2019 Leaf battery overheating

Learjet said:

lorenfb said:

Learjet said:

No heat issues charging my 2019 Leaf Plus 62 kwh

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You state that your battery temp stayed the about same. Your battery temp went from about 85F to over 100F,
as indicated by the bar graph, check your video. That's what usually occurs when using L3 versus L1/L2.

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Not sure what you are trying to nit pick...but I clearly showed it increased in the video...and remained at the level even after driving it back home.

Once again my comment was "no heat issues charging my......" I never said it didn't increase....I see no issues with that temp level.

Click to expand...

Consider reading the numerous threads on MNL about how temperature, the result of heat, affects battery degradation
whether it's ambient or internally developed. Remember, Leafs lack a battery TMS like other BEVs, e.g. GM Bolt or Tesla M3.

https://insideevs.com/news/328909/tesla-or-gm-who-has-the-best-battery-thermal-management/

lorenfb said:

Learjet said:

lorenfb said:

You state that your battery temp stayed the about same. Your battery temp went from about 85F to over 100F,
as indicated by the bar graph, check your video. That's what usually occurs when using L3 versus L1/L2.

Click to expand...

Not sure what you are trying to nit pick...but I clearly showed it increased in the video...and remained at the level even after driving it back home.

Once again my comment was "no heat issues charging my......" I never said it didn't increase....I see no issues with that temp level.

Click to expand...

Consider reading the numerous threads on MNL about how temperature, the result of heat, affects battery degradation
whether it's ambient or internally developed. Remember, Leafs lack a battery TMS like other BEVs, e.g. GM Bolt or Tesla M3.

https://insideevs.com/news/328909/tesla-or-gm-who-has-the-best-battery-thermal-management/

Click to expand...

That's ok...I rather enjoy the car than worry too much ....plus... I doubt I will do more than a few quick charges per year...if any...due to my planned use of this car.

Thanks Learjet. For some reason, few of the car reviews/magazines show off the faster charging rate. Given the large number of Leafs going into Norway each month, I am surprised that there are not faster Chademos being installed.

Learjet said:

lorenfb said:

Learjet said:

No heat issues charging my 2019 Leaf Plus 62 kwh

Click to expand...

You state that your battery temp stayed the about same. Your battery temp went from about 85F to over 100F,
as indicated by the bar graph, check your video. That's what usually occurs when using L3 versus L1/L2.

Click to expand...

Not sure what you are trying to nit pick...but I clearly showed it increased in the video...and remained at the level even after driving it back home.

Once again my comment was "no heat issues charging my......" I never said it didn't increase....I see no issues with that temp level.

Click to expand...

Yes one charge at L3 is fine. The issue is the 2nd, 3rd+ L3 charge during the same day on an extended drive.
Always been fine at just one.

Temperature increase was moderate so no problem. Charge rate was similar to my last QC, but tapered a little sooner (probably due to higher ambient temperature for your charge session).

GerryAZ said:

Temperature increase was moderate so no problem. Charge rate was similar to my last QC, but tapered a little sooner (probably due to higher ambient temperature for your charge session).

Click to expand...

here are more details of the event....what stands out to me is the ~28 mins time that this took....seems quick from other videos I have seen....

Start state of charge: 32 %
End state of charge: 81%
Total energy delivered: 25.8 kWh
Max charging rate: 73.13 kW
Charging time: 00:28:29

Learjet said:

GerryAZ said:

Temperature increase was moderate so no problem. Charge rate was similar to my last QC, but tapered a little sooner (probably due to higher ambient temperature for your charge session).

Click to expand...

here are more details of the event....what stands out to me is the ~28 mins time that this took....seems quick from other videos I have seen....

Start state of charge: 32 %
End state of charge: 81%
Total energy delivered: 25.8 kWh
Max charging rate: 73.13 kW
Charging time: 00:28:29

Click to expand...

The faster charge rate is one of THE biggest reasons I wanted the E Plus.

Contrast; yesterday at EVgo,
max rate 120 amps
Ending rate 120 amps
Charge 18-65%
27.65 kwh
time 35:58
Ending batt temps; 75-79º

Cost under COVID discount would have been $7.00 but free to me

lorenfb said:

Consider reading the numerous threads on MNL about how temperature, the result of heat, affects battery degradation
whether it's ambient or internally developed. Remember, Leafs lack a battery TMS like other BEVs, e.g. GM Bolt or Tesla M3.

