Friday, June 19, 2020

Evaluating Range Needs In A Nissan LEAF

Previously, the car buying decision was all about deciding if the bling A you wanted was worth paying for package Z containing bling A.  After that, it was pick the color, negotiate a price and go.  Well, things have changed since EVs hit the street.  Not only is there the dilemma of several different charging protocols, there is also pack sizes. Nissan has joined Tesla in offering more than one pack size and soon this will be the norm in the industry so what is important to know?

In The Beginning

Back in 2010 when we were all anxiously awaiting the LEAF (the only real option back then) to arrive, we all evaluated our range needs based on two things; Nissan's claim of a 100 mile range and the EPA claim of 80 something miles (later changed to 73 miles due to the 80% charge setting according to them anyway...)

But that was not real world and despite Nissan issuing a chart detailing several driving scenarios and ranges expected, most people ignored the chart or simply didn't know it existed.  There is not one single report of a chart sighting at any dealership in the US... not one.

But if customers had seen the chart, they would have realized that their 100 mile EV could do no better than 47 miles under certain conditions. I would post the chart but even the chart gets it wrong... Ah! I will post the chart anyway since many do not believe it ever existed.



Now that we see the chart, experienced LEAFers will immediately point out that the bottom two ranges are flip flopped.  A/C uses nowhere near as much power as the heat. 47 miles in Winter especially with snow on the ground could make even 47 miles a challenge and you didn't have to drive 4 hours to find out!


Driving Blind

January 18, 2011 I made the journey about 50 miles to pick up my 2011 SL with charge. I expected to hit the dealership just before noon with my 3 year old Son in tow so expected to be home by late afternoon.  That did not happen.  This was one of the first LEAF deliveries in the state and my dealer had no clue what was going on.  I had intended to purchase the car but while fighting with the dealership over sales tax (of which there was none) I had an epiphany and realized that spending over $28,000 (after credits, etc) for V 1.0 was a mistake.

So I flipped to a lease. This created another delay.  So after spending over 3 hours trying to figure out how to create a lease that did not include sales tax, they finally decided to call corporate who spent about 5 minutes providing them a workaround.  To make a long story short, I left the dealership around 7 PM.  (I had to return a few days later to sign another lease form anyway)

Anyway, I am now driving home in the dark of a January night with heat enough to keep my son from freezing (later I realized he is MUCH more cold tolerant than I am) and my range display starts blinking and the dash lights up with all these dire warnings and I am still more than 10 miles from home.  I was unceremoniously introduced to the World of range anxiety!

Scotch Tape Is Your Friend

Later, I realized that all my panic was for naught. It was a brand new car with nearly 22 kwh of energy of which I could easily use over 20 kwh to get me anywhere. Even in winter (which ours is relatively mild and nowhere near as bad as the scenario in the chart above) I had more than enough range.  Soon new acronyms flooded the LEAF online community; LBW, VLB, GOM, POS... (JK on last one!)

Jan 26, 2012; A few weeks before GIDmeter. Notice only 3 power circles remain?  Proof 100 miles in Winter was possible (No, it was far far far from easy!) 

By now, it was obvious that 100 miles on a charge required a lot of things to go right which means the real question is how far can the average person go? Who was willing to have a tow truck follow them to find out?  Realize this was waaaaay before public charging was commonplace.  In my city, we had Lacey City Halls level 1 plugs that had been there for years and the summer before, the water treatment plant had a level 2 installed and due to proactive NEVer, we had a half dozen businesses around town offering wall plugs for the needy to plug into but that was about it.  Realize how little we had BUT it was much much more than nearly everywhere else in country who had NOTHING.

But the LEAF was cutting edge tech which naturally drew a lot of techies. Soon DIY projects started popping up. The main goal was digging up what Nissan was hiding under the LEAF dash.  Soon, the "Gidmeter" was available in a kit you could build.  It's various displays showed voltage, current but the most important thing; it revealed the actual capacity of the  pack in GID's.

Now, we don't really know what a GID actually is other than it counts down as the power is taken from the pack and it counts up when power is added to the pack.  Thru some reverse math, observations, etc. It was initially determined a GID was about 80 watt hours of stored power.


