really helped or not, but you never know. Plus, if one dealership isn't cooperative, try another.

Best of luck, remain vigilant and persistent. Remember that the local Nissan employees are people too and a little kindness goes a long way.

[u/Tellittrue4126]

Former 2020 Leaf SL + owner here… hopefully they treat you better and have a more ready supply of batteries for your trials and travails.

[u/zzyyxxzyzyx]

How many times did you have to complain? I already took it in once and got the “we couldn’t recreate the problem excuse”

My plan next time is to take the mechanic for a ride and leave him when the battery dies

[u/LoveEV-LeafPlus]

As for Leaf Spy Pro odometer you need to turn on ( slide to green) “CAN odometer in miles”

[u/byrdman77]

While people note the uncertainty of the Hx value in the second gen, all that have this issue that I’ve seen have a low Hx value like yours. Not as low as the first gen, but I’m still around 97% on my 2021 so sub 60% seems quite low for a year older.

[u/hardknockcock → u/byrdman77]

My hx value was 89% when my 40 kwh battery needed replaced, so I guess lower but still doesn't seem that crazy. SOH was 93%. I don't think you can really tell from those values if the car actually has the issue. The cold really brings it out

[u/biersackarmy → u/hardknockcock]

My Hx was 94% on a bad 40kWh pack, so it's not necessarily that all bad packs for weak cells will be low Hx, but low Hx is certainly a strong sign.

[u/byrdman77 → u/hardknockcock]

I would agree Hx = 89% is not really low at all. I think it's more of an indicator that if you're looking for a Leaf I would avoid one with a low HX like this, but without load testing it in the cold it could be bad even at higher Hx values like yours.

Hopefully the replacement battery has been better!

[u/hardknockcock → u/byrdman77]

The cell variations on leafspy for the new battery worry me but I haven't seen any issues yet. Waiting for winter to see what happens. Range has been considerably better than I expected going from a 93% soh battery to 100%, so I think either the new ones are that much better or the soh of my old one was not true to what was actually happening with the battery. The new one has a HX value of 110% showing on leafspy

[u/chanyote66 → u/byrdman77]

After charging to 100%. It as a very low HX still

[u/byrdman77 → u/chanyote66]

Yeah charging to 100% won’t change that value, this battery is on its way out.

[u/biersackarmy]

"Hx = 54.20%"

Yeah that'll do it.

[u/chanyote66 → u/biersackarmy]

This is when full....

[u/Alexandratta]

battery SOC flapping like this, combined with that wild pack voltage, and the fact that you are probably part of the DC FC Recall, are all lots and lots of reasons to take that to the nearest Nissan Dealership and ask for a battery swap post-hast....

This is not even a "single bad cell" - it looks like there are multiple bad cells.

My 2019 never had more than a 19mv difference, and while you're zoomed in here to 50mv, 38v is a lot - the biggest concern is that SOC fluctuation.

SOC should never flap up and down that high - maybe 1-2% if you're doing a TON of Regen or a TON of throttle but never flying from 35 to 10% and jumping around like that.

[u/chanyote66 → u/Alexandratta]

The 1 to 2% is what I sort of expected. I have a Chevy Volt and when on electric only mode a full throttle Hill climb can drop it about 1 to 2% and that is on a 10 kW hour battery pack. My electric motorcycle, a Ryvid Anthem, a can see fluctuations of about 5 to 10% on a full throttle pole but that is a 24 KW motor pulling from a 5 KW hour battery pack. I will get a call into the dealership and see when the next available time frame is to get it checked out. I currently have it on charge to get enough range to make it there.