Multiple DC Quick Charges did get a Hot Battery for this guy

[edatoakrun]

That 10.5 hours time for a 250 mile (IIRC) drive was due to delay by the driver, and/or due to less-than-fully-available QC locations.

A 250 mile drive on a high-speed freeway like I-5 puts about a 3 hour "penalty" on a QC BEV driver, as opposed to an ICEV.

I wouldn't want to take that much extra time, and I don't think many others would, either.

On lower-speed roads, or shorter trips, the BEV time penalty would be much less.

The ICEV cost penalty will also vary, with the future prices of gasoline and electricity, of course.

Somehow the math in that does not seem to make sense.

250 miles with QC should not take that long...realistically, one could expect to go ~ 50 miles on a 80% charge at freeway speeds?
That means you need 4 QC s for the trip i.e. at 50, 100, 150 and 200 miles. Each takes 20 minutes, so 80 minutes penalty vs. ICE which can do the whole trip in one leg. if you add some extra minutes for getting to and from the charger, maybe a bit longer.

A 3 h penalty would imply that each QC would take 45 minutes which would be twice as long as advertised...

If there wasn't about 6,200 ft of total ascent (1700 ft net) driving South, you used no climate control, both vehicles drove less than the 75 MPH (?) customary ICEV speed, the charge stations are all right at the exits, and located at exactly the right intervals, in every case, etc., I still doubt an ICEV driving non-stop, Couldn't beat your BEV time, by well over 2 hours.

Sorry, I might have said about 2 1/2 hours headed North, and about 3 hours, headed South, for this stretch of I-5, but I was just trying to make a single, realistic, estimate.

 

[Ingineer]

An alternate explanation, is that, since there are multiple temperature readings available from the battery pack, the temperature levels you are getting from different sources, are compiled from different readings, or even as modified by a further "time at temp" calculation, used by Nissan to more accurately model high temp effects on the entire battery pack.

Certainly plausible. There are four temp probes, and I'm sure each thermister reads a slightly different resistance reading when it goes into the magic box to be sorted out as the battery temperature. I would not be surprised that the battery temp gauge has been changed from the official service manual index.

The decisions are made on whatever temp sensor is reading the hottest. The Battery ECU sends out the hottest temp reading of the 4.

-Phil

 

[edatoakrun]

An alternate explanation, is that, since there are multiple temperature readings available from the battery pack, the temperature levels you are getting from different sources, are compiled from different readings, or even as modified by a further "time at temp" calculation, used by Nissan to more accurately model high temp effects on the entire battery pack.

Certainly plausible. There are four temp probes, and I'm sure each thermister reads a slightly different resistance reading when it goes into the magic box to be sorted out as the battery temperature. I would not be surprised that the battery temp gauge has been changed from the official service manual index.

The decisions are made on whatever temp sensor is reading the hottest. The Battery ECU sends out the hottest temp reading of the 4.

-Phil

So, do you know at what temp display bar, and temperature, the LEAF will restrict (stop?) charging, or kW use (turtle?) while driving?

 

[planet4ever]

250 miles with QC should not take that long...realistically, one could expect to go ~ 50 miles on a 80% charge at freeway speeds? That means you need 4 QC s for the trip i.e. at 50, 100, 150 and 200 miles. Each takes 20 minutes, so 80 minutes penalty vs. ICE which can do the whole trip in one leg.

I don't believe you can get anywhere close to an 80% charge in 20 minutes. Given the maximum charging rate of 48kW you could theoretically get 16kWh in 20 minutes, and that is 80% of a (rather low) 20 kWh assumption for battery capacity, but I don't think anyone has reported holding that maximum charge rate for the entire time. Nissan says you can get a 63% charge (LBW to 80%) in approximately half an hour.

Ray

 

[GRA]

250 miles with QC should not take that long...realistically, one could expect to go ~ 50 miles on a 80% charge at freeway speeds? That means you need 4 QC s for the trip i.e. at 50, 100, 150 and 200 miles. Each takes 20 minutes, so 80 minutes penalty vs. ICE which can do the whole trip in one leg.