Click to expand...

Consider your usage and your climate.

Unless you plan on many DCQCs in a hot climate, or live in a very hot climate, a TMS doesn't have a strong impact on battery life. Long trips at high speed involving many DCQC sessions per day will have much slower charge rates.

Also consider the advantages of not having a TMS. The car is simpler, more reliable and far less likely to catch fire.

Learjet said:

lorenfb said:

Learjet said:

No heat issues charging my 2019 Leaf Plus 62 kwh

Click to expand...

You state that your battery temp stayed the about same. Your battery temp went from about 85F to over 100F,
as indicated by the bar graph, check your video. That's what usually occurs when using L3 versus L1/L2.

Click to expand...

Not sure what you are trying to nit pick...but I clearly showed it increased in the video...and remained at the level even after driving it back home.

Once again my comment was "no heat issues charging my......" I never said it didn't increase....I see no issues with that temp level.

Click to expand...

Start at 2:23 of your video. You said, "battery temperature is hanging in there, hasn't creeped up any higher."

It did increased one bar from when you started charging and that's why lorenfb stated that. Sorry for nit picking.

Hi guys,

since the prices for used electric cars go down nicely, I am deciding between Nissan Leaf 2019 and e-Golf 2019.

I did read about Rapidgate but isn't it the same problem with Golf since the battery is not actively cooled either?

I'd love to buy this one https://elektromobilne.cz/nissan-leaf-jako-dospely-elektromobil/ because of the 7,9 secs acceleration but wouldn't it be more reasonable to go for more reliable rapid charging in case the e-Golf doesn't have these problems?

Does it? There is no mention on the internet about similar problem with Golf, could it be the engine sucks just 100 kW and the acceleration is slower by almost two seconds - and / or better charging management?

Thanks for any hints on that matter. I'd love to buy Leaf but also I have to be able to travel and charge in reasonable time.

Most of us with Plus models never hit the thermal limitations, as it usually required driving more than 2 full charges in a day with minimal breaks, or over 400 miles. I have done over 500 (with a visit with a friend in the middle) without hitting any throttling.

It does appear that the new Leaf battery (+) deals with heat better, but that said, you can throttle if doing extended driving in hot weather).

DougWantsALeaf said:

It does appear that the new Leaf battery (+) deals with heat better,

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Anecdotal! You can still "cook" the Leaf battery on a hot day (>80F) driving at high speeds. QC charging the Leaf is not its only heat related problem,
whether the Leaf2 has a 40kWh or a 60kWh battery.

lorenfb said:

Anecdotal! You can still "cook" the Leaf battery on a hot day (>80F) driving at high speeds. QC charging the Leaf is not its only heat related problem,
whether the Leaf2 has a 40kWh or a 60kWh battery.

Click to expand...

Anything is possible, but in the case it is unlikely, and the lack of anecdotal reports from owners world-wide seems to support that.

lorenfb said:

DougWantsALeaf said:

It does appear that the new Leaf battery (+) deals with heat better,

Click to expand...

Anecdotal! You can still "cook" the Leaf battery on a hot day (>80F) driving at high speeds. QC charging the Leaf is not its only heat related problem,
whether the Leaf2 has a 40kWh or a 60kWh battery.

Click to expand...

I am not sure what you mean--QC will heat the battery, but air flow around the battery compartment during highway driving actually cools the battery (2011, 2015, and 2019 all exhibited this when monitoring the battery temperature with Leaf Spy). It is rare to see the temperature bar display drop from highway driving unless the battery is really hot after QC, but it is possible to have enough cooling to see the temperature display in the dash drop. During the summer, I usually see battery temperature (as indicated by Leaf Spy) increase during city driving after getting off the freeway and cool down slightly if I get back on the freeway.

FWIW, the 2019 battery seems to run cooler than the 2015 did when new and the 2015 ran cooler than the 2011 battery in my climate.

GerryAZ are you still seeing 97% SOH?

lorenfb said:

DougWantsALeaf said:

It does appear that the new Leaf battery (+) deals with heat better,

Click to expand...

Anecdotal! You can still "cook" the Leaf battery on a hot day (>80F) driving at high speeds. QC charging the Leaf is not its only heat related problem,
whether the Leaf2 has a 40kWh or a 60kWh battery.

Click to expand...

Work at it hard enough and I am sure you can figure out a way to get it done.

