Friday, May 11, 2018

April 11th, 2018; A Day That Will Live In Infamy







Ok, I admit I stole that line from somewhere... but an event of monstrous proportions happened that day regarding my LEAF and the aim of this entry is to get to the bottom of the issue. If you recall my April 2018 driving log, I was well on my way to an acceptable level of degradation (less than 3% over 3 years or 1% per 5,000 miles) on my nearly new 40 kwh LEAF until... well the morning of April 12th when I woke up to this.


Overnight, I lost a chunk of battery that normally would have taken me 7000 miles to lose using the same trend line that matches the rest of my 5600 mile LEAF life!  With this humongous overnight drop, I have still only lost 1.43% so far.  This despite several multiple QC days, baking the pack to 120ยบ plus, etc.  The decline has been daily but very very slow.  But remove this one day hiccup and assuming first bar loss at 80% SOH, I was projected to lose my first bar at 167,164.2 miles!  This was.... "acceptable" but with the drop (and not enough time passed to overcome the day) my first bar is now slated to drop at 78,321.7 miles.

Below is two graphs charting stats over time and one for miles.  As you can see (ignoring Hx which has simply gone off the charts) the trend lines are nearly flat minus the one day.  Notice the dip in SOH around 2000 miles? That was a SW change to recalculate SOH on LEAF Spy that did not work out so was returned to the previous method.  I have to think the previous method was the same used by hundreds of LEAFers over the years. Data that has all but been proven to accurately reflect the health and capacity of the LEAF battery pack.



To The Logs!

Well the first thing to do was examine logs from April 11th and 12th to see if anything stood out.  Did I bake it once too many times? Did I hit a new temperature high?  Would the effects of such actions manifest themselves immediately or would they take a few days?  It was these questions I hoped to shed some light on.

April 11th

The day seemed normal. As always, I record LEAF Spy stats daily first thing in the morning before doing any driving.




FYI; My elevation is closer to 50-90 feet above sea level (No my neighborhood is not flat) . For some reason, GPS works like crap while in garage...

But everything is pretty much as planned. I don't charge to full when I don't need it and the day was normal in that I parked the LEAF overnight at 68% SOC... (Notice I still have the nearly full range of a 30 kwh LEAF?... That is not an accident.  ๐Ÿ˜Ž)  The battery pack temps are over ambient which means a QC happened on the 10th.  Normally at that time of year, pack temps would be in the low 60's. 

I then stopped for a QC @ 30% SOC  (152 GIDs) hitting 120 amps pack temps at start;  73.8/69.6/65.5.  Charged to 69.4% (351 GIDs) pack temps;  100.0/97.9/90.6.  

Drove a little bit then QC'd again starting SOC; 64.2% (324 GIDs) starting batt temps; 99.8/96.8/89.6
hitting 83 amps.   Ending;  91.9% SOC, 464 GIDs,  Batt temps; 106.0/102.7/94.2. 

Eventually arrived home with 79.9 % SOC, 404 GIDs,  Batt temps; 103.8/100.0/90.6.  Ending ahr; 114.3086,  SOH; 99.02, Hx; 115.25. SOC was higher than my preference but canceled plans for later that day was the reason otherwise the 2nd QC would have been quite unnecessary. 

April 12th.

First thing I realize its one of those "days" where LEAF Spy is only running a bit in the morning and for QC sessions.  So there is a HUGE gap in time and...well, yeah we already know what that means. What we were looking for happened during that blackout period. 


So I leave home at 5 AM and stop to charge at 5 PM.  Notice pack temps have cooled considerably. Guessing near ambient which means parked somewhere probably all day in the shade!  The log was ended before I got home but the single QC of the day did little to heat the pack. 


But the damage was done. The new baseline was 98.43 % SOH.  This I had to accept. 

The Horizon

All is lost!!... well, actually that might not be completely accurate.  The massive drop in battery health has hardly put my pack on the DL.  What it did do is;

**Failed to make me "QC adverse" since I have quick charged 11 times in the 29 days that have passed. 

** Failed to make me "Heat Shy" since I did journey to Ellensburg in Central Washington a trip of 353.2 miles where the afternoon temps hit the high 80's.  May not seem hot to most but in full Sun (required due to incompatible QCs of Aerovironment forcing me to L2 for several hours) it was baking.  OAT registered 93ยบ on return to car after basking in hum of Arby's AC.  And my sprint to Tacoma from North Bend did cause a near record high of 121.5ยบ batt temp. 

Now extrapolating 29 days of data into a 100,000 mile projection is more than a bit crazy BUT... I got used to being called that so... 

Since "The Day" I have traveled 1080.1 miles losing .18 ahr, .15% SOH while gaining Hx (as usual) This puts my new "Bar Retirement Day" at 106,280.4 miles.  Again, this will be acceptable to me realizing this puts me a few miles over the range of a new 30 kwh LEAF.

BUT...

This is somewhat disappointing as it likely means I will miss my chance of getting a free warranty replacement of a new improved battery pack a few years down the line.  

I knew this car wasn't perfect.  

Friday, May 4, 2018

April 2018 Drive Report; I Think We Are Alone Now





The monthly drive report has morphed quite a bit over the years. My blog was never intended to be public. It was essentially a group of notes on my transportation costs recorded for use on various online sites, a diary more than anything dating back to Thanksgiving 2003 7 months before the arrival of Prius #1.