Later, a value of 77.5 watt hours of power was settled on. the 2011-12's had 281 GID at full power while my 2013 had 284 GID and several 2015'ers reported 292 GID (if you ever needed proof Nissan WAS working the battery issue ALL the time, this is it)

Now we knew how much the LEAF had when full and that was nice and all but not really what we needed.  It was all about avoiding walking, pushing, or sitting in the front seat of a tow truck. The real question was how low can we go!  (Thank you Limbo dancers for that phrase!)  but the GIDmeter allowed us to report to each other what we were able to obtain. Some got to 4, some to 6 before Turtle arrived (the point when LEAF restricts current draw from battery).  This allowed us to know within a few 10th of a mile how much range we had.

Armed with GIDmeter, the "100 mile" challenge quickly lost its appeal. It simply wasn't that hard any more.

Despite being a few miles from 100 with plenty to spare, it was no longer worth 
circling the neighborhood like the "pre GIDmeter" days.  

But despite a ton of pictorial evidence, people still freaked out over the GOM to which we advised; If you want a LEAF with longer range, tape over the GOM and get GIDmeter!

Degradation

Soon the "good old days" (which kinda sucked actually) evolved to the life of plenty. We now have a bunch of charging options.

AV Tumwater May 2012

Packs grew and soon the challenge was 300 miles but there was still a case of packs degrading. Some went downhill fast, some lasted a long time.  This caused a HUGE amount of misinformation on social media including many who thought that Nissan had "fixed" something so the reason they removed the 80% charge setting was because it was now ok to charge to 100% all the time.  This couldn't be farther from the truth. There are major physical challenges Lithium based packs face and NO AMOUNT OF TMS, BMS will fix it and that is higher rates of degradation at high voltages.  EVERY EV manufacturer knows this and EVERY EV manufacturer who has TMS also has custom charge settings to help the user preserve their packs. 

To add to the confusion; LEAF battery reports which only evaluates the driver NOT the battery pack had people claiming they still had 100% SOH because they earned 5 stars.  Others who admittedly never challenged the range of their LEAFs claiming no degradation while charging to 100% unnecessarily because they still had 12 capacity bars. 

For some reason; many LEAFers thought the #1 reason for degradation was lack of TMS and that is simply NOT TRUE.  It definitely doesn't help and heat is a problem but not the main problem.  Degradation is a combination of a lot of things;

Climate
driving style
driving need
charging habits
DoD (depth of discharge)
Time

Add in TMS and the list is 

driving style
driving need
charging habits
DoD
Time 

A Tale of Two LEAFers

The Pacific Northwest, particularly the Puget Sound region of Western Washington has long been known as a sort of "EV Nirvana" Our near idyllic weather which is not too cold, not too hot, has mitigated a lot of the climate issues which minimizes the benefits of TMS here.  This is illustrated quite well with Steve "the quarter million mile LEAFer" and John.   Both live in the area and have long commutes but there are huge differences in their LEAF experience. 

Steve

Steve had two LEAFs; a 2011 and 2014. Both basically fared the same. Both lost their first bars at just over 70,000 miles.  Steve's commute was about 67 miles one way. He charge to full on level 2 every night and plugged in immediately to level 2 charger upon arriving to work in the morning usually being fully charged by early afternoon.  His commute was nearly all freeway and he drove conservatively usually around 65 mph.  By 100,000 miles both his LEAFs were all but done.  DC charging did help him get more use out of his LEAFs but he was all but forced to get something different and at the time 30 kwh was not enough. 

John

John has a 2015 LEAF. His commute was a bit shorter at 50 miles. He charged to full every night on level 2 then stopped at a DC charger near his work and charged up to around 80-90% give or take for the drive home.  Unlike Steve, the bulk of his commute was on state highways with speed limits of 55 mph that passed thru several small towns with speed limits dropping to as low as 20 mph.  Although his drive seems inconvenient, it avoided the mess on I-5 so really only took a bit more time and was quite a bit less stressful of a drive.   At 100,000 miles his LEAF was LESS THAN halfway to losing its first bar. 

12 bars @ 150,000 miles 

DoD

Now everyone with a 2015 will confirm the "Lizard" pack improvements were nowhere near enough to explain the disparity.  So why were these two experiences so different? Climate (and TMS) wouldn't have changed anything.  A deeper look suggests that DoD was a key factor.  With an estimated 73 miles of range, Steve's commute used 84% DoD (based on 80 mile range) while John's commute used 63% or less. The 2015 pack had more power available but probably less than a kwh over Steve's 2014.  Steve charged to 100% twice a day while John only charged to 100% once per day.

