cwerdna
Posts: 9676
Joined: Fri Jun 03, 2011 4:31 pm
Delivery Date: 28 Jul 2013
Location: SF Bay Area, CA

Re: 2019 Leaf battery overheating

Fri May 17, 2019 11:17 am

DaveinOlyWA wrote:
cwerdna wrote:Out of curiosity, is this a 40 kWh car or a 62 kWh Leaf Plus?

Many other EVs have active thermal management... Bolt does but its DC FCing isn't that fast (from what I hear). In the case of https://electricrevs.com/2018/07/17/wat ... -to-55-kw/, it may start slowing down after 55% SoC. And, I hear it's quite slow if the battery's cold, until it warms up enough.
In a race with the Bolt, 30 kwh LEAF and 40 kwh LEAF, who would win?

Winner; 30 kwh LEAF simply because of its ability to charge at full speed to 80% SOC. Test based on 5 mins plus charge time for each QC stop. There were parameters for trip length with Bolt and 40 having advantage in shorter distances due to higher range which was GREATLY mitigated if all cars started race at 50% SOC.

FYI; The 30 wins barely if the race is long enough BUT the 40 loses badly in anything over 300 miles or so.

But the main advantage of having a bigger pack is simply more charging options convenient to personal needs (which often do not follow a schedule) and the ability to charge the lower 2/3rds of the pack (something Bolt excels) which helps to slow temperature rise.
You think so?

With a sufficiently powerful DC FC. I think the Bolt would win if you only started charging the Bolt when nearly empty and cut it off at when it starts throttling down or starts becoming slower than that 30 kWh Leaf. In https://electricrevs.com/2018/07/17/wat ... -to-55-kw/, during his testing, it dropped below 54 kW charging rate once he passed 54% SoC. Was full power up until that point.

Also, if you started with a full charge on each, the Bolt would go about 2x as far as the 30 kWh Leaf on the initial charge. And, if you did multiple DC FCs in a day, I bet that 30 kWh battery would overheat and throttling might begin sooner whereas Bolt has battery thermal management.

edit: In Jeff's test, from about 54% to about 70%, he was maintaining 38+ kW charging rate. Then it sharply dropped off to about 23 to 24-ish kW.
Last edited by cwerdna on Fri May 17, 2019 12:50 pm, edited 1 time in total.

'19 Bolt Premier
'13 Leaf SV w/premium package (owned)
'13 Leaf SV w/QC + LED & premium packages (lease over, car returned)

Please don't PM me with Leaf questions. Just post in the topic that seems most appropriate.

Astros
Posts: 113
Joined: Wed Oct 11, 2017 11:21 am
Delivery Date: 28 Apr 2018
Leaf Number: 310136
Location: Seattle, WA

Re: 2019 Leaf battery overheating

Fri May 17, 2019 12:29 pm

cwerdna wrote:
DaveinOlyWA wrote:
cwerdna wrote:Out of curiosity, is this a 40 kWh car or a 62 kWh Leaf Plus?

Many other EVs have active thermal management... Bolt does but its DC FCing isn't that fast (from what I hear). In the case of https://electricrevs.com/2018/07/17/wat ... -to-55-kw/, it may start slowing down after 55% SoC. And, I hear it's quite slow if the battery's cold, until it warms up enough.
In a race with the Bolt, 30 kwh LEAF and 40 kwh LEAF, who would win?

Winner; 30 kwh LEAF simply because of its ability to charge at full speed to 80% SOC. Test based on 5 mins plus charge time for each QC stop. There were parameters for trip length with Bolt and 40 having advantage in shorter distances due to higher range which was GREATLY mitigated if all cars started race at 50% SOC.

FYI; The 30 wins barely if the race is long enough BUT the 40 loses badly in anything over 300 miles or so.

But the main advantage of having a bigger pack is simply more charging options convenient to personal needs (which often do not follow a schedule) and the ability to charge the lower 2/3rds of the pack (something Bolt excels) which helps to slow temperature rise.
You think so?

With a sufficiently powerful DC FC. I think the Bolt would win if you only started charging the Bolt when nearly empty and cut it off at when it starts throttling down or starts becoming slower than that 30 kWh Leaf. In https://electricrevs.com/2018/07/17/wat ... -to-55-kw/, during his testing, it dropped below 54 kW charging rate once he passed 54% SoC. Was full power up until that point.

