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Re: Rapidgate on the 62 kWh Leaf Plus?

Posted: Tue May 07, 2019 6:54 am
by SageBrush
WetEV wrote:
SageBrush wrote:
WetEV wrote:
I'd bet
Don't worry, the LEAF will just reach the rapid-gate threshold in 1/4 the time
Except it doesn't.
Because it doesn't charge at 100 kW.

The current kludge to decide on charging rate based on battery temperature at the start of charging is reliant on slow charging, otherwise the battery would heat up to cooking temps.

Re: Rapidgate on the 62 kWh Leaf Plus?

Posted: Tue May 07, 2019 7:03 am
by WetEV
SageBrush wrote:
WetEV wrote:
SageBrush wrote: Don't worry, the LEAF will just reach the rapid-gate threshold in 1/4 the time
Except it doesn't.
Because it doesn't charge at 100 kW
The LEAF also doesn't do 139MPH. So?

Most charging is at home. At 1kW to 6kW.

LEAF doesn't have a fire problem. Tesla does.

https://www.businessinsider.com/why-tes ... ire-2019-4

I don't want a battery pack with water in it.

Re: Rapidgate on the 62 kWh Leaf Plus?

Posted: Tue May 07, 2019 7:38 am
by SageBrush
WetEV wrote:
SageBrush wrote:
WetEV wrote:
Except it doesn't.
Because it doesn't charge at 100 kW
The LEAF also doesn't
Yeah ... the list is long, including charging at 100 kW which is what the fellow I responded to was asking about. Now now, not in the future for his model. The cooling design just does not have anywhere near the heat dissipation capacity required.

Re: Rapidgate on the 62 kWh Leaf Plus?

Posted: Tue May 07, 2019 8:07 am
by WetEV
SageBrush wrote:
WetEV wrote:
SageBrush wrote: Because it doesn't charge at 100 kW
The LEAF also doesn't
Yeah ... the list is long, including charging at 100 kW which is what the fellow I responded to was asking about. Now now, not in the future for his model. The cooling design just does not have anywhere near the heat dissipation capacity required.
And doesn't have water in the battery case.

https://abc7news.com/automotive/tesla-m ... e/5283936/

Re: Rapidgate on the 62 kWh Leaf Plus?

Posted: Tue May 07, 2019 8:31 am
by lorenfb
stutech wrote:From what I can tell though my battery cools back down before I get to the next charger on the plus model with 50kw charging. My average speeds have been 65-70mph and the ambient temp was 60-80F. I would love to see how it does at 100kw charging with even warmer temps to get a true assessment.
It might be advisable to use LeadSpy to monitor your battery temperature after a QC or when driving at speeds greater than 55 mph.
The thermal time constant of the Leaf's battery to ambient is fairly lengthy, greater than an hour for a temp delta of 20 degrees,
i.e. the Leaf battery's thermal resistance to ambient is high. When charging or driving at the speed noted, the battery heats up
quickly, 10 - 15 minutes for a temp delta increase of 20 degrees, i.e. the Leaf's battery heats quickly the result of the battery's I^2 X R
losses from high QC rates or heavy motor loads. The high thermal resistance to ambient also results in a lengthy cool down time for
the Leaf battery.

Re: Rapidgate on the 62 kWh Leaf Plus?

Posted: Tue May 07, 2019 8:34 am
by SageBrush
lorenfb wrote: The thermal time constant of the Leaf's battery to ambient is fairly lengthy, greater than an hour for a temp delta of 20 degrees,
Did you mean a day ?

Re: Rapidgate on the 62 kWh Leaf Plus?

Posted: Tue May 07, 2019 8:54 am
by OrientExpress
I am in the process of putting up a story on a 500 mile trip I took in a LEAF Plus from San Jost to Tahoe and back, and will post the link when it is done. I also charged it using the EVGo 85kW (100 peak) chargers.

The bottom line is that the battery does not seem to have any heat sensitivity or build up. Once the battery warms up to the mid-point on the temperature gauge, it stays there, even after running the car hard, then quick charging. On average with the faster chargers on shared sources the car would charge at about 58 kW and on the 50 kW chargers would charge at about 45 kW.

Image

This photo is after a 85kW (57kW) charge session, and previous to that lots of very fast freeway driving.

Re: Rapidgate on the 62 kWh Leaf Plus?

Posted: Tue May 07, 2019 8:58 am
by WetEV
OrientExpress wrote:This photo is after a 85kW (57kW) charge session, and previous to that lots of very fast freeway driving.
What was the actual battery temperature? I can't decode idiot lights and bars without a cheat sheet.

Re: Rapidgate on the 62 kWh Leaf Plus?

Posted: Tue May 07, 2019 9:01 am
by OrientExpress
WetEV wrote:What was the actual battery temperature?.
It was in the middle of the acceptable heat range for the 62 kWh battery.

Re: Rapidgate on the 62 kWh Leaf Plus?

Posted: Tue May 07, 2019 9:01 am
by lorenfb
SageBrush wrote:
lorenfb wrote: The thermal time constant of the Leaf's battery to ambient is fairly lengthy, greater than an hour for a temp delta of 20 degrees,
Did you mean a day ?
After a 30 minute QC (avg power 30 kW) on my 2019 40 kWh Leaf, the battery temp reached 100F, ambient of 75F. After driving for
about 45 minutes at 35 - 40, the battery temp was at 80F. So based on that QC and driving at speeds greater than 50 -55 while
monitoring the Leaf's battery temp, my view is to only have one QC per day (or at best none), and limit my speed. My experience
is that any speeds greater than 50-55 for lengthy periods results in undesirable battery temps.