I don't believe you can get anywhere close to an 80% charge in 20 minutes. Given the maximum charging rate of 48kW you could theoretically get 16kWh in 20 minutes, and that is 80% of a (rather low) 20 kWh assumption for battery capacity, but I don't think anyone has reported holding that maximum charge rate for the entire time. Nissan says you can get a 63% charge (LBW to 80%) in approximately half an hour.

Ray

Agreed. Personally, the most I would be willing to do routinely would be one en-route QC (each way) for a day trip, two for a weekend trip, or _maybe_ three if it's somewhere I _really_ want to go. Ideally, I'd want to eliminate at least 1 en-route QC each way for each of them. But the Leaf's range is just too short for me to make many of my weekend trips to the mountains efficient and practical, given thousands of feet of climb, night driving and colder temps.

For example, going to Yosemite in a Leaf via S.R. 120 from my home in the Bay Area (0 mi.), I'd probably have to charge in Manteca (55 miles from home), Oakdale (75 mi. F.H., short charge) and Groveland (112 mi. F.H., 3,100 ft.), and might well need another charge at Crane Flat (150 mi. F.H., 6,200 ft.); certainly so if I were going to Tuolumne Meadows (8,600 ft.). The total distance is something like 170 and 190 miles respectively, and I could normally drive them in 3 and 3.5 hours (typically Friday evening). Trying to get to Lake Tahoe by Leaf would be similarly wasteful of time (it would be semi-reasonable for those in the Sacramento area).

In the 31kWh Coda I could probably make it to Oakdale non-stop (maybe with some care), Groveland and then non-stop to Yosemite Valley; going to Tuolumne will always require a stop at Crane Flat. To get to Groveland non-stop I'd probably require a (flat ground) freeway range of at least 150 miles, and 175 or more might be necessary.

So, long trips by current BEVs (other than Teslas) using QCs don't make any sense. Putting QCs along I-5 in Oregon is reasonable, making trips between adjacent or next adjacent metropolitan areas in the Willamette Valley reasonable. And putting them along the corridor between San Diego and L.A. is also reasonable, and (for Edatoakrun) we can put them along I-5 up the Sacramento Valley. But in the San Joaquin Valley, given current BEV range (Tesla can take care of themselves) no one in their right mind will use a BEV for long north-south trips on I-5. Right now, the QCs in the San Joaquin Valley shouldn't be on I-5 except at junctions with major East-West routes (i.e. Santa Nella). They should be installed to facilitate trips between the Sacramento and S.F. metropolitan areas and the Sierra, i.e. along I-80, U.S. 50, S.R. 120/140 etc. If we want an electric highway in the San Joaquin Valley now it should be S.R. 99, not I-5, because that's where the cities/people are.

 

[GaslessInSeattle]

Two important points missed here. First off, the most significant effect of a QC network is psychological. just simply knowing that you can theoretically drive continuously will be a re-leaf to quite a few folks and don't think there won't be a contest to see who is the first to make it from Canada to the Mexico border once it's possible. QC's from border to border on I-5 will be a big PR boon for EV's even if some of them are hardly ever used. The second major thing that is missed with the idea of an extensive network is the reality that in a few short years battery capacity will be rising. the next big jump may very well be double today's capacity, making longer trips possible and QC stops possible. I don't think the QC network should be built with just today's limits in mind but assuming that more and more over time, people will venture further and with bigger batteries. Surely, as the EV population grows, we will want QC stations even closer together, more like gas stations today, to spread out the demand.

250 miles with QC should not take that long...realistically, one could expect to go ~ 50 miles on a 80% charge at freeway speeds? That means you need 4 QC s for the trip i.e. at 50, 100, 150 and 200 miles. Each takes 20 minutes, so 80 minutes penalty vs. ICE which can do the whole trip in one leg.

I don't believe you can get anywhere close to an 80% charge in 20 minutes. Given the maximum charging rate of 48kW you could theoretically get 16kWh in 20 minutes, and that is 80% of a (rather low) 20 kWh assumption for battery capacity, but I don't think anyone has reported holding that maximum charge rate for the entire time. Nissan says you can get a 63% charge (LBW to 80%) in approximately half an hour.

