TexasLeaf
Posts: 103
Joined: Wed Mar 21, 2018 5:37 am
Delivery Date: 17 Mar 2018
Leaf Number: 303111
Location: Texas

Re: Rapidgate fixed

Wed Jan 23, 2019 3:25 pm

There is an article on electrive.com that states that #Rapidgate fix software update for 2018 Leafs manufactured before May 2018 is now available. I have talked to my local Nissan dealership but so far they don’t know anything about the update. Has anyone had any success getting the update on thier 2018 Leaf?
2018 Leaf SL
2015 Ford Fusion Energi Titanium
2007 GMC Envoy XL SLT 4X4

DaveinOlyWA
Posts: 13838
Joined: Sat Apr 24, 2010 7:43 pm
Delivery Date: 16 Feb 2018
Leaf Number: 314199
Location: Olympia, WA
Contact: Website

Re: Rapidgate fixed

Wed Jan 23, 2019 7:12 pm

i am giving it a month.
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: 4045
Joined: Sun Mar 06, 2011 2:28 am
Delivery Date: 13 Feb 2017
Location: Colorado

Re: Rapidgate fixed

Wed Jan 23, 2019 9:51 pm

arnis wrote:70kW is likely equilibrium point where charging and driving at medium speed in medium weather will
cool down the pack enough for next 180A peak charge rate (70kW).

I'll be surprised if this turns out to be true.
I expect the first charge to be as you described and subsequent charge rates to be in the toilet unless it is freezing outside, just like the 40 kWh LEAF.
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

kovadam
Posts: 30
Joined: Wed Jun 06, 2018 12:07 am
Delivery Date: 28 Sep 2018
Location: Hungary, Europe

Re: Rapidgate fixed

Thu Jan 24, 2019 1:09 am

Well if you drive the 62kWh Leaf normally, where peak energy draw from the battery pack remains below 20kW, the pack can cool itself slowly while driving, since taking 20kW or less from the pack means 0.3C or below, where the cells are not heating up any more. This is why 40kWh battery gets slightly warmer and warmer while you drive. For the 40kWh battery pack this is somewere around 12-13kW, which means 0.3C. This is why the rapidgate charge rate tapering was around this point, as below this energy draw the pack can cool itself down, the cells are not heated any more due to charging or discharging. Since the 62kWh pack is 30% more, you can also draw/or put 30% more energy without heating up the pack.

So if you QC with 70kW (which is only 1.12C compared to the 50kW in the 40kWh battery pack which is 1.25) the heat which builds up during charging is lower, and if you drive after without draining more than 20kW, the pack will cool down till you arrive to the next charge point.

So based on this, I assume, rapidgate will almost never be an issue for the 62kWh Leaf until you do not exceed 100/110kmh speed.

SageBrush
Posts: 4045
Joined: Sun Mar 06, 2011 2:28 am
Delivery Date: 13 Feb 2017
Location: Colorado

Re: Rapidgate fixed

Thu Jan 24, 2019 8:26 am

^^ The 62 kWh pack is proportionally more dense than the 40 kWh pack; its heat removal per time will be impaired compared to the 40 kWh pack. Moreover, the 40 kWh pack takes the better part of 18 hours once parked to drop below 80F *outside* of the summer.

I'll be happy to make a friendly wager that the 62 kWh pack continues to heat up as you drive unless it is cold outside; that the first charge brings it up to a toasty temperature of ~ 120F, and that the pack stays there on subsequent charges with the charging rate then limited by the heat removal accomplished by the AC cooling
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

DaveinOlyWA
Posts: 13838
Joined: Sat Apr 24, 2010 7:43 pm
Delivery Date: 16 Feb 2018
Leaf Number: 314199
Location: Olympia, WA
Contact: Website

Re: Rapidgate fixed

Thu Jan 24, 2019 9:29 am

This is a non point that I will throw out there anyway. The variables are obvious so you can consider this BS (as I am sure you are more than willing to do) but it would seem the delta would be roughly 20-25º to see cooling of the pack while driving.