Also, if you started with a full charge on each, the Bolt would go about 2x as far as the 30 kWh Leaf on the initial charge. And, if you did multiple DC FCs in a day, I bet that 30 kWh battery would overheat and throttling might begin sooner whereas Bolt has battery thermal management.
The Bolt would easily win over 300 miles, at least in part due to its' higher overall efficiency. It would even narrowly beat the Leaf Plus, though maybe not if there was a 100kW charger available.
2019 Deep Blue SL Plus

DaveinOlyWA
Posts: 14107
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

Fri May 17, 2019 1:37 pm

cwerdna wrote:
DaveinOlyWA wrote:
cwerdna wrote:Out of curiosity, is this a 40 kWh car or a 62 kWh Leaf Plus?

Many other EVs have active thermal management... Bolt does but its DC FCing isn't that fast (from what I hear). In the case of https://electricrevs.com/2018/07/17/wat ... -to-55-kw/, it may start slowing down after 55% SoC. And, I hear it's quite slow if the battery's cold, until it warms up enough.
In a race with the Bolt, 30 kwh LEAF and 40 kwh LEAF, who would win?

Winner; 30 kwh LEAF simply because of its ability to charge at full speed to 80% SOC. Test based on 5 mins plus charge time for each QC stop. There were parameters for trip length with Bolt and 40 having advantage in shorter distances due to higher range which was GREATLY mitigated if all cars started race at 50% SOC.

FYI; The 30 wins barely if the race is long enough BUT the 40 loses badly in anything over 300 miles or so.

But the main advantage of having a bigger pack is simply more charging options convenient to personal needs (which often do not follow a schedule) and the ability to charge the lower 2/3rds of the pack (something Bolt excels) which helps to slow temperature rise.
You think so?

With a sufficiently powerful DC FC. I think the Bolt would win if you only started charging the Bolt when nearly empty and cut it off at when it starts throttling down or starts becoming slower than that 30 kWh Leaf. In https://electricrevs.com/2018/07/17/wat ... -to-55-kw/, during his testing, it dropped below 54 kW charging rate once he passed 54% SoC. Was full power up until that point.

Also, if you started with a full charge on each, the Bolt would go about 2x as far as the 30 kWh Leaf on the initial charge. And, if you did multiple DC FCs in a day, I bet that 30 kWh battery would overheat and throttling might begin sooner whereas Bolt has battery thermal management.

edit: In Jeff's test, from about 54% to about 70%, he was maintaining 38+ kW charging rate. Then it sharply dropped off to about 23 to 24-ish kW.
In your test it could happen. I have yet to have time to look for the link but pretty sure test required charging to 80% which obviously favored the 30 kwh. As far as multiple QCs eventually slowing the charge rate? I hit 131º (11 bars I think) on mine with no slow down in sight. This was a work day so time was of the essence and other than speeding (half the trip was roads with 55 mph speed limits but a lot of up and down so I admit to hitting 75 mph coasting in neutral...) it was a 14 hour day with only two "work" stops each less than 30 mins. So it was mostly driving and charging

Under more extreme conditions like crossing the Mojave? Yeah that might do it or even mundane conditions of a 100º day which you see frequently and I read about occasionally, it could happen.

TBT; this test like any other; it had an agenda to prove and they proved it. I saw a Bolt charging at 131 amps at EVGO Tacoma and luckily I took a pix right away because, I turned to start my charge and returned just 2-3 mins later and the rate had dropped to 85 amps. I get the ramp down but that was extreme and the weather was not hot
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

Sat May 18, 2019 2:02 am

Guys, although I'm new to this forum I am not new to forums in general.
Don't you think you've gone off topic?
Also, quoting the quote of the quote does nothing to the conversation. It just takes space and confuses anyone reading.
When quoting, please select the part that you refer to not the entire post.

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

Sat May 18, 2019 2:22 am

SageBrush wrote:The functional limitations of the LEAF are hard to convey to people not versed in the EV world.
.....
Between having a large battery, fast L2 and Tesla network access, and actually fast DC charging as a back-up plan the EV does not restrict where we travel. Any LEAF, including the 62 kWh version, would have been a non-starter even with an overnight stay somewhere.
I agree that the Leaf has some (sadly non-disclosed) functional limitations but your example refers to charger availability.

