metricus
Posts: 94
Joined: Wed May 15, 2019 1:51 pm
Delivery Date: 28 Apr 2019
Leaf Number: 307046
Location: Reading, PA

Re: 2019 Leaf battery overheating

Sun May 19, 2019 6:21 am

SageBrush wrote:That said, should Nissan have disclosed rapid-gate ? Obviously. But even then it is complicated. Rapid gate at what ambient temperature ? At what driving speed ? In what terrain ? With how many passengers ? I think they should provide a table that shows DCFC speeds by battery temperature but between you and me, how useful would that be to Joe consumer ? Or to you, for that matter ?


You are correct. My frustration is that even at mild temperatures the Leaf is throttling down the charge speed and I am sure that the average Joe consumer would be pissed about this. This did not happen to the 2016 Leaf.

Here is another test I did yesterday:

So outside temperatures were mild 25C. We took a trip to KOP Mall wich is a light ride for the 40 kWh leaf. My battery temp stayed all day smack in the middle. (i don't have the Leaf Spy adapter yet so just bear with me).

On my way back i stopped at the last plaza on the Turnpike before my exit to test the charge. I was at 26% at the time enough to get me home. Right of the bat the charge got throttled down to 32kW. No Idea why. I had done nothing weird. i drove under speed limit. The car had been parked underground at the Mall the whole time.

I have NCTC so I said what the heck lets put some free juice... So I left it for about 20 mins or so.

The temp got up 2 notches very short after initiating charge 5-10 mins. (there are 4 stages/notches between middle and first red line) So the temp was at what i would call 3/4 during charge and the power stayed at 32kW all the time. After 20 min, the charge got up to 64% so I said let's try something new:

So I stopped charging unplugged and then started a fresh new charge. Guess what? the new charge was throttled down to 22kW. Let's be clear: It was 32 when I unplugged and the charge level was way before it throttles down for being full.

So the computer saw the temp was high at 3/4 and decided to throttle me down even though, had I left it alone, it would have continued at 32.

In other words the charge power is determined at the beginning of the charge based on the temp at that moment and kept constant throughout the charge independent of temp rise. Only the charge level throttles down the power during a charge.

DaveinOlyWA
Posts: 13847
Joined: Sat Apr 24, 2010 7:43 pm
Delivery Date: 16 Feb 2018
Leaf Number: 314199
Location: Olympia, WA
Contact: Website

Re: 2019 Leaf battery overheating

Sun May 19, 2019 6:36 am

metricus wrote:
SageBrush wrote:That said, should Nissan have disclosed rapid-gate ? Obviously. But even then it is complicated. Rapid gate at what ambient temperature ? At what driving speed ? In what terrain ? With how many passengers ? I think they should provide a table that shows DCFC speeds by battery temperature but between you and me, how useful would that be to Joe consumer ? Or to you, for that matter ?


You are correct. My frustration is that even at mild temperatures the Leaf is throttling down the charge speed and I am sure that the average Joe consumer would be pissed about this. This did not happen to the 2016 Leaf.

Here is another test I did yesterday:

So outside temperatures were mild 25C. We took a trip to KOP Mall wich is a light ride for the 40 kWh leaf. My battery temp stayed all day smack in the middle. (i don't have the Leaf Spy adapter yet so just bear with me).

On my way back i stopped at the last plaza on the Turnpike before my exit to test the charge. I was at 26% at the time enough to get me home. Right of the bat the charge got throttled down to 32kW. No Idea why. I had done nothing weird. i drove under speed limit. The car had been parked underground at the Mall the whole time.

I have NCTC so I said what the heck lets put some free juice... So I left it for about 20 mins or so.

The temp got up 2 notches very short after initiating charge 5-10 mins. (there are 4 stages/notches between middle and first red line) So the temp was at what i would call 3/4 during charge and the power stayed at 32kW all the time. After 20 min, the charge got up to 64% so I said let's try something new:

So I stopped charging unplugged and then started a fresh new charge. Guess what? the new charge was throttled down to 22kW. Let's be clear: It was 32 when I unplugged and the charge level was way before it throttles down for being full.

So the computer saw the temp was high at 3/4 and decided to throttle me down even though, had I left it alone, it would have continued at 32.