Even if they had it, 80% charging would not have covered their needs very well.  It should be noted that the difference in driving conditions and styles probably plays a part. John likely used regen a lot more due to more speed changes required on his route and he prided himself on gentle driving with very modest acceleration and maintaining constant velocity as much as possible. This would have lowered his DoD needs as well.  But Steve's real claim to fame (IMHO) was his ability to get over 80,000 miles from his OEM Ecopia's. Yes, he was the first LEAFer to go over 100,000 miles in a LEAF in the US but to my knowledge; his tire longevity record still stands alone with no one even close.  This means his driving style was unlikely to be radical.  

Charging (Again!)

I could realistically access a dozen past blogs and simply cut and paste this entire section. I have repeated this information over and over and over.  Sadly, Nissan is now the ONLY major EV manufacturer without custom charge settings and it is literally KILLING their reputation.  Lithium packs have the same needs and desires as people.  They don't like living on the edge. They sweat in the heat, shiver in the cold. They simply want to live a comfortable stress free life just like us. So what does all that mean?

Lithium prefers life in the middle; 50% SOC as much as possible.  (actually its closer to 45% for long term storage) This is the ONLY thing you need to keep in mind when charging the car.

Back in the "good old days" we charged the car daily because it simply didn't have "2 day range." Nowadays, my car has 5 day range and TBH, that includes a MONSTEROUS buffer.  So my charging habits have morphed from a top 5 priority to...well nothing really.  I don't even think about it any more and its hurting my pack.

My mind is literally still in "24 kwh" mode.  I used to get home from work nearly every day with less than 10 GID in the tank and that was accomplished by carefully monitoring my speed, distance, and power usage. My 2013 and 2016 had an SOC meter on the dash and I venture to say the total number of times I referenced that information on BOTH cars was well less than half a dozen times. It was all about understanding how the GOM worked and how much farther I had to go.

Today in my E Plus, I glance at the GOM, see 60 miles knowing I am only going 20 and poof! No longer care about speed, power usage or charging... HUGE MISTAKE!!

Charge Every Day!

Battery U has done a lot of testing on Lithium and it is or should be well known that many many shallow DoD charges are better for long term battery life than a few big DoD charges.

In one test, they determined cycles to degrade a pack to 70% of its original capacity.  In the 80% test (90 to 10% SOC) which many think is a good thing because its not charging to full; it took ~300 cycles to degrade the pack.  Multiplying; we can assign a "range value" of 24,000 which is simply 80% capacity added * 300 charges.

60% DoD took about 600 cycles with a range value of 36,000 (remember the two LEAFers above?)

40% DoD took 1,000 cycles or a range value of 40,000.

My current daily commute is about 24.5 miles more or less (depending on where I park at work) and my E Plus has a range of 250 miles at this time of year so I use about 10% DoD daily.  At 10% DoD, my range value is 60,000.

So why charge every day?  As mentioned, the battery wants to be around 50% SOC. Be it 45 to 55% like me or 20 to 80% like John.  Even in more extreme cases like John, the predominance of time spent is around the midrange SOC level.  Another reason why its important is heat. Yes, I said its not the main cause of degradation because its not but it's still a factor and I mention it now because too many people have the wrong idea about what heat means.  Even at very moderate temperatures commonly seen in the Pacific Northwest, the relationship between SOC, temperature AND time is critical.  Below a chart and realize this chart should only be used for relational information only. Chemistries have improved which help but the phenomena is a simple fact of physics and chemistry. Heat is a catalyst, not a cause.


Without TMS, this is the least controllable factor of degradation; temperature. This chart should make it plainly obvious what our options are.  Looking at the 25º C line (that is 77º F) , its a 500% increase in degradation if charged to 100%.  In my world, 77º is a nice warm day. Nowhere near hot. Raise the temperature, raise the degradation.  Granted we are talking a year which is a good thing in that charging to 100% when you need it even if you need it a lot isn't going to hurt "a lot" but it will hurt, make no mistake on that.  But its also a bad thing because the "hit" is so small. We lose the ability to understand how detrimental our day to day actions are especially when we are doing this needlessly which brings me to something that all of you have heard me say.