Ray

Agreed. Personally, the most I would be willing to do routinely would be one en-route QC (each way) for a day trip, two for a weekend trip, or _maybe_ three if it's somewhere I _really_ want to go. Ideally, I'd want to eliminate at least 1 en-route QC each way for each of them. But the Leaf's range is just too short for me to make many of my weekend trips to the mountains efficient and practical, given thousands of feet of climb, night driving and colder temps.

For example, going to Yosemite in a Leaf via S.R. 120 from my home in the Bay Area (0 mi.), I'd probably have to charge in Manteca (55 miles from home), Oakdale (75 mi. F.H., short charge) and Groveland (112 mi. F.H., 3,100 ft.), and might well need another charge at Crane Flat (150 mi. F.H., 6,200 ft.); certainly so if I were going to Tuolumne Meadows (8,600 ft.). The total distance is something like 170 and 190 miles respectively, and I could normally drive them in 3 and 3.5 hours (typically Friday evening). Trying to get to Lake Tahoe by Leaf would be similarly wasteful of time (it would be semi-reasonable for those in the Sacramento area).

In the 31kWh Coda I could probably make it to Oakdale non-stop (maybe with some care), Groveland and then non-stop to Yosemite Valley; going to Tuolumne will always require a stop at Crane Flat. To get to Groveland non-stop I'd probably require a (flat ground) freeway range of at least 150 miles, and 175 or more might be necessary.

So, long trips by current BEVs (other than Teslas) using QCs don't make any sense. Putting QCs along I-5 in Oregon is reasonable, making trips between adjacent or next adjacent metropolitan areas in the Willamette Valley reasonable. And putting them along the corridor between San Diego and L.A. is also reasonable, and (for Edatokrun) we can put them along I-5 up the Sacramento Valley. But in the San Joaquin Valley, given current BEV range (Tesla can take care of themselves) no one in their right mind will use a BEV for long north-south trips on I-5. Right now, the QCs in the San Joaquin Valley shouldn't be on I-5 except at junctions with major East-West routes (i.e. Santa Nella). They should be installed to facilitate trips between the Sacramento and S.F. metropolitan areas and the Sierra, i.e. along I-80, U.S. 50, S.R. 120/140 etc. If we want an electric highway in the San Joaquin Valley now it should be S.R. 99, not I-5, because that's where the cities/people are.

 

[klapauzius]

250 miles with QC should not take that long...realistically, one could expect to go ~ 50 miles on a 80% charge at freeway speeds? That means you need 4 QC s for the trip i.e. at 50, 100, 150 and 200 miles. Each takes 20 minutes, so 80 minutes penalty vs. ICE which can do the whole trip in one leg.

I don't believe you can get anywhere close to an 80% charge in 20 minutes. Given the maximum charging rate of 48kW you could theoretically get 16kWh in 20 minutes, and that is 80% of a (rather low) 20 kWh assumption for battery capacity, but I don't think anyone has reported holding that maximum charge rate for the entire time. Nissan says you can get a 63% charge (LBW to 80%) in approximately half an hour.

Ray

I thought the maximum was 50 kW? Where do the 20 minutes to 80% come from...I am pretty sure I did not made them up. Is this the same as the "100 Mile" range, a very generous extrapolation of what could be possible under ideal circumstances?

This is from Nissans Webpage:

Q: What is the estimated time for full charging with 110v, 220v and quick-charge charge stations?
A: Starting from a depleted battery, about 20 hours at 110-120V (depending on amperage), approximately 7 hours at 208-240V (depending on amperage) and about 30 minutes at 480V (quick-charging station).

http://www.nissanusa.com/leaf-electric-car/faq/list/charging#/leaf-electric-car/faq/list/charging" onclick="window.open(this.href);return false;

So are they simply lying? Because the last 20% cannot be possibly charged in 10 minutes, can they?