My monthly logs started out comparing the cost of my Prius to the "average" car. Then it was my two Priuses, then the Prius and the ZENN, Prius and LEAF,  LEAF and Corolla, etc.  During my time at RGIS, it morphed again into a very interesting "Gasser verses EV" contest due to a very heavy driving schedule that illustrated a shifting balance dictated by an ever increasing range, more public charging and simply a shrinking need to use gas. But that job is no more. There was just too many obstacles including massive road construction projects that would have greatly impacted my day.  That combined with the fact that my job was hardly coveted meant it was simply time to move on.  So that reason along with the much more useful 40 kwh LEAF's range meant the Corolla's time was done.


So now I am down to one.  So comparisons against "phantom facts" is not something I can participate in but mostly because I constantly chide and challenge others who do the same thing.  This morning from Green Car Reports;

What kind of car are you driving? It costs me about $30 to put diesel in my 2015 Golf here in Florida and that is good for 600 miles under typical highway 75 mph conditions. I am 100% certain that I would be saving no money using a fast charger and travelling under equivalent speeds and conditions.

This is THE reason why this blog exists. I record the data. Anything you see here comes from personal observations (which can include personal conclusions) or data logs (mostly from LEAF Spy) but more importantly,  its not a "seat of the pants" estimation.   The person above is claiming 5 cents per mile and I have no doubt he attained that figure a few times but claiming that this is normal?  Maybe a few months ago when gas prices were lower?

Back in the early days of LEAFdom (driving my ZENN around created more laughter than curiosity...) I had a lot of interested people come up to discuss why their gas so and so was a better fit for them and the logic employed was frequently both comical and mathematically impossible.  But what proved to be the more difficult challenge was showing how their thought processes were flawed.  I realized I was not going to teach the World to change, I had to do it by example.  So the monthly driving log lives on only to show what can be done since I actually did it.  Can you duplicate (or even possess the desire) what I did?

Maybe, maybe not.  You could easily do better. My days of driving carefully left soon after I got my S 30.  The teeny tiny range boost was shockingly liberating.  Sure, I had challenges, but I also had several days when I knew I would be getting home with several miles to spare no matter how fast I drove so I broke the law.  I can honestly say that in the short 2½ months I have had my 2018, I have easily exceeded the combined total of miles driven over 70 mph in both my 2011 and 2013!

Any way, on to the stats!  My LEAF traveled 1876.6 miles costing $13.44 or .7 cents per mile.  Public charging usage totaled 340.55 kwh costing me 61 cents (Blink overruns) Without that benefit, I would have paid $45.09 or 2.4 cents per mile.

My battery stats finished lower again with ahr; 113.43, SOH 98.26% and Hx still lofty at 115.90%


monthmilesahrSOHHx kwh
Day One24115.0599.6699.8638.5
Feb 2018866.7114.9199.54106.9538.2
Mar 20183292.6114.4799.16115.7538.2
Apr 20185168113.4398.26115.937.8

Obviously hard to extrapolate much from this limited data set.   I guess I should add a few columns; % lost since new.  Now what is considered the most important of the stats is an opinion expressed by many so I will express mine and say that I have lost 1.4% of my ahr potential in 5,000 miles which equates to under 9% at the end of my 45,000 mile lease. That is ok, I guess.  I personally think 5% considering the much larger pack size is more appropriate but I guess we will continue to monitor and see what happens.  Summer has yet to arrive and yeah, I have baked my pack over 115ยบ just under 20 times but that probably didn't do much. 

I will say I had one LARGE drop that I cannot explain. Nothing unusual around this time I can think of but before that ONE day, I was well on my way to about 5% loss in 45,000 miles which is very much ok.  


4/11/201898.24.5114.3199.02115.25
4/12/201868.94.2113.5598.36115.57
Up until that one day, the drop has been consistent but very gradual and no, I have not gained back anything so maybe it was a "pack adjustment?"  I am guessing there is something here but just not seeing it yet. I will be looking at this more for sure. 

Monday, April 30, 2018

Road Trip With Altitude!

So everyone has read my previous road trip adventure that came complete with multiple QC options and relatively flat terrain, right?  Well that was hardly challenging. In fact, it was quite stress free other than the lack of stops because I didn't have to!

So I decided something a bit more challenging was in order and that was a 3000 foot climb to the Wild Horse Wind and Solar Complex outside Kittitas, WA about 170 miles away.  Now due to AV incompatibility with my 2018 LEAF, the QC luxury was not going to be an option on this trip. I already knew that several hours or L2 would be in order so the challenge became how to incorporate all that into the trip.

The Plan;

I would leave with a full charge driving to the North Bend Premium Outlets and the EVGO QC there.  Get a charge to at least 90% then hit Wild Horse which had Level 2 options available where I would plug in for the time I would be there which I estimated to be roughly an hour or just over then drop down to  Ellensburg, Home of Central Washington University and to several level 2 charging options where I would park downtown and take a walk around the town to grab lunch. I figured on close to 2 hours or so for this and that should get me enough to make it back to North Bend to QC again.