Charge ONLY to the level you need to cover today's driving needs. 

You and you alone are the only one who can determine what that level will be because it not only has to cover your expected daily needs but also a buffer that will cover your likely unexpected needs. Now we are all by and large creatures of habit especially during the work week. My schedule varies so little on days I work its...well boring.   I have a half dozen places I may stop at on the way home but they are literally on the way so I might add 10 miles to the commute but most of the times I am adding less than 2 miles. 

Now on my days off, its wide open. Road trips, family stuff, etc. It covers a very wide range of driving needs but all that is planned in advance so no real surprises and yeah 62 kwh helps a TON with that. It is nice to charge to 50% and have enough to cover my needs plus a 100 mile buffer!

My Recommendation

If you have done your charging needs evaluation and you feel  you have to charge to 100% then you are driving the wrong car.  FYI; the "90% to 10%" idea is BS. Anyone using more than 70% of their range should be charging to full but that is a LOT of need and few of us are there unless we are in the used EV market.

So if you want an EV that will last you 10 years, get one that covers your needs with a 40% DoD

Friday, June 12, 2020

E Plus Summer Range Test

Now that most of the region was in phase 2, it was time for a range test. I could have just figured out a loop of the right length but there was no way my ass would survive nearly 4 hours in a car in one shot so decided that a goal was better so the plan was lunch in Portland and back to my home in Olympia. Round trip distance; 242 miles.  There is of course the Olympic Peninsula route but a pending EA site in Port Angeles means I might just have to wait for that site to open first. The other thing was I had already promised myself my next peninsula trip  would be with my Son camping... somewhere.

The Plan

The route will be 90% freeway. I decided a Thursday would be best for minimal traffic. Heading down in mid morning, spending enough time in town and heading back mid afternoon, I would miss any rush hour traffic. Only real requirement. The destination has to be less than 3 miles off the freeway.

I used cruise control set to 65 mph and only needed to bump the speed in 1 mph increments up and down to account for traffic.  

SOC; GOM Verses LEAF Spy

It should be well known that the dash info is not a good tool to use for a range test.  Recently someone did a range test in the Plus stopping at 1% SOC (maybe it was 2%)  to charge figuring that they had really "risked it for science" by going that far. It took me several minutes to recover from my uncontrollable bout of laughter which is why when anyone asks the best method to extend the range of the LEAF, my answer is "Get LEAF Spy."

LEAF Spy allows you to set your own miles/kwh target.   So simply decide where you need to go, how far it is and then use LEAF Spy to find your target miles/kwh figure.  What I do is simply take off aiming for .1 mile/kwh over my target to see if I can reasonably hit it. This doesn't always work due to wind, weather terrain, etc.  but if its a goal that seems unreasonable, I start planning alternate charging options while still over 80% SOC and 200 miles to play with.  This trip being short enough, I won't have to worry about that. 

GOM (guessometer) is well named and the reasons are obvious. Despite both being labeled "SOC"  they don't even run on the same scale.   The GOM runs 100% to Zero or "_ _ _" .   LEAF Spy runs from about 98% to 1.5% and both LEAF Spy numbers are dependent on cell balance.  The highest charge I have ever gotten was 99.3% but typical is the mid 97's to the low 98's. The lowest 1.4% so the usable range of LEAF Spy's SOC meter is essentially about 97% of the available capacity.   Now we know that LEAF Spy shows "real" SOC and if the GOM showed "usable" SOC, I would be OK with that, but it doesn't.

So what I did is record the LEAF Spy SOC every time the GOM SOC ticked downwards.  I was able to capture each reading as the GOM updated except for 7 but at no time did I miss more than one reading (IOW, I caught 77%, missed 76% and caught 75%) I used the dictation program on my phone so it was simply a question of logging the data into a spreadsheet after I got home.

Now LEAF Spy only shows SOC in .1% increments but does not actually calculate it that way and there were a few times when LEAF Spy incremented a split second after the GOM so I took the lower reading in those cases.  This means a .1% variance is possible.


Points to Ponder

** In ECO mode, I had an estimate of 251 miles but in D mode, the estimate was 235 or just a touch over EPA.  LEAF Spy estimate was 252.2 miles at 4.5 miles/kwh to 1% SOC (my average over past 3 days before test was 4.4 miles/kwh)  Both the miles/kwh and SOC target are selectable. So choose your comfort level. 