If I take at face value what they say, then in "about 30 minutes" (which means at most 35 minutes for me) I can charge the car from "depleted" (i.e. zero bars or LBW or whatever) to "full" (meaning 12 bars).

Time to 80% ( if this was a linear process...I am aware it is not, but for simplicity sake lets assume that for a moment)

30 x 0.8 = 24 or "about" 20 minutes.

 

[mkjayakumar]

As I said the current Leaf owners getting excited by QC infrastructure is misplaced. The next generation maybe. With 30 mins charging times the range has to increase to 200+ miles, and of course if the battery capacity gets larger then the QC charging time also proportionately increases.

Assuming hypothetically the next generation leaf has 50kwh capacity and 170 miles highway range, then a 200 mile trip would have a 1.5 hr stoppage for charging, same as the current Leaf.

For higher adoption, we need three things in this order of importance:

1. Larger range approaching 200 miles
2. Quicker charging times than the current QCs
3. More QCs

 

[TimLee]

So the DC QC took his battery above 80%. Does anyone know if the charging timers work when using the DC QCs? I have mine set to start whenever I plug in but only charge to 80%. But that's at level 1 & 2. I've never quick charged.

If you are below 50%, the Blink QC will take you to close to 80%SOC and then the car shuts it off IF you set it to 90% on the QC. It makes no difference if you use the 'override' switch. Someone said that if you are at 50% or higher, it will take you to a little over 90% (100% setting on QC) if you use your override switch, but I've never QCd yet while at or over 50%. One of these days, I will give that a test. If no one is there, I usually stay 30 extra minutes to charge to 90%. The highest I've had with QC is 93.5%SOC. Most of the time it's around 90% after setting the QC the second time to 100%.

Very interesting information LEAFfan.
You’re saying the Blink QC does not charge the LEAF to the requested % Charge?
I questioned this strange behavior in a separate thread:
http://www.mynissanleaf.com/viewtopic.php?f=43&t=8212" onclick="window.open(this.href);return false;
The time I charged from 77% to 100%, took 25 minutes, the LEAF was fully charged to 12 out of 12 bars.
Both of the LEAF charging times were set to stop at 80% charging. But the different result when requesting 80% from the Blink and 100% from the Blink seems to indicate the LEAF charging timer only controls L1 and L2 charging. Correct?

 

[TimLee]

So are they simply lying? Because the last 20% cannot be possibly charged in 10 minutes, can they?

Blink QC from 77% to 100% at Cleveland, TN took approximately 25 minutes.
Clarification Edit: The Blink QC said 77%. LEAF was at 80% when started about 16 mile drive on Interstate at high speed. Probably was at 8 out of 12 bars. Appears to me that Blink reading of the LEAF % charge is wrong.
More than 3 times as fast on that increment of charging as L2.
So low low battery warning to 100% using QC is probably more like 1 hour, and that is probably dependent on battery temperature you start with and ambient temperature.
I don't think they're lying. The duration they list for QC is just inaccurate.
Their comparison of durations on L1, L2, and L3 needs to be corrected; with clarification of the starting point and end point.
The QC time they list is more like low battery warning to 80%, which is not the same basis they have used for the L1 and L2 charging.
A long trip on the Interstate will be possible with the new QC stations. But overall average speed will be more like 40 mph, which is the top average speed that people could get PRIOR to the construction of the Interstates.
Some people will do it. But most will never travel further than 150 to 200 miles in one day in the LEAF.

 

[klapauzius]

So low low battery warning to 100% using QC is probably more like 1 hour, and that is probably dependent on battery temperature you start with and ambient temperature.
I don't think they're lying. The duration they list for QC is just inaccurate.

I think the difference between claiming from "depleted" to "full" in about 30 minutes and factually 1h is no longer in the range of "inaccurate". If there is no way you can
charge the car to full in 30 minutes as they claim, then they should not make such statements. Maybe its the Blink that cannot do it?

 

[TonyWilliams]

The car takes a bit less than an hour from zero to hero with a full power DC charger (100% added).