The above only works for me. You can now make your own claims.
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;

arnis
Posts: 951
Joined: Sat Jan 23, 2016 3:21 pm
Delivery Date: 23 Jul 2014
Leaf Number: 015896
Location: Estonia, Europe

Re: Rapidgate fixed

Thu Jan 24, 2019 9:48 am

kovadam is on the right track. Such low C- rates for charge (1,2) and discharge (0,3) will have tiny inefficiency.
And 2-hour drive between charging sessions will allow much more cooling just due to time.
Short range EVs <30kWh -- Medium range: 30-60kWh -- Long range: >60kWh
Charging: Trickle <3kW -- Normal 3-22kW -- Fast 50-100kW -- Supercharging >100kW

lorenfb
Posts: 2191
Joined: Tue Dec 17, 2013 10:53 pm
Delivery Date: 22 Nov 2013
Leaf Number: 416635
Location: SoCal

Re: Rapidgate fixed

Thu Jan 24, 2019 10:16 am

SageBrush wrote:^^ The 62 kWh pack is proportionally more dense than the 40 kWh pack; its heat removal per time will be impaired compared to the 40 kWh pack. Moreover, the 40 kWh pack takes the better part of 18 hours once parked to drop below 80F *outside* of the summer.

I'll be happy to make a friendly wager that the 62 kWh pack continues to heat up as you drive unless it is cold outside; that the first charge brings it up to a toasty temperature of ~ 120F, and that the pack stays there on subsequent charges with the charging rate then limited by the heat removal accomplished by the AC cooling


Yes, it's all about simple thermodynamics and the battery's thermal resistance to ambient, given no significant battery thermal management.
Since all batteries have an internal resistance, battery heat will always be developed whether driving or charging. So it's a simple function
of how much heat is developed, e.g. via vehicle speed and/or charging level, the temperature delta between the battery cells and ambient,
and the overall thermal resistance of the cells to ambient. Thus, the temperature delta is the key controllable variable!
#1 Leaf SL MY 9/13: 74K miles, 48 Ahrs, 5.2 miles/kWh (average), Hx=70, SOH=78, L2 - 100% > 1000, temp < 95F (35C), min discharge (DOD) > 20 Ahrs
#2 Leaf SL MY 12/18: 115 Ahrs, 5.5 miles/kWh (average), Hx=98, SOH=99, DOD > 25%, temp < 105F

kovadam
Posts: 30
Joined: Wed Jun 06, 2018 12:07 am
Delivery Date: 28 Sep 2018
Location: Hungary, Europe

Re: Rapidgate fixed

Fri Jan 25, 2019 2:33 am

lorenfb wrote:
SageBrush wrote:^^ The 62 kWh pack is proportionally more dense than the 40 kWh pack; its heat removal per time will be impaired compared to the 40 kWh pack. Moreover, the 40 kWh pack takes the better part of 18 hours once parked to drop below 80F *outside* of the summer.

I'll be happy to make a friendly wager that the 62 kWh pack continues to heat up as you drive unless it is cold outside; that the first charge brings it up to a toasty temperature of ~ 120F, and that the pack stays there on subsequent charges with the charging rate then limited by the heat removal accomplished by the AC cooling


Yes, it's all about simple thermodynamics and the battery's thermal resistance to ambient, given no significant battery thermal management.
Since all batteries have an internal resistance, battery heat will always be developed whether driving or charging. So it's a simple function
of how much heat is developed, e.g. via vehicle speed and/or charging level, the temperature delta between the battery cells and ambient,
and the overall thermal resistance of the cells to ambient. Thus, the temperature delta is the key controllable variable!


Temperature delta is only a key in how fast the pack cools. If the delta is huge, cools faster, if small, cools lower, however how much the battery pack heats up, is depending on the resistance of the cells (as you wrote), but it is also depending how many current you push through the cells. If the current is low, the heat is low, if the current is high, the heat generated is high. And this is where the C rates come in question, if the C rates are low, current drown from each cell are low, therefore the heat generated is low.

There are 288 cells instead of 196 (or so), so double amount, and the charging power is 70kW (400V 175A) this 175A current is divided into 288 cells so each cell will get 0,6A or 600mA current. In the 40kWh leaf the charge rate is 50kW (400V 125A) this 125A current is divided into 196 cells, which means 0.63A or 630mA current, which is similar for charging. But for discharging (as you drive), if we say 20kWh/100km is a quite faster driving pattern than normal the 40kWh cells are drained with 0.25A or 250mA and the 62kWh batter cells are drained only with 0.17A or 170mA which will result in a much lower heat build up (current was calculated with constant 400V, of course current will increase as battery pack voltage drops, this is only for demo calculations).

Actually the 40kWh battery pack is not heating up, if you drain constantly less power than 12kW. With 62kWh pack this is around 20kW probably, so this means if you drive normally, and drain less power from the battery pack, it can cool down instead of heating up, like the 40kWh pack. If you achieve an average consumption of 15kWh/100km, then you already heated up the 40kWh pack a little bit, however the 62kWh pack could cooled down a little bit with this. Check out on youtube Jame's (Lemon Tea Leaf) video about how he achieved to keep the temp down. He managed to cool down the pack by several °C through not taking more power from the pack as 12-15kW.