The Drive;

The batteries were warmer than I had hoped for. All week long, I was in the mid 60's due to my shorter commutes combined with no fast charging but I did do a fast charge at Tacoma Mall the day before so I started with batteries warmer than I wanted but also realized that the slowing of the charging speed starts in the 90's so I am good!   Batt stats aren't as high as I would have liked but realize this is first full charge Since March 29th so a good top balance was not expected or needed for the first leg.





I had missed the super warm weather we had had all week long but Ellensburg promised temps in the mid 80's so near perfect walk about weather but soon after I hit Highway 18, it started to rain.  It was a mild one generally with a few stretches of rain hard enough to actually get you wet but all in all a pleasant drive with CC set to 65 mph.

I was tracking my batt temps knowing I needed to be no more than the low 90's to get a full speed charge from EVGO and just as I hit the Highway 18 to I-90 jam up (its always there...) I had been on the road 102 mins and battery temps were at 89ยบ  after 58.3 miles averaging 56 MPH which was great time.   I pulled into North Bend with batt temps at 92ยบ which meant I was golden!!  But the elevation of North Bend is only about 450 feet so I still had over 3000 feet to climb so getting a good charge was paramount. 





QC Charge rate declination starts in the 90's ยบ F and its pretty steep.  In the low 90's, you will see all that the station can provide.  I started here at 121 amps but with the high SOC so the rate starts to drop right around 58-65% (temperature dependent) as expected but still able to leave the station with SOC over 90% and 145 miles on GOM.  Here is a GREAT example of the knee that happens when the  LEAF hits 90% SOC.   Charge time; 30 mins,  14.08 kwh gained.

So off I went to make the climb and climb it is!


Still maintaining roughly 65 mph as much as possible. It was Friday and the traffic was heavy plus there is the perpetual road construction going on but traffic flow was good with only a few slowdowns into the 50-55 mph range.  Although I had plenty of range to make it to Wild Horse, I got a nagging feeling that I should be preserving range so after summiting the pass, I decided to lower my speed to 63-65 mph to collect a little regen before the big climb ahead. I now only wish I had decided to do that sooner. 

Wild Horse;

I got the Wild Horse and all was good.




The temps were actually in the mid 70's so not sure what LEAF was thinking but maybe the 30-35 mph winds were confusing her?  Definitely a great place for a Wind Generator! In fact several of them!


You will have to click on this pix to really see what is going on but the red approximates the pix above but notice the purple square in the upper left corner?  This complex is HUGE!!


Hard to show you what 35 mph wind is like but at least you can hear it! 

But my joy at the awesome display of how green we can be if we want to be was soon tarnished.  Wild Horse has several places to plug in including 14-50 outlets so I brought my trusty (and tested successfully)  EVSE with me and plugged in and it started to charge!...or so I thought. The lights came on for a second but after about 5 seconds, the EVSE faulted.   Well, that sucked but there were 2 more to try and... no dice!  Well after checking several things including error codes and finding nothing, I went inside to ask if the breaker needed to be turned on since that is what the instructions on the breaker implied and both hosts looked like Deer in the Headlights kinda thing.  Well, they called around and determined that the breakers were always on and finally ponied out their EVSE that hooked up to the 6-50 Outlet.   I was able to plug in and charge on that at 5.3 KW but the whole process lost me about 20-30 mins of charge time.

But I had contingencies in place and the place really was amazing!

 Solar Powered Ferris Wheel. I sooo wanted one!! But this was the only one there and guessing
it probably wouldn't take long before they noticed it missing



Despite its heft, this turbine can be spun by hand. It takes a bit
 to get it going but it will spin for a few mins 



These transformers are pretty decent size!
Seeing the parts of the generator at ground level was astounding because the reality is they are so tall even when standing under them, its hard to understand the true scope of them


Despite their size, the edges are actually pretty sharp!



After a great walk around the area (past signs that stated "No Public Access") it was time to unplug and head for lunch.  It's a steady downhill all the way to Ellensburg so planned to have more than half of what I needed by the time I got there so off I went and as I pulled into the lot where the charger in the middle of downtown (and lots of food options) was, I immediately felt that my day was to become challenging...very soon. 


One thing I always tell people is review check ins on Plugshare to insure that the charger you plan to use is in good shape because a lot the ones listed are simply not functional and most of the ones in Ellensburg are non functional.  The one downtown had a good check in a week prior so I was confident I would be fine.  And don't get me wrong, expanding to add plugs is a great idea but do you have to pull out the one that works??? WTH! 

There are only two others within reasonable walking distance to downtown but decided against wasting my now precious electrons on them for some reason...



This was a bit of a disappointment. There were still other options but I had several recommendations for good food in the area plus it was now becoming a time factor. In desperation, I pull up to the last option likely in Ellensburg and I found this


To make it worse, there is no lights or any indication of life whatsoever but I plugged in anyway... and it worked!  5.8 KW!  But now I was stuck on fast food row.   A quick glance up and down the street did not reveal anything tempting. There was a Mexican food restaurant with a very large parking lot that had one single car in it. Guessing its reputation was built on the drinks they served at night more than anything.  After 4 blocks or so, I eventually stopped at Arby's and was pleasantly surprised that they had Gyro's and they were 2 for $6.  Well, not expecting much, I tried them anyway and they were actually pretty good!    After eating, I had no intention of running back to the car since I needed close to 2 hours to charge  to make it 80 miles back to North Bend with a pass to summit in between.  