In other words the charge power is determined at the beginning of the charge based on the temp at that moment and kept constant throughout the charge independent of temp rise. Only the charge level throttles down the power during a charge.


Your test was "normal"... or rather "expected"

https://daveinolywa.blogspot.com/2018/1 ... -leaf.html

There are a few things to look at here.

RapidGate; Reduction of max charge speed due to "starting" temperature of the batteries. This is what you saw on your 2nd charge session.


The pack's optimum starting temperature for a QC is about 86º more or less. This enables the highest knee (knee is the SOC when the current starts to drop.) Colder than that, your knee drops. Warmer than that; you don't get max current at the beginning of the charge.
2011 SL; 44,598 miles. 2013 S; 44,840 miles.2016 S30 deceased. 29,413 miles. 2018 S40; 15,000 miles, 478 GIDs, 37.0 kwh 109.81 Ahr , SOH 94.61, Hx 120.15
My Blog; http://daveinolywa.blogspot.com" onclick="window.open(this.href);return false;

metricus
Posts: 94
Joined: Wed May 15, 2019 1:51 pm
Delivery Date: 28 Apr 2019
Leaf Number: 307046
Location: Reading, PA

Re: 2019 Leaf battery overheating

Sun May 19, 2019 6:39 am

What i forgot to say in the previous story is that the battery stayed at 3/4 all the way home. 3 hours later the temp had dropped to on notch over the middle. Only this morning its at middle again. Car is garaged if you ask.

In my view this is not a usable vehicle. It's like an ICE car would start blowing steam through the radiator's saftey valve every 200 miles and the only way to continue your trip was to let it cool overnight. This vehicle is useless to the average Joe consumer. I could live with it for the 2 year lease term but it is a major pain in the rear.

These are moments when I congratulate myself for only leasing these new tech vehicles. You REALLY never know if your car will end up with a lemon reputation and nobody wants to buy it used.

metricus
Posts: 94
Joined: Wed May 15, 2019 1:51 pm
Delivery Date: 28 Apr 2019
Leaf Number: 307046
Location: Reading, PA

Re: 2019 Leaf battery overheating

Sun May 19, 2019 6:44 am

DaveinOlyWA wrote:Your test was "normal"... or rather "expected"

https://daveinolywa.blogspot.com/2018/1 ... -leaf.html

There are a few things to look at here.

RapidGate; Reduction of max charge speed due to "starting" temperature of the batteries. This is what you saw on your 2nd charge session.

The pack's optimum starting temperature for a QC is about 86º more or less. This enables the highest knee (knee is the SOC when the current starts to drop.) Colder than that, your knee drops. Warmer than that; you don't get max current at the beginning of the charge.


Thank you. Very pertinent info. I really appreciate.

Which brings us to the conclusion that NISSAN is guilty of false advertisement. I smell a class action here....

SageBrush
Posts: 4100
Joined: Sun Mar 06, 2011 2:28 am
Delivery Date: 13 Feb 2017
Location: Colorado

Re: 2019 Leaf battery overheating

Sun May 19, 2019 6:57 am

metricus wrote:In other words the charge power is determined at the beginning of the charge based on the temp at that moment and kept constant throughout the charge independent of temp rise. Only the charge level throttles down the power during a charge.

Yep.

You are discovering what has been known for well over a year. TeslaBjorn published a video on his youtube channel that has a table showing the charge rate by starting temperature.

I'm not trying to berate you but I am surprised that this information is new to you. I thought rapid-gate had reached the general media and it has been discussed ad-nausea on this forum.

Addendum:
A google search for rapidgate brought up this
https://news.google.com/search?q=nissan ... id=US%3Aen
So extensively reported in the EV centric media, some mention in the general car media. I didn't see mention in the media outlets with the largest readerships.
2013 LEAF 'S' Model with QC & rear-view camera
Bought off-lease Jan 2017 from N. California
Car is now enjoying an easy life in Colorado
03/2018: 58 Ahr, 28k miles
11/2018: 56.16 Ahr, 30k miles
-----
2018 Tesla Model 3 LR, Delivered 6/2018

metricus
Posts: 94
Joined: Wed May 15, 2019 1:51 pm
Delivery Date: 28 Apr 2019
Leaf Number: 307046
Location: Reading, PA

Re: 2019 Leaf battery overheating

Sun May 19, 2019 7:06 am

Like I said in my very first post: I was a happy customer with my 2016-24kwh. I never had to Google my car.
I really thought they had worked-out the bugs.