I don't have an avilailability issue but an overheating one. There are enough chargers around to plan decent trips.

The problem I have with the Leaf is that it builds up heat during QC and never dissipates it once the charge has ended and the car is moving again.

So one arrives at next charging station with a warm/hot battery which causes the computer to throttle down the charge power. This limits the charges to max 3 or even 2 a day before you must stop and let the car cool down mainly overnight.

Nissan does not disclose this limitation.

SageBrush
Posts: 4748
Joined: Sun Mar 06, 2011 2:28 am
Delivery Date: 13 Feb 2017
Location: NM

Re: 2019 Leaf battery overheating

Sat May 18, 2019 6:51 am

metricus wrote:
SageBrush wrote:The functional limitations of the LEAF are hard to convey to people not versed in the EV world.
.....
Between having a large battery, fast L2 and Tesla network access, and actually fast DC charging as a back-up plan the EV does not restrict where we travel. Any LEAF, including the 62 kWh version, would have been a non-starter even with an overnight stay somewhere.
I agree that the Leaf has some (sadly non-disclosed) functional limitations but your example refers to charger availability.
This is why I wrote actually fast charger.
My 'plan B' was an extra hour or two of trip time but it was OK because I would reach a 150 kW charger.
In any case, I was trying to convey that a successful trip is a dance that depends on battery size, charging network locations and functionality, and car charging functionality. Sometimes one impairment can be worked around if the others are robust. This kind of one-off planning does not fit into a sales brochure. It is just too much a ymmv.

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 ?

It has recently become more clear in the Tesla world that Supercharging speeds are low when the battery is cold. Call it cold-gate :)
That information was never conveyed by Tesla to potential customers. This issue does not matter to most people for a variety of reasons but I'm sure there is at least one person somewhere who finds it a big problem in their car use.
2013 LEAF 'S' Model with QC & rear-view camera
Bought off-lease Jan 2017 from N. California
Two years in Colorado, now in NM
03/2018: 58 Ahr, 28k miles
11/2018: 56.16 Ahr, 30k miles
-----
2018 Tesla Model 3 LR, Delivered 6/2018

DaveinOlyWA
Posts: 14107
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

Sat May 18, 2019 8:18 am

DaveinOlyWA wrote:
cwerdna wrote:
DaveinOlyWA wrote:
In a race with the Bolt, 30 kwh LEAF and 40 kwh LEAF, who would win?

Winner; 30 kwh LEAF simply because of its ability to charge at full speed to 80% SOC. Test based on 5 mins plus charge time for each QC stop. There were parameters for trip length with Bolt and 40 having advantage in shorter distances due to higher range which was GREATLY mitigated if all cars started race at 50% SOC.

FYI; The 30 wins barely if the race is long enough BUT the 40 loses badly in anything over 300 miles or so.

But the main advantage of having a bigger pack is simply more charging options convenient to personal needs (which often do not follow a schedule) and the ability to charge the lower 2/3rds of the pack (something Bolt excels) which helps to slow temperature rise.
You think so?

With a sufficiently powerful DC FC. I think the Bolt would win if you only started charging the Bolt when nearly empty and cut it off at when it starts throttling down or starts becoming slower than that 30 kWh Leaf. In https://electricrevs.com/2018/07/17/wat ... -to-55-kw/, during his testing, it dropped below 54 kW charging rate once he passed 54% SoC. Was full power up until that point.

Also, if you started with a full charge on each, the Bolt would go about 2x as far as the 30 kWh Leaf on the initial charge. And, if you did multiple DC FCs in a day, I bet that 30 kWh battery would overheat and throttling might begin sooner whereas Bolt has battery thermal management.

edit: In Jeff's test, from about 54% to about 70%, he was maintaining 38+ kW charging rate. Then it sharply dropped off to about 23 to 24-ish kW.
In your test it could happen. I have yet to have time to look for the link but pretty sure test required charging to 80% which obviously favored the 30 kwh. As far as multiple QCs eventually slowing the charge rate? I hit 131º (11 bars I think) on mine with no slow down in sight. This was a work day so time was of the essence and other than speeding (half the trip was roads with 55 mph speed limits but a lot of up and down so I admit to hitting 75 mph coasting in neutral...) it was a 14 hour day with only two "work" stops each less than 30 mins. So it was mostly driving and charging

Under more extreme conditions like crossing the Mojave? Yeah that might do it or even mundane conditions of a 100º day which you see frequently and I read about occasionally, it could happen.