Parked in Ellensburg to charge. Temps would rise to 86ยบ by the time my charging was completed

While sipping water and enjoying Arby AC, I noticed out the window I was only a block away from both a Thai place and Mexican restaurant... Oh well. Missed out again.  To ease the pain, I "forgot" to check Google for ratings...

After about 90 mins of killing time, I wandered back to the car and decided that I needed a bit more so crossed the main drag and grabbed some fruit from the stand.  Got a pretty good deal on Apples and finally back to the car and I had 42% and 93 miles of range.   Sounded good so I took off.  

But it didn't take long for me to have concerns. There is NOTHING on this side of Snoqualmie Pass to charge other than Suncadia which is a 5 mile detour or a total of 10 extra miles. AV has a QC station there that would have made all this drama mute but Nissan has not yet seen fit to replace a resistor to make the 2018 compatible so we continue to suffer. 

Not being totally sure of how my range would affect by the climb and despite my LEAF Spy saying I would have enough range, I decided to stop at Suncadia after all.  As luck would have it, a Honda Clarity was parked in front of the DCFC not using it so it sat there grinning at me as I plugged in the Level 2 at 5.9 KW... Worse yet, with batt temps at 102ยบ, I would have had about 2/3rds max power...

I had thought about walking around Suncadia a bit since I had never been there but the wind was treacherous and worse than Wild Horse, I had to struggle just to get my door open to plug in.  The car was rocking so much with the gusts, I honestly thought I would get sea sick... But instead it rocked me to sleep.  I napped for a short period of time and unplugged just at the one hour mark. 

I now had way more than enough charge to make it to North Bend. 


Ok this graph needs a bit of explaining. (notice the temp bar disappeared?) For one, the time line is off.  North Bend charge started at 91 amps (88 amps on LEAF Spy but had to keep car on or LEAF Spy would lose focus)  which starts to the left of the 4.5 hour timeline. Starting temp was 101ยบ ending at 113.3ยบ.  Charge started at 32 KW ending at 31 KW so obviously a charge controlled by starting temperature since SOC was low enough to not play a role.  30 min charge,  15.49 Kwh gained. 

Now I was home free! Well, sort of. The lateness of the day along with charging frustrations had eroded most of my patience so instead of tooling home at 65 mph, I basically weaved in and out of traffic on Highway 18 at 70-80 MPH which saved probably not a lot of time but raised my batt temps to over 121ยบ and despite it being an elevation drop.  Despite the temps dropping to just under 120ยบ by the time I hit Tacoma Mall, I already knew i would be getting a SUPER slow charge. 

In fact it was so slow, my batt temps DROPPED to 118ยบ!   I started the charge at 61 amps (20.6 KW) finishing at 58 amps.  Charge time 30 mins, 10.86 Kwh gained. 

Then home.  



Synopsis; 

There are a lot of ways I can take this.  This trip hardly went off as planned and the missteps by me and the network all caused delays.  But I did not get stranded so as long as you have time, you are good.  As long as you have chargers, you are even better.  So I can't blame the LEAF especially since I have already made the 3 year lease commitment and that would mean I made a mistake which as we all know, can't be true!  

I took this trip already knowing it would be a long day of waiting while my car sipped electrons from a very VERY small straw.  I already knew that the unfamiliar territory of incompatibility would make this and potentially any other trip a challenge.  So did this when I knew I had plenty of time to kill.  

But the real problem is the lack of public charging infrastructure beyond the Western Washington metro areas.  On my return while charging at North bend, there was a Bolt charging getting ready to go over the pass and the lady was concerned due to lack of CCS heading East so the knee jerk reaction of getting a car with more range is not going to work either. 

Luckily Washington's soon to be restarted West Coast Green Highway Project will have Central WA as a focus point for station deployment and it couldn't come too soon and yes, they will be dual format so even Bolters will have cause to celebrate. 


Takeaways

Speed kills especially going uphill at 70 mph. My pack was already hot (113ยบ) but got hotter and LEAF Spy logs shows several hits in the 60-70 KW range which likely happened going uphill. 

I should have saved elevation pix between each driving session  since the CSV file did not come out as expected.  A better shot would have been the sprint from North Bend to Tacoma but unable to create any graphic from the data I got...  Next time. 

Elevation Profile from Wild Horse to North Bend

Compatibility would have helped a lot.  Not wasting time with trying to figure out why my EVSE wasn't working, etc. was significant.  This is likely the reason I had to make an unplanned stop at Suncadia although I must admit I didn't mind taking a look at the place and a walk would have been wonderful (if the wind had been under 35 mph that is!)  This will become a very serious issue for many come Summer when heat will play havoc with charging temperatures especially in Oregon where AV has a huge presence. 