How fast it's cooling down, depends on the temperature difference (delta). But the heat build up depends on the current that flows through the cells.

lorenfb
Posts: 2191
Joined: Tue Dec 17, 2013 10:53 pm
Delivery Date: 22 Nov 2013
Leaf Number: 416635
Location: SoCal

Re: Rapidgate fixed

Fri Jan 25, 2019 5:13 pm

kovadam wrote:
lorenfb wrote:
SageBrush wrote:^^ The 62 kWh pack is proportionally more dense than the 40 kWh pack; its heat removal per time will be impaired compared to the 40 kWh pack. Moreover, the 40 kWh pack takes the better part of 18 hours once parked to drop below 80F *outside* of the summer.

I'll be happy to make a friendly wager that the 62 kWh pack continues to heat up as you drive unless it is cold outside; that the first charge brings it up to a toasty temperature of ~ 120F, and that the pack stays there on subsequent charges with the charging rate then limited by the heat removal accomplished by the AC cooling


Yes, it's all about simple thermodynamics and the battery's thermal resistance to ambient, given no significant battery thermal management.
Since all batteries have an internal resistance, battery heat will always be developed whether driving or charging. So it's a simple function
of how much heat is developed, e.g. via vehicle speed and/or charging level, the temperature delta between the battery cells and ambient,
and the overall thermal resistance of the cells to ambient. Thus, the temperature delta is the key controllable variable!


Temperature delta is only a key in how fast the pack cools. If the delta is huge, cools faster, if small, cools lower, however how much the battery pack heats up, is depending on the resistance of the cells (as you wrote), but it is also depending how many current you push through the cells. If the current is low, the heat is low, if the current is high, the heat generated is high. And this is where the C rates come in question, if the C rates are low, current drown from each cell are low, therefore the heat generated is low.

There are 288 cells instead of 196 (or so), so double amount, and the charging power is 70kW (400V 175A) this 175A current is divided into 288 cells so each cell will get 0,6A or 600mA current. In the 40kWh leaf the charge rate is 50kW (400V 125A) this 125A current is divided into 196 cells, which means 0.63A or 630mA current, which is similar for charging. But for discharging (as you drive), if we say 20kWh/100km is a quite faster driving pattern than normal the 40kWh cells are drained with 0.25A or 250mA and the 62kWh batter cells are drained only with 0.17A or 170mA which will result in a much lower heat build up (current was calculated with constant 400V, of course current will increase as battery pack voltage drops, this is only for demo calculations).

Actually the 40kWh battery pack is not heating up, if you drain constantly less power than 12kW. With 62kWh pack this is around 20kW probably, so this means if you drive normally, and drain less power from the battery pack, it can cool down instead of heating up, like the 40kWh pack. If you achieve an average consumption of 15kWh/100km, then you already heated up the 40kWh pack a little bit, however the 62kWh pack could cooled down a little bit with this. Check out on youtube Jame's (Lemon Tea Leaf) video about how he achieved to keep the temp down. He managed to cool down the pack by several °C through not taking more power from the pack as 12-15kW.

How fast it's cooling down, depends on the temperature difference (delta). But the heat build up depends on the current that flows through the cells.


Nothing really new added, basically just paraphrasing the same as was previously posted! DaveinOlyWA performed a basic test on his
40kWh Leaf that indicated the battery's internal resistance to be about 100 milliohms. So when charging at about 40kW the battery
will be dissipating about 1,000 watts (100^2 amps X .100 ohms). Typically when driving at about 60 MPH (level terrain), the battery
current is about 30 - 40 amps, which results in about 90 to 160 watts of battery power dissipation - heat. Given a high thermal battery
resistance to ambient for the Leaf, the temperature gradient to ambient needs to be significant, when multiple sequential QCs
occur to prevent excess battery heat, or limiting successive high current charging.
Last edited by lorenfb on Fri Jan 25, 2019 8:20 pm, edited 1 time in total.
#1 Leaf SL MY 9/13: 74K miles, 48 Ahrs, 5.2 miles/kWh (average), Hx=70, SOH=78, L2 - 100% > 1000, temp < 95F (35C), min discharge (DOD) > 20 Ahrs
#2 Leaf SL MY 12/18: 115 Ahrs, 5.5 miles/kWh (average), Hx=98, SOH=99, DOD > 25%, temp < 105F

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