TBT; this test like any other; it had an agenda to prove and they proved it. I saw a Bolt charging at 131 amps at EVGO Tacoma and luckily I took a pix right away because, I turned to start my charge and returned just 2-3 mins later and the rate had dropped to 85 amps. I get the ramp down but that was extreme and the weather was not hot
Guess what!

I ran into someone I know who had just gotten a Bolt a few weeks earlier. He was charging faster than the earlier Bolt using the same station. He was at 58% and still pulling 98 amps. My thought was Bolt charging profile was updated but that doesn't seem to be the case (or commonly known) so have to think heat is was the culprit on earlier Bolt?

Makes me wonder how effective Bolt TMS is? How much power does it use?
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;

SageBrush
Posts: 4748
Joined: Sun Mar 06, 2011 2:28 am
Delivery Date: 13 Feb 2017
Location: NM

Re: 2019 Leaf battery overheating

Sat May 18, 2019 8:49 am

DaveinOlyWA wrote: Guess what!

I ran into someone I know who had just gotten a Bolt a few weeks earlier. He was charging faster than the earlier Bolt using the same station. He was at 58% and still pulling 98 amps. My thought was Bolt charging profile was updated but that doesn't seem to be the case (or commonly known) so have to think heat is was the culprit on earlier Bolt?
Batteries vary by 5% easy, and you have not even considered the charger yet.
2013 LEAF 'S' Model with QC & rear-view camera
Bought off-lease Jan 2017 from N. California
Two years in Colorado, now in NM
03/2018: 58 Ahr, 28k miles
11/2018: 56.16 Ahr, 30k miles
-----
2018 Tesla Model 3 LR, Delivered 6/2018

DaveinOlyWA
Posts: 14107
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

Sat May 18, 2019 9:12 am

SageBrush wrote:
DaveinOlyWA wrote: Guess what!

I ran into someone I know who had just gotten a Bolt a few weeks earlier. He was charging faster than the earlier Bolt using the same station. He was at 58% and still pulling 98 amps. My thought was Bolt charging profile was updated but that doesn't seem to be the case (or commonly known) so have to think heat is was the culprit on earlier Bolt?
Batteries vary by 5% easy, and you have not even considered the charger yet.
Exact same charger which still charges at same rate as before. Since I have a 30 min time limit, I check these regularly as max current varies from station to station on my LEAF so always pick the one that runs at 124 amps over the other two at 118 and 121 if it is available.

The interesting thing is the Bolt charges at "up to" 131 amps on the charger that only gives me 121 amps. So why don't I get 124?
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;

SageBrush
Posts: 4748
Joined: Sun Mar 06, 2011 2:28 am
Delivery Date: 13 Feb 2017
Location: NM

Re: 2019 Leaf battery overheating

Sat May 18, 2019 9:46 am

DaveinOlyWA wrote:
SageBrush wrote:
DaveinOlyWA wrote: Guess what!

I ran into someone I know who had just gotten a Bolt a few weeks earlier. He was charging faster than the earlier Bolt using the same station. He was at 58% and still pulling 98 amps. My thought was Bolt charging profile was updated but that doesn't seem to be the case (or commonly known) so have to think heat is was the culprit on earlier Bolt?
Batteries vary by 5% easy, and you have not even considered the charger yet.
Exact same charger which still charges at same rate as before.
Another couple variables you forget :

Other activity, other cars
Time the car is charging
Ambient temperature

... the list is long
2013 LEAF 'S' Model with QC & rear-view camera
Bought off-lease Jan 2017 from N. California
Two years in Colorado, now in NM
03/2018: 58 Ahr, 28k miles
11/2018: 56.16 Ahr, 30k miles
-----
2018 Tesla Model 3 LR, Delivered 6/2018

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