The pack temps did not heat up nearly as bad as I expected them to especially on the climb from Ellensburg to Wild Horse. Mind you, over the pass the temps immediately jumped 20ยบ but the LEAF did just fine driving 60-65 on I-90 and 50 mph on the road to the farm (which was speed limit) I was surprised to see a temperature rise of just a few degrees never getting over 102ยบ.  Even later in Ellensburg when temps surpassed the mid 80's the LEAF did well.  I will say the steepest part of the trip the roads were the twisty kind and speed limit was 25 mph which was a good thing. It would be easy to go up at 35-40 mph (which I did) as long as road was empty but going down, 25 mph was the place to be.  But even the climb to the pass on I-90 from the steep side (see above) at 60 MPH did not heat the pack at all and most of that climb was the low 80's to the upper 70's with a LOT of side winds. 

But again this proves that the LEAF is a smack dab in the middle of the "Medium" range EV class and that goes for road trips as well.  Regional travel is a piece of cake simply because you have 160 miles of range leaving your garage so its a simple thing to plan stops where you can grab a boost.  Right now there are a few places that do not have convenient QCs on the way there but that will change beginning this Summer or sooner (if Nissan gets on the ball)  so again, I say 250 miles is easy.  350 miles like I did Friday "will be" easy when the AV issue is cleared up but for others who do not have a good QC coverage, plan on some down time since recharge times will exceed to boundaries of  normal breaks/rest times from driving.  IOW; go somewhere where there is something to do!  But then again, isn't that why we take the road trips in the first place? 

Finally the other thing to "re mention" is throttling of quick charging which can be severe in severe situations like my 120ยบ charging at Tacoma Mall Friday at the end of the trip. 

But realize this situation will be more common come Summer.  Excepting the few areas where ambients reach that temperature neighborhood,  only the 2nd QC will hit that range but the previous 2 QCs is something that most of the country will on their FIRST QC so instead of getting that 100 or 120 amps, you will be getting 80 or 90 amps (depending on top speed of the station) which means not getting 20 kwh but getting 14 or 15 kwh.  

Realize that is only 60-70 mile bump in range. Add some destination charging and this is how I come up with the 250 mile statement.  As always YMMV but one thing is clear in all this; Most areas of the country including mine, remain in the Dark Ages of Public Charging support. 


Monday, April 2, 2018

March 2018 Drive Report; 100% Electric!

As mentioned in an earlier blog, the Corolla's role has been shrinking in direct correlation with the increasing range of the LEAF.  With the 30 kwh LEAF, the Corolla's contribution dipped below 4,000 miles a year with probably a quarter to a third of that usage simply to keep the car from sitting too long.

Well, this month I gassed it ZERO miles.  The Corolla is now being used daily by someone who needed it and simply could not afford to buy a car and maintain the expenses. My original plan to give it to a co-worker, a single mother, didn't work out as she realized the additional expense of insurance simply wasn't in her budget.  The thought she would be able to work more and make more money simply was not clear enough to her but I had another co-worker in the same boat who has a work ethic beyond anyone I have ever known.

He was also without a car in a job where 100% of the work is done at client locations so the efforts he put in to making meet times at the office or directly to the store's location was simply awe inspiring! So off the Corolla went!

So for the month the LEAF solo'd it  for 2527.2 miles costing $15.73 in combined home charging and public charging fees or .6 cents per mile.  NCTC contributed "a bit" at  478.185 kwh which at  "home" market rates would have put my cost at $60.20 or 2.34 cents per mile, still a very good way to travel!  But that is "home" rates. Even with EVGO's new reduced rates, the cost would have been a "bit" higher.  Thank you Nissan for that wonderful program!  (Now if you could get that AV situation squared away...)


LEAF Spy STATS

Since the weather is still cool enough, I am ok with full charges overnight at home but still don't have a lot of them but the ones I do have are not consistent. The randomness is getting a bit better though


Looks like a likely baseline would be GID count in the mid 490's,  kwh available somewhat above 38 with SOC in the 97% range.  Still a bit high for my liking.  Its ok now while garage is still in the 50ยบ range...

As mentioned several times before, my ahr and SOH continue their downwards trend while my HX has apparently not hit its ceiling posting a new high this morning of 115.75%  Again, no alarms yet as the drop in stats is hardly steep or alarming as of yet.  If I were to extrapolate my SOH loss over the 44 days I'd had the LEAF, I would be losing 3.85 % a year. I guess the big question becomes is my loss faster on a new pack or would it slow down? My previous packs sat at full stats anywhere from 8 months to 1½ years before showing any decline.  The diverging SOH/Hx issue is also a bit strange.  Stay tuned.

Aerovironment  AV
As mentioned, the AV QC is not compatible with the 2018 LEAFs... well, sort of.  We now have confirmed reports that Lincoln City, OR,  Bellingham, WA and Castle Rock, WA do work! So does this mean AV has started the fix?  Probably not.  It would appear that the AV network is simply inconsistent.  So this means we need a call to arms!  We need volunteers to go to each AV QC on the network and test their 2018 LEAFs and report back here and on Plugshare!

Quick Charging


Lots of talk over "QC Gate" where the LEAF is slowing its fast charge rate way way down as temps rise.  We even have one in Arizona already seeing 22 KW charging speeds on her first QC stop and its only April!  This Summer will not be good for her!  As for me; temps seem likely to play a part and determining the effective range of the LEAF with public charging come this July should be interesting. I am guessing 250 miles with one fairly decent QC.  I did a QC on Friday starting with batt temps at 105ยบ and got a respectable 109 amps (of 124) and over 20 kwh in 30 mins. That is something I could easily live with.   My bigger concern is the early ramp down.  I only got 20 kwh due to very low starting SOC.  On LEAF it was "_ _ _"  but LEAF Spy said 8%...