** At 88.0% SOC, Both the GOM and LEAF Spy AGREE!!

** At 59% SOC GOM/ 63.0% LEAF Spy, the range estimate agrees (LEAF Spy set to 4.3 miles/kwh to match GOM)

**The largest gap happened at 22 and 21% when the gap was 10.7%.  This a radical change from previous versions of the LEAF which includes the 40 kwh LEAF where the reserve continues to grow all the way to zero which means...


** The data   Click the link if you want the specifics. 

LEAF BMS/LBC

There are many scientific reasons why we should not charge beyond our needs. We all know full charges increase the rate of degradation but the ideology that 80% is a golden number is also wrong. You want to stay around 50% SOC as much as possible for longest life.  But I recently came across a LEAF Spy screenshot that I was convinced was altered or "something"


Notice something here? Ok forget the ultra tight cell balance, the HUGE degradation, etc.   Look at the lower left corner; 100% SOC??? WTF!!!   This explains the degradation issues.

**EDIT** Now that I have over 2 years on the Plus, I have hit 100% and 99.9% SOC  twice  despite only having 15 lifetime full charges. More evidence the Gen two BMS isn't telling everything! 

Has anyone ever seen anything like this? I was shocked when my 40 kwh pack charged to 99.3% It only did it once and 2nd highest was 98.54% The rest were in the 97% range. In an effort to see how high I could go I bumped my charge twice (unplug when charge is complete and plug in to restart) and got no more than 98.3% (poor top end balancing I guess?  This was only the 2nd time at 100% per dash. The first time was when I picked it up from the dealer)

But this "playing with fire" should be enough to make anyone nervous.  Just another reason why charging to full on a regular basis is a bad idea and should only be done when the need is that great and immediately after the charge is completed.  The reality is BMS/LBC programming is apparently still work in progress!

The Charge

On my Winter Range test of sorts,  the end balancing of the pack too much longer than expected so I unplugged at 98% SOC. The car was only pulse charging between 4 to 7 amps so wasn't missing a whole lot.  Well, the same thing happened here.  I get roughly 10% per hour of charge and the timer was set to start at 4 AM and add about 36% of charge.  At 8:30, I checked it expecting to be finished and it was still charging this time around 8 amps.  Ok, this was familiar.

Notice the OAT of 73º? Garage was nowhere near that warm. Looks like thermometer is too close
to the inverter which does get warm during AC (doesn't heat up during DC charging) charging. 

98% implies that there is still nearly 1.5 kwh to add. My meter which only shows one kwh increments did not change but its maximum  error could be 1.5 kwh so we will consider that if deciding to upgrade the meter some day.  BUT....

Hitting The Road!




So after completing the charge AND bumping it twice, I am now at 100% SOC per the GOM and my range... has gone down. I guess cell balancing is not very efficient!  Yeah well, its the GOM, right!


So everything was set...except for the weather. It was raining. The weather stated 40% chance of rain so it was kind of a coin flip.  Taking off, I decided to aim for downtown Vancouver instead which was a 15 mile shorter drive round trip.  The wet roads lasted until around Castle Rock, then we flipped to partially cloudy skies and by the time I got to Vancouver, the A/C was on.


Arrival Vancouver

I was beginning to think my alternate route was a mistake since the weather was now quite gorgeous but then again 

FREE parking downtown Vancouver until June 30th!

So Vancouver was turning out to be as good a decision as the weather! Using Yelp, I found a parking space that had at least a half dozen highly rated eateries within a few blocks.  I was literally 2 blocks down the street when I saw this


Outside dining on the covered porch was simply too good to pass up! But I elected to do the A/C inside and that turned out to be the right decision as it got very warm in the direct sun and after a large bowl of pho noodles, I was more than warmed up! 

Another reason I selected Vancouver was due to a city park surrounding Lake Vancouver near by.  They had a lot of walking trails so after lunch I headed over there. 

Obviously someone with COVID 19 had been swimming here! 😏

After a few miles of walking off the food (Got a sandwich as well!) It was time to head back. My plan was to get back to town before the afternoon rush started.  The drive home was uneventful and warm. A/C was on most of the trip. My A/C does not respond to the thermostat which means despite it being set to 84º, it gets a bit too cold sometimes.  So I toggle the compressor on and off. I guess its better than not cold enough. 