It will pump in 48kW and start ramping down that amount all the way until the battery is full, therefore, YOU CAN'T JUST ADD THE VARIOUS CHARGE TIMES TOGETHER.

From LBW to 80%, about 25 minutes (about 63% added).

From dead to 80% in maybe 35-40 minutes.

So, that last 20% can take about 15-20 minutes. Naturally, all these times depend on the temperature of the battery.

 

[DaveEV]

Clarification Edit: The Blink QC said 77%. LEAF was at 80% when started about 16 mile drive on Interstate at high speed. Probably was at 8 out of 12 bars. Appears to me that Blink reading of the LEAF % charge is wrong.

The Blink is probably reading the actual battery % from the battery ECU so the percentages are based on 24 kWh being full - as such it will never indicate more than about 95% when the car tells it to stop charging.

 

[TonyWilliams]

Clarification Edit: The Blink QC said 77%. LEAF was at 80% when started about 16 mile drive on Interstate at high speed. Probably was at 8 out of 12 bars. Appears to me that Blink reading of the LEAF % charge is wrong.

The Blink is probably reading the actual battery % from the battery ECU so the percentages are based on 24 kWh being full - as such it will never indicate more than about 95% when the car tells it to stop charging.

Yes, the data all comes from the car. The car tells the charger how much voltage, amperage, etc.

 

[klapauzius]

The car takes a bit less than an hour from zero to hero with a full power DC charger (100% added).

It will pump in 48kW and start ramping down that amount all the way until the battery is full, therefore, YOU CAN'T JUST ADD THE VARIOUS CHARGE TIMES TOGETHER.

From LBW to 80%, about 25 minutes (about 63% added).

From dead to 80% in maybe 35-40 minutes.

So, that last 20% can take about 15-20 minutes. Naturally, all these times depend on the temperature of the battery.

It makes you wonder why Nissan is being deliberately generous with the information they put out about the car, painting it rosier than it actually is....I would read their claims as being able to go from 0 to full in ~ 30 m.


But still, I have driven the car 50 miles from 80% and did not get an LBW.
Consequently, I can recharge another 50 miles in "about" 20 minutes. At 48 kW charge rate (say 16 kWH in 20 minutes) and an assumed charge efficiency of e.g. 88% (actually direct DC should be better than the onboard AC to DC charger?), this would mean an average mileage of ~ 3.7 M/kWH, which is totally doable.

So a 250 mile trip (on flat land) could be done with 80-100 minutes overhead (compared to an ICE).

 

[edatoakrun]

klapauzius

So a 250 mile trip (on flat land) could be done with 80-100 minutes overhead (compared to an ICE).

I don't think so. Best case, as I reckon:

Start with 100% charge, drive 250 level miles at 75 mph with no heat or AC, on a warm (21+ kWh battery capacity) day, and arrive just before the turtle does.

Adds up to about 2 1/4 hours longer trip time, than the 3 1/3 hour ICEV trip, with the bladder-busting driver.

"TonyWilliams"

...From LBW to 80%, about 25 minutes (about 63% added)...

Sorry, but using Tony's numbers above (which, for a change, I haven't the experience to question) I figure about 110 minutes of charging, for a 75 mph constant driving speed, requiring 5 charge stops, none much less than 30, nor much more than 40 miles apart, except for the first sixty-something-mile and the last 40-something-mile, segments.

Add the time required for 5 exits, the plug-ins, return to freeway and accelerate back to 75 MPH, maybe 5 minutes average, for each charge?

My total is up to 135 minutes.

If you drive a little slower, I think your total trip time would be only about 10 minutes longer (and you’d save about 5 kWh), at about 70 mph, with 4 recharges, if all were available very close to 45 miles apart.

You may want to check my math...

Goodnight.

PS, back OT.

Just a guess, but I doubt you'd have a serious hot battery problem, with the drive above, unless you tried it on really hot day.

But, w/o AC, and with all the windows rolled up, it might be pretty unpleasant for the driver, at the same temperature.