Yesterday, I hit the QC and started at a full charge of 124 amps and got 22.4 Kwh but still saw the ramp down at the end of the session for the last 3 mins. Not the end of the World but with my pack at 112ยบ, I needed a few hours of parking time to be able to get another QC at a decent speed.  Now the pack does seem to cool off when its real hot but the cooling rates drops off considerably in the mid 100ยบ range.  This makes it a 50-50 chance of another decent QC.

This will add another level of trip planning to the mix. Now, estimated battery temps along with SOC will be critical if a tight schedule is needed.  I don't do trips IN ANY CAR with a strict time schedule. Traffic is simply too unpredictable here. So yeah, I arrive an hour or two early..."sometimes" but I am ok with that.  Being on time has been a lifetime priority for me.

I have started collecting data on QCs for another blog entry.  I am waiting on a chance to do more of a continuous run.  Right now,  my driving pattern is mostly drive 40-90 miles, park it to work, then return.  Too much time to cool off in all that.  I have a trip I do to Salem OR area every year and the extra range of the LEAF means I can ignore AV and just do Blink and EVGO for the trip quite easily. I think I am going to wait for a warmer Sunny day for that. I hope to do that trip within the next few weeks though.

Random Observations
Anyone notice Blinks are working?  Guessing most of you don't since you wrote them off a few years ago like I did.  Then Blink changed their name... again.  Kinda wrote that off as well.  But things started happening.  The Hoyt Road Walgreens QC, broken OVER 2 YEARS...maybe 3, was fixed!  In fact, nearly every Blink QC is working now.  Well, I happened to run into Rick and Julie from Durst Energy at Tahoma Market last weekend. They are the people hired by Blink (and other public charging companies) to maintenance the stations.   They said the calls from Blink are on the uptick!  This couldn't have happened at a better time.

EVs are quickly moving up to a newer and wider level of acceptance which means competition for that plug is set to get intense!  Our planned QC buildout is slow, underwhelming and is already insufficient to handle what I see as a banner year for EVs in WA.  The VW settlement is looking to be too late and too little when it does get here to matter.  We need someone to step up big.  One or two stations is not going to work here anymore. We will soon be way beyond that.

Its Baseball Season again and did you see that catch Ichiro made to steal that home run? It ended up being the game winning play!   Now the reason I mention it is because my previous LEAFs when quick charging, created too much interference on AM radio. But now I can charge and listen to the game!! Life is good.

Thursday, March 29, 2018

Fast Charge Test; Part Two.




On my 2nd charge on March 26th,  started charge at 35.97% SOC,  B temps, 93.8/91.0/84.0, starting 120 amps.  OAT  50.9ยบ

110 amps;  63.77 % SOC,  B temps 111.5/109.7/98.4
100 amps;  66.64% SOC   B temps  112.7/111.2/9934
90 amps  ;  70.41%  SOC B temps  114.3/112.5/100.4
80 amps  ;  74.09 % SOC  B temps 115.3/113.5/101.3
76.9 amps; 75.43 % SOC  B temps 115.6/133.8/101.8


3rd charge;  started 69.89 % SOC,  B temps 114.0/110.7/99.2, OAT 49.4ยบ

     SOC       KW            volts          amps      Batt temps
698879 21.687 372.67 -58.196 114 110.7 99.2
720557 21.617 376.99 -57.342 114.3 110.9 99.2
825470 21.674391.1 -55.419 115.1 111.7 99.2
851834 21.376 394.18 -54.229 115.1 111.7 99.2
891454 20.553398.98 -51.513 115.6 112 99.4

The above was the first part of my data collection to add to my first blog about charge speed.  Well, you can ignore all that.  Its not valid.  The data is real enough but its not what we need to concern ourselves with.  That is the conclusion. Now for the rest. 

Ideology

Previously my concern with lease miles and the multitudes of opportunities to drive a lot for work controlled my experimental parameters.  But after several multi QC days, I started seeing a pattern. One I had to confirm and the only way to do it was to do a trip like other people do trips.  

In my work day, I would charge once in the morning, drive 30 to 100+ miles, work, then drive a bit, stop and charge and go home. This is not how people travel and I also noticed that charging speed was not dependent solely on SOC OR battery temperatures.  So I could post 5X more of the above to show the inconsistencies or not. 

So I decided to hit the Outlet mall in Woodburn OR. I  generally go there 1-2 times a year. I always plan to do it on a good weather day since its a long drive and I need to stretch my legs which I do while the car is charging and I'd rather stay dry if possible.  So this would be a 155 mile trip one way with layover of less than 2 hours (one hour and 12 mins actually) with an immediate return to Olympia.  IOW, a trip driven like "you" would drive it.   Now we could look at it as a 300+ mile trip which is near the length many would drive in a day in an EV anyway.  I would aim for 400 but didn't have a reason to go farther South or I would have done that too. 