GerryAZ said:

I am not sure what you mean--QC will heat the battery, but air flow around the battery compartment during highway driving actually cools the battery

Click to expand...

You're joking, right? Describe the air flow around the battery. The battery is basically thermally isolated from ambient which results
in its having a long thermal constant, i.e. to heat-up or cool down from ambient effects. Since high speed driving develops heat quickly
from the I^2*R heating from the motor current, the battery will heat up fairly quickly as in QCing. With regard to QCing, do you fail to
understand the I^2 * R heating effect from a high charging current that affects battery degradation, and why "throttling" occurs?
So given the fairly long thermal time constant for cooling, the Leaf battery "cooks" the result of excessive QCing/high speed driving,
versus a BEV with TMS.

GerryAZ said:

It is rare to see the temperature bar display drop from highway driving unless the battery is really hot after QC, but it is possible to have enough cooling to see the temperature display in the dash drop. During the summer, I usually see battery temperature (as indicated by Leaf Spy) increase during city driving after getting off the freeway and cool down slightly if I get back on the freeway.

Click to expand...

And what's the conclusion, if there's any?

lorenfb said:

GerryAZ said:

I am not sure what you mean--QC will heat the battery, but air flow around the battery compartment during highway driving actually cools the battery

Click to expand...

You're joking, right? Describe the air flow around the battery. The battery is basically thermally isolated from ambient which results
in its having a long thermal constant, i.e. to heat-up or cool down from ambient effects. Since high speed driving develops heat quickly
from the I^2*R heating from the motor current, the battery will heat up fairly quickly as in QCing. With regard to QCing, do you fail to
understand the I^2 * R heating effect from a high charging current that affects battery degradation, and why "throttling" occurs?
So given the fairly long thermal time constant for cooling, the Leaf battery "cooks" the result of excessive QCing/high speed driving,
versus a BEV with TMS.

Click to expand...

I am serious--air flow over the battery case at highway speeds will dissipate some of the heat and reduce the temperature displayed by Leaf Spy if the battery is significantly hotter than ambient (such as from QC). Since power required to maintain highway speed is much less than QC charging, the discharge current is not high and the internal I^2*R losses (and hence heat generated) are low. The internal resistance of new (not significantly degraded) LEAF batteries is quite low. The internal resistance increases as the batteries deteriorate so 8-capacity-bar batteries will generate more heat during discharge from highway driving (and especially from QC charging) than 12-bar batteries, but the internal resistance of even an 8-bar battery is still relatively low.

If the battery is cool, then highway driving will increase battery temperature until it reaches an equilibrium temperature enough higher than ambient to cause heat transfer through the thermal resistance(s) between the cells and ambient equal to the heat generated internally. The battery cells together make a large thermal mass so that large mass heats and cools slowly, but the heat transfer is dependent upon the temperature differential between the cells and ambient. In normal day-to-day driving, the battery will cool while the car is parked overnight, but battery temperature will ratchet up during a long trip with multiple QC's because more heat is generated during each QC than dissipated by driving between QC's.

There is plenty of anecdotal evidence that with the Gen I Leaf, at least, highway driving after heating the battery with a QC will cool the battery somewhat. The airflow space present above the battery in the Gen I is essentially nonexistent above the battery in the 40+kwh cars, but that still leaves the underside to dissipate heat to the air stream.

LeftieBiker said:

There is plenty of anecdotal evidence that with the Gen I Leaf, at least, highway driving after heating the battery with a QC will cool the battery somewhat. The airflow space present above the battery in the Gen I is essentially nonexistent above the battery in the 40+kwh cars, but that still leaves the underside to dissipate heat to the air stream.

Click to expand...

Maybe. I found that to be rather inconsistent. The issue is cooler weather usually means wetter roads, less efficiency, higher power output.

But I have also noticed a difference even between the 40 and 62 kwh packs. The Plus packs simply stay cooler. Whether the extra cell count makes that much of a difference or that some sort of ventilation has been added or simply what was "high" power in smaller packs is simply not in the larger packs.

Guessing its a combination of all those things. FYI; a very reputable dealer in the Seattle area let it slip that the plus packs had cooling. When asked for details he clammed up. He is privy to considerably more information than most LEAF salesmen due to his status in the company ( 3X NA #1 LEAF sales) So a slip of the tongue?

Knowing him personally, I would find it hard to believe he made the comment to generate sales.