 

[Herm]

for a 250 mile trip:

start at 100% drive 55mph for 90 miles, 1.64 hours

charge for 30 minutes to 80%, drive 80 miles, 1.45 h + 0.30h

charge for 30 minutes to 80%, drive 80 miles, 1.45 h + 0.30h

total 5.54 hours

 

[TonyWilliams]

250 miles at 75mph with ICE (assuming doesn't need gas) = 200 minutes
******************************************
250 miles at 75mph with LEAF and perfectly spaced quick chargers.... 307 minutes

Drive 53 miles to LBW (you can't plan trips to empty, just not practical) leaves 9 mile reserve on nice warm day with no A/C, traveling at 1.25 miles/min = 42 minutes (42 minutes, 53 miles)

Charge #1 / plug in / park from LBW to 80% = 35 minutes (77 minutes, 53 miles)

Now, I can drive 44 miles at 75mph to LBW = 36 minutes (113 minutes, 97 miles)

Charge #2 / plug in / park from LBW to 80% = 35 minutes (148 minutes, 97 miles)

Repeat 44 miles................................................................(184 min, 141 miles)

Repeat charge #3 event...................................................(219 min, 141 miles)

Again 44 miles.................................................................(255 min, 185 miles)

Charge #4.......................................................................(290 min, 229 miles)

21 miles (are we there yet? YES !!!)..................................(307 min, 250 miles)

 

[edatoakrun]

Well Tony, you confirmed my estimate of BEV charge time I posted last night, and even managed to beat my calculated BEV charge time by a few minutes, apparently by assuming longer charge sessions (and one less, 4 rather than 5) could achieve about the same near-optimal rate of charge, you posted yesterday, for shorter 25 minutes recharge sessions.

But where your time estimate is entirely unrealistic, IMO, is that you seem to believe that you can exit the freeway, drive to a QC charge station, get out of the car, plug in add initiate the charge, unplug and return to the car, drive back to the freeway, and accelerate back up to 75 MPH, in precisedly 0 seconds, and repeat this feat 3 more times, during the trip.

In fact, the time required for those actions, will probably be the greatest total-trip-time variable, for any BEV driver planning a multi-charge trip.

And probably a significant annoyance to consider, for many drivers, when making the BEV-or-ICEV trip decision, as well.

250 miles at 75mph with ICE (assuming doesn't need gas) = 200 minutes
******************************************
250 miles at 75mph with LEAF and perfectly spaced quick chargers.... 307 minutes

Drive 53 miles to LBW (you can't plan trips to empty, just not practical) leaves 9 mile reserve on nice warm day with no A/C, traveling at 1.25 miles/min = 42 minutes (42 minutes, 53 miles)

Charge #1 / plug in / park from LBW to 80% = 35 minutes (77 minutes, 53 miles)

Now, I can drive 44 miles at 75mph to LBW = 36 minutes (113 minutes, 97 miles)

Charge #2 / plug in / park from LBW to 80% = 35 minutes (148 minutes, 97 miles)

Repeat 44 miles................................................................(184 min, 141 miles)

Repeat charge #3 event...................................................(219 min, 141 miles)

Again 44 miles.................................................................(255 min, 185 miles)

Charge #4.......................................................................(290 min, 229 miles)

21 miles (are we there yet? YES !!!)..................................(307 min, 250 miles)

 

[TimLee]

Everyone is also failing to recognize the time to get ICE vehicle removed from the Blink QC location.
When I used the Cleveland, TN Blink QC at Sunday lunch rush, both spots at the Blink QC had ICE vehicles in them.
Cracker Barrel was very helpful, and proceeded to page both vehicle owners.
But a full Cracker Barrel is fairly loud.
I think they had to page 3 or 4 times before one of the ICE vehicle owners heard the page and came and moved the vehicle.
Took about 30 minutes before I could get into the spot to start the QC from 77% indicated by the Blink QC (probably 8 out of 12, 67% on the LEAF) to 100% which took 25 minutes.
More than 100% overhead time in getting ICE vehicle moved.
It still appears to me that the Blink QC software that reads the LEAF info is erroneous.
I'll have to try the Murphy Express Eaton QC sometime to see if its the same, or has correct software.