Start

The goal was being both realistic and consistent so whenever possible, I set cruise control to 65 mph. To make the timer realistic, I decided to let the car run all the time while charging other than the brief periods I have to shut it off while initiating the charge.  I was also going to test AV stations in Ridgefield and Woodburn and you know how lllllooooonnng it takes for them to start up so I added 10 mins of idle time to the clock. Despite my best efforts to record everything, I somehow missed a few pix... lost somewhere or sent to wrong place? I will add them when I find them.  But I also recorded the data so info is still provided. 


Notice the 173 mile estimate? Well, We shall see. I set LEAF Spy to 4.0 miles per kwh
and it says 158.6 miles and no, Kwh available  multiplied does not correlate. 

This  was my first full charge in several days so I was not expecting a good pack read and LEAF Spy did not disappoint.  From log;  488 GIDs, 37.8 kwh available, 96.57% SOC.  Temps 70.9/65.5/63.6  anbient 57.2.  Previous QC;  4/5/18 end 2 PM. Unlike my 30 kwh LEAF which cooled to ambient in 12-14 hours , this one has "carryover" heat!  

GOM Verses LEAF Spy!

Ok, so this was going to be a LOOONG trip. I expected to average 50 mph driving which means 6+ hours with traffic, stops, etc. along with 3 planned QCs of 30 mins each but the reality it would be mostly sitting there driving... Boring!  So I had to combine experiments to keep my awake!

As you can see above, the GOM is stating 173 miles and as we now know, there is a rather large reserve as well so does that mean 173 miles plus reserve?? Well, no because the "173" is actually "151" in disguise so its 151 plus reserve.  Anyway, its my contention that no matter what the miles/kwh meter on the GOM says, my static 4.0 miles/kwh to 1% on the LEAF Spy customizable range estimator will be more accurate but both will end up in the same place taking a different route... I guess. 

So off we go! and the GOM holds out well at first. Obviously this pix was taken with the utmost goal of complete safety.  Unfortunately, conditions weren't always conducive to picture taking. FYI; I am not holding phone. Its holder is long enough to bend to this position.  


So as you can see, the GOM starts out well but... 

@ lower SOC, miles traveled/GOM/LS estimate   Batt temps, ambient

90% 18.8 152 141 73 63 65.8 53.8
80% 33.8 137 125 74.5 71 67.3 54.5
70% 45 114 110 77 73 69.6 52.7
60% 61.5 101 97.4 78.3 75 70.5 56.3
50% 76 86 84.4 79.9 76 72.1 56.3
40% 89.3 68 71.3 80.8 77 73.2 55.4
30% 98.6 52 61.1 82.4 79 74.5 57.2
Ahh!!! looks like GOM "lost its lead"  I took the liberty of snapping a shot (about 3 in fact but none really turned out too well but at least you can see most of this one) of the moment LEAF Spy took the lead! 


Anyway, that was a fun little side trip!  I did record batt temps so it wasn't a completely frivolous journey!  It seems every day, I find something different about the 2018. Here I am coasting in neutral about 65-70 mph.  The amount of power shown is... well shocking!  My S 30 would show anywhere from 200-500 watts... 



AV Testing

Well, this was easy. Tried Ridgefield and Woodburn and neither one worked!  So had to sweat it out to Vancouver to charge on Blink at Fred Meyer.  I just barely made it...


Charge Curve # 1

And, as we shall soon see. It will be the ONLY curve of the day. 

Vancouver arrival. Ok, so maybe I had a bit extra range...FYI; LEAF Spy range
estimator jumped. (I probably tapped it by accident) but still showed 
same range estimate as it did at mile ZERO


The only curve of the day!

So plugged in to the Blink and as you know, Blink is the ONLY NCTC provider where you can incur additional charges after your free 30 mins. Blink does not provide a timer and it starts billing at 30:01.  So naturally, I was dinged for 6 cents. 

Charge started at 119.71 amps 34.70% SOC,  finishing at 70.31 amps and 80.61% SOC. 20.31 kwh.  Notice the rather predictable rate of charge verses SOC.  There are two distinct slope changes but the remainder above 75% SOC is rather static.   On this charge, the ramp down started at 63.91% which is about the norm. 


Vancouver Departure



So on to Woodburn with high hopes... (see above for results!)  So naturally now the pack is hot and any hopes of a decent charging speed is all but gone.  So the plan is hit the outlet mall first then charge on way out of town. This is best anyway. Last thing we want to do is boost the SOC, heat the pack then park it!   But!!!

            Woodburn; AV stop (failed) / Outlet 

In the time I was shopping, the temps dropped to "near" the range where I could expect to get a decent charging speed!  It was my hope that maybe I could drop it a few more degrees and the reasons will be discussed later.   But was not to be.  Despite temps dropping to 102ยบ,  the charge at Woodburn failed so I decided to hit Woodland on the way home instead. My objective was to show a "curve" with warm batts but SOC had to be similar and I also wanted to beat Portland traffic (didn't work).  The drive ended up being a lot of stop and go and sprints. Not a good way to cool off the pack plus we had full Sun with temps hitting 70ยบ in Oregon. 



Woodland Arrival 

Not Part 2; Symptom 2!