LBW came on at 14.6% SOC per LEAF Spy and soon after that, I hit EPA!


I got back to town a few miles later but couldn't stop since my SOC data was not complete so I wandered around town a bit, did make a few quick stops and finally

Zero % SOC on GOM achieved at 237.4 miles. Yeah, was slow taking picture due to voice control issues? The picture phone is mounted on a holder and I simply instruct Google to take a pix. For some reason, Google decided to ignore the first few requests?  Increment from 1% to zero was 1.8% SOC on LEAF Spy! 

Why LEAF Spy Adds Range You Didn't Know You Had

So for all intensive purposes and for any writer reviewing the LEAF, the car has given its all, right?  The GOM range has been all dashes since 230 miles, the SOC  has been all dashes since 237.4 miles so we are done, right? On the verge of entering the "Towing Hall of Shame" right? 

Yeah well, we shall see. I decided to swing by the West Oly EA site to see if the cut cables had been replaced so that was a quick jaunt on the freeway there and back and then to the store and then home. Remember the 251 mile estimate on the GOM this morning?  Well, I have been bashing the GOM all day and well, lets face it; The job was not complete until... 

GOM exceeded and LEAF Spy says I still have enough for a MiSo run! 

NOTE; I briefly thought about driving around until I hit the well known 24 GID but I thought that would be rubbing it in a bit too much. 

Saturday, June 6, 2020

April/May 2020 Drive Report

It appears no one missed last month's report so I felt a reminder that you should be anxiously awaiting each month's report was appropriate. 😊

Since this report is covering 2 months, a report on the battery's 90 day adjustment is next and yes it happened pretty much right on schedule.  If you recall, the first adjustment was the largest ever  (2 cars!) so being a bit apprehensive was a bit of a concern despite multiple reports of  milder adjustments coming from all over the World.  This one started April 25 (the first one started January 25th and lasted 9 days) and ran 4 days.  I lost 1.29% SOH this time so hardly a good thing but at least it wasn't an extreme thing like the first one when I lost over 2½%.  Probably not a factor but in 2 of the 4 days, I DC'd and drove over 90 miles.

Either way, my current stats has me at ahr 167.90, SOH 95.18% with just over 8800 miles.  My mileage totals would have been much lower but had a unique opportunity to be part of a labor shift at work in order to address rapidly escalating needs caused by COVID 19.  This meant my normal 25 mile round trip commute went to 47 to 50 miles one way.  Yes, I was paid a bit more to do this but the real incentive was being paid 57 cents per mile from my home. 

I had only intended to do this for a few weeks just to see what it was like but after getting my first two reimbursement deposits, I quickly decided I was riding this cash cow into the ground! I mention this as justification for my driving over 3000 miles during the height of the stay at home phase.  I ended up doing 6 weeks at 4 days a week banking over $1300 in travel reimbursements.  All my charging during the first 3 weeks used my EVgo promo received when I picked up my E Plus.  EVgo sweetened the pot by dropping its lowest per minute rates 25% and removing the subscription requirement due to COVID.  This COVID  pricing was recently extended to June 30th.  I suspect that will be extended again.  The last 3 weeks, I only used EVgo on the last day of the work week, charging at home for the rest of the week. This was mostly done to gather info on best charge timer settings.

For the month of April, I drove 1668.2 miles averaging 3.93 miles/kwh using 400.54 kwh from EVgo and 6 kwh from home costing me an all time high for the Plus of $5.57 (8.44 cents/kwh)  In May I traveled 1354.2 miles averaging 4.11 miles/kwh using 118.57 kwh from EVgo and 236 kwh from home costing me $20.41.  (Guess that record didn't last long)

Neither month saw me using public AC charging. My main use is at Capital Mall in West Olympia when seeing a movie. Looks like that won't be happening any time soon... Hopefully Cinemark does not go under before then. Their movie club is a bargain.

Managing SOC

As mentioned, my long commutes enabled me to play with charge timers and I found the easiest way to control SOC was to set the timer so the car is still actively charging when you get up or are planning to leave.  Since I was normally up 90 minutes to 3 hours before my scheduled departure for work, I had that much leeway as far as how long I wanted to charge.  This meant not having to adjust my settings every day.  But even if adjustments were necessary, it quickly became a 10 second task after learning the navigation settings to the correct place.