The issue I have it's not that it is throttled but that they do it at mild temps. I would understand having such problems in Nevada but not in springtime PA.

SageBrush
Posts: 4100
Joined: Sun Mar 06, 2011 2:28 am
Delivery Date: 13 Feb 2017
Location: Colorado

Re: 2019 Leaf battery overheating

Sun May 19, 2019 7:08 am

metricus wrote:In my view this is not a usable vehicle..

Sure it is, but it is not a full replacement for a general purpose car like an ICE or a Tesla.

As a longish range commuter ( ~ 100 miles between charges when new) car it is fully functional.
We agree that in no reasonable way should it be viewed as a long distance car via DC fast charging.

Let me repeat my first response, back on page #1
The LEAF is a ( hobbled, at that) one DCFC per trip car.
If your use case is more than that you leased the wrong car.


The 62 kWh model is improved in terms of rapid-gate but it STILL not a general purpose car replacement. No EV is without a proper TMS.
Last edited by SageBrush on Sun May 19, 2019 7:25 am, edited 3 times in total.
2013 LEAF 'S' Model with QC & rear-view camera
Bought off-lease Jan 2017 from N. California
Car is now enjoying an easy life in Colorado
03/2018: 58 Ahr, 28k miles
11/2018: 56.16 Ahr, 30k miles
-----
2018 Tesla Model 3 LR, Delivered 6/2018

SageBrush
Posts: 4100
Joined: Sun Mar 06, 2011 2:28 am
Delivery Date: 13 Feb 2017
Location: Colorado

Re: 2019 Leaf battery overheating

Sun May 19, 2019 7:12 am

metricus wrote:Like I said in my very first post: I was a happy customer with my 2016-24kwh. .

The 40 kWh LEAF will be every bit as functional as the 24 kWh model, and more.

You will have to dial down your expectations to something closer to the 24 kWh model.
2013 LEAF 'S' Model with QC & rear-view camera
Bought off-lease Jan 2017 from N. California
Car is now enjoying an easy life in Colorado
03/2018: 58 Ahr, 28k miles
11/2018: 56.16 Ahr, 30k miles
-----
2018 Tesla Model 3 LR, Delivered 6/2018

metricus
Posts: 94
Joined: Wed May 15, 2019 1:51 pm
Delivery Date: 28 Apr 2019
Leaf Number: 307046
Location: Reading, PA

Re: 2019 Leaf battery overheating

Sun May 19, 2019 7:20 am

SageBrush wrote:You will have to dial down your expectations to something closer to the 24 kWh model.


Big disappointment in other words.

I never saw my battery temp going up during QC. I definitely did not have this problem. My only problem was not having enough range to reach chargers in certain directions. On other routes I had, and at one point was doing regular trips to Philly twice a week with repeated QC. Never saw the gauge go up, never had the speed throttled down.

To me it was just like a smartphone....

SageBrush
Posts: 4100
Joined: Sun Mar 06, 2011 2:28 am
Delivery Date: 13 Feb 2017
Location: Colorado

Re: 2019 Leaf battery overheating

Sun May 19, 2019 7:37 am

metricus wrote:I never saw my battery temp going up during QC.

That is probably just an artefact of the crappy temperature gauges Nissan displays. As you have been advised, get LeafSpy if you want to know battery temperatures. Is your battery heating up faster than expected ? I'm not sure; you would have to do better testing. For a start, you could calculate the battery resistance. Here is a tutorial: https://batteryuniversity.com/learn/art ... resistance

The general consensus around here is that the 40 kWh LEAF battery temperature does not rise any faster than prior generations but it is slower to cool off. I think this just reflects the higher mass of the 40 kWh battery.
Last edited by SageBrush on Sun May 19, 2019 8:08 am, edited 1 time in total.
2013 LEAF 'S' Model with QC & rear-view camera
Bought off-lease Jan 2017 from N. California
Car is now enjoying an easy life in Colorado
03/2018: 58 Ahr, 28k miles
11/2018: 56.16 Ahr, 30k miles
-----
2018 Tesla Model 3 LR, Delivered 6/2018

Return to “Batteries & Charging”