As predicted in previous blogs, it appeared that a charge rate of 30-35 KW was possible when batt temps were at or just below 100ยบ.   Woodland EVGO did not disappoint.  started at 80 amps dropping to 77 amps which meant a rather static charge with increasing voltage of the higher SOC.  Charge gained 13.87 kwh.  That is 6.44 kwh less than Vancouver but important to note this charger max'es at 100 amps while the Blink did 120 amps so there would have been less charge under any circumstances. 


The Revelation




First thing that should jump out is that despite rising temperatures and rising SOC, charge rate is flat.  This verifies SEVERAL observations I have had where charge rate is controlled by two factors;

Beginning SOC;  This is the obvious one. This is also VERY much unlike my S 30 where the charge rate always started at the full rate of the charger. In cases where the SOC was high, the ramp down started quickly but in most all cases, I was getting full speed for at least a few minutes.  Using the charge curve from Vancouver, its easy to predict the charge rates at various SOCs, right? 

Beginning battery temperature; As we now know, battery temps are also creating their own ramp down curve but it now appears that is ONLY based on battery temperatures at the beginning of the charge.  After the initial charge rate is set, the SOC takes over controlling the remaining charge, hence the flat charging rate. 

To prove the latter, another charge was required.  To maintain temps, my trip to Castle Rock averaged 70-75 mph.  


I arrived at Castle Rock with temps still above 110ยบ but not high enough to trigger a 22 KW charging speed which generally needs to be 114-115ยบ.   SOC 20.82%, 74 amps charge rate increasing to 77 amps finishing at 73 amps. 34 min charge time,  14.23 kwh gained. 


As we can see, again no charge rate curve despite very high temps. It was my plan to charge to 90% since AV does not have a timer but another LEAF showed up so I decided to unplug so they could charge (they only had 24 kwh pack).  At 90%, the charge rate should drop below 20 KW.  (See below) Previously my other multi QC days did not get me over 115ยบ even when doing 2 30 min QCs within a few mins of each other.  This time, I smashed thru that number! 


Temp rolled to 123.1 about 2 seconds after I took this...SomeMurphy" thing I think... 

Now, it was on to home. I mulled the idea of going to Tacoma but realized the 30 min time limit of EVGO would not allow me to see the curve I wanted to see. 

And finally, HOME!!




Back at home we know understand why the car was on for all of the charging. Because now we have a true sense of the time it would "really" take while driving on a 300 mile trip.  If we take out the 94 mins of charging, we averaged about 51 mph which is not really that bad. I have taken several trips in the Prius on longer distance trips and averaged the same so in the absence of pee bottles and recklessness, My trip was in all matter, "normal" for an EV.... 

Conclusions

Well first off, can't make conclusions because we need to do a Summer trip!  Its my hope that the AVE compatibility issue will be resolved so we can do a 700 mile two day trip down the Oregon Coast and across to Roseville to the Safari and then home up I-5.   Its my guess, it will be a VERY long first day...



But this test created almost as many questions as it answered.  We now know that starting temperature is the key factor in the starting charge rates but rising temperatures do not play a part.  Below is a chart of a charge (actually there is a few here) starting with "cool" pack temps low 90's at 75% SOC. Here you see several slopes at 78% SOC gradually dropping to 90% SOC where the slope gets steeper while charging at roughly 22 KW.  Notice the pack temps just getting to the major slow down stage at just over 100ยบ?  But this graph is more dependent on the battery temps and not SOC so again, its taking the most beneficial of the two ramp down slopes (although BOTH suck...) as shown by the short but steep ramp down at the beginning of the charge. 

The big test now becomes monopolizing a station for over an hour to charge from a low SOC below 20% to 90% starting with a pack cool enough to get the full amperage from the charger.  Here we need to record the differences in the knee from 120-125 amp chargers and 100 amp chargers as I suspect there will be no difference.  This leads to the conclusion that the ramp down is determined by percentage of the maximum amperage available and not necessarily the starting amperage. 


Now what does this mean for travelers?  Knowing the maximum charging speed would be key.  Also using a station that doesn't automatically cut off at 30 mins would be another.  You would be better off to charge to a higher SOC since you are likely to charge as much as 5 KW faster than if you were to move farther down the road to another charger.  Even with the lower SOC, if your pack is hot enough, it won't matter. You will be doing 20-22 KW if your pack is above the 115ยบ range. 


So what is the sweet spot?  Well, low SOC and room temperature!  But the reality is what did the slow charging cost me as far as time? Well, in this case, not a lot.  The length of the trip would have required several stops and the reality quickly hit me that the longer range was outdistancing my bladder so each stop was VERY welcomed!  In truth, I also stopped two other times without charging.  But if looking just at real time.  I did this trip in my S30 and it required more but shorter charging stops mostly because I didn't stop at rest stops on the freeway to pee. I stopped where I could plug in and pee.  So it didn't really save me any time when charging faster. But there is an obvious advantage to being able to charge full speed at low SOC no matter how hot the battery as my S30 did. Check my blog from last March. I charged full speed in Centralia at 125 amps with batt temps over 125ยบ.  So Nissan has simply got it wrong. Their concern is high battery temps while my concern is high SOC AT ANY TEMPERATURE.  So we have a double whammy; slower fast charging and a one option 100% overnight charge...