Now I am still using the EVSE I got for my 2013 LEAF which did have a 6.6 KW AC charger but my panel was not up to the task. Living in an old house, my panel is a Zinsco which has since been banned for new construction or upgrades. This means getting breakers for the panel is all but out of the question.  Luckily, I  had an unused 30 amp breaker than had been used for a pump on the old septic system so I am restricted to 24 amp charging which is fine by me.  I have never been inconvenienced by this but then again, if you have followed this blog you would know I have done minimal home charging over the past 3½ years.

Well, that gravy train is all but gone. I have only a few bucks left on the EVgo promo, my NCTC expired in February so I am on my own. Either way, it took all of a few days to see that I charge about 10% per hour.  I say "about" because the LEAF SOC meter is not linear.

Now what makes sense is the meter on showing usable capacity and that would be great...but it doesn't. It has a hidden reserve that slowly grows as the SOC drops. When the SOC meter hits zero you have about 20 miles of range on the Plus so keep that in mind before you complain you didn't hit the EPA numbers.

With the Plus, the error is a non issue. Whether I charge to 60% or 65% is not important to me.  Its more than double (in some cases quadruple) the range I expect to need that day and its in the "good for battery" zone so all is good.

Decoding the Algorithm

Another thing I wanted to look into is why these 90 day adjustments are happening.  The 2018's all seemed to follow the exact same pattern. Numbers never rose. They either went down very slowly or stayed the same then after 90 days they would drop a chunk.  This went on for nearly everyone for 12 to 18 months then nearly everyone saw an adjustment that went up. There was also adjustments that stayed the same or simply were too small to notice (not everyone checks the LEAF Spy daily like I do)

Then the Plus came along and the 90 day adjustments are still there but this time there is a twist. Most are seeing small adjustments between ¾ to 1¼% but then we started seeing reports that people on their 2nd or 3rd adjustments saw numbers go up!  Remember the March 2020 Drive report?  I quoted a LEAFer in Phoenix who has gone double the miles I have and has half the degradation. But unlike me who has done 90% DC charging, he mostly does AC charging AND he always charges to full!

Now its one thing to state the obvious that Nissan is making progress towards a cell chemistry that doesn't need active cooling but to do it in Phoenix is way over the top!  Either way, I still do not recommend charging beyond what you need.  So if you need 200+ miles that day, charge to full!  But if you need 50 miles that day, I don't see any good reason to charge over 70-75%.

But maybe there is another reason for these adjustments? Could they be evaluations or predictions of how our pack will go? It isn't really possible for a pack to gain capacity so what other explanation is there for the increases?  What if our habits during one 90 day period were particularly bad so we got a very large drop but then the next 90 day period our habits were very good. Would that cause a change to the algorithm that created that very large drop so extreme that it results in an increase? 

Now I know this is pretty far out there but then again, I am in a unique position in that I am going from nearly all DC charging to nearly all AC charging.  Will this make a difference in my next adjustment? 

Breaking Down the Adjustments

As mentioned my first adjustment started Jan 25 or 2 months and a week after I picked up the car. This implies a build date "around" October 25, 2019 and 10/19 is the build date of record. Unfortunately, there were several other unusual events preceding the start of the adjustment including my 2nd full charge (the first was done by the dealership) for my Olympic Peninsula drive.

First Adjustment

First thing you will notice is nearly all my charging was DC @ 648.489 kwh.  Adding that it was winter this means I was charging the car every 2-4 days so my battery temps were generally low in the upper 40's to 50's most of the time.  Don't know if that matters but just putting it out there. 

Second Adjustment

My 2nd adjustment the high DC usage continues. During this adjustment I drove 3534.7 miles, adding 835.66 kwh of DC recording 875.1 kwh usage from the dash. So pretty much the same charging pattern as before.  This adjustment started during my 3rd week of labor share commuting. 

Currently I am now 50/50 on DC/AC charging since the 2nd adjustment. We shall see at the end of July if it made a difference. The results would be more valid if it was still Winter but I am planning a quarter of near 100% AC charging right after next January's adjustment so stay tuned. 

If you have any questions about the data presented, chime in thru the comments. If you are wondering, there is probably someone else wondering the same thing.