Thursday, July 25, 2019

Decoding Rapidgate And Why Everyone Should Get The Update

Last week I announced that my LEAF tech advised me that a fix for Rapidgate was available. Now this happened last Friday on the 19th for an update that was apparently first available on the 18th.  So naturally, no one had heard about it. This created quite the lively discussion including some feeling that not everyone needed the update.  Well, that couldn't be farther from the truth and I quickly realized that many people don't really understand what Rapidgate is or how it affects your driving experience.

So, I decided to dig out a few blogs on some of the road trips I did last Summer to compare with a drive I took today to see if my LEAF had changed at all.  The purpose being to show just how much additional time is added when the full force of Rapidgate is against you.

As always, if you don't like my banter, you can should be able to figure out the gist of the blog by simply looking at the pictures!


The Test

To level the playing field, I decided all my charging would be done at the same station so I chose the Webasto DCFC in Tumwater, WA.  As mentioned before, when I am not planning anything out of town, I like to keep my SOC between 25 to 70%.  Today, it was a bit higher than the norm considering I did not do my daily 90 minute charge this morning.

Terminology

Knee; This is the point when the current starts dropping.

KW Rating; We all tend to quantify stations based on KW but in reality they should be based on current. In this situation we will use a 125 amp station (which varies from 118 - 125 amps from location to location) which is based on a 400 volt battery pack so that is how we get the 50 KW or 50,000 watts. (125 amps * 400 volts)

After all; which is more accurate?

I plug in at 20% SOC, start charging at 125 amps but only 44 KW so am I getting  100% power from the machine based on 125 amps received of a possible 125 amps or am I only getting 88% of the power available based on 44 KW from a possible 50 KW?

Temperature Gauge; This is the Nissan instrumentation which was a 12 bar graph. Now, its a sideways thing but the basics are the same. Still has 12 segments or pips, etc.  Segments 1 and 2 are blue. Segments 11 and 12 are red and the rest is "normal"

I think I threw up in my mouth typing that last part...

Charge # 1



First charge of the day. Batt temps in upper 70's
charging speed 46 KW @ 124 amps

First charge; 14 mins, 10.37 kwh.  I didn't want to charge too much and Rapidgate is all about the speed of the charge at the beginning. 

Charging Knee 60.61%, batt temps 91, 92, 88.8º F 

So first charge runs at max current which in this case, peaked at 124.37 amps per LEAF Spy logs which is the norm for this station. peak charge rate 47.3 kwh. This is the best I can get from the LEAF.  So all is good but remember the battery started out in the upper 70's. 

Charge # 2

As the day progressed, the temperature rose quickly. Soon it was 86º and very Sunny.  A/C was a must. After a quick sprint to Chehalis to check out the seemingly abandoned EA site, I had lunch and headed back to Tumwater. 

2nd charge; batt temps mid 90's, Charging speed 35.5 KW@ 100 amps

Ok, so we have LEAF Spy so we already know the speed won't be what we are expecting. But others will expect nothing as the temperature gauge will be at 6 pips, ticks, bars (or whatever) which is dead center on the scale. 

Charging knee 68.38% Batt temps; 112.2, 110.4, 106.7ºF

Notice the knee has moved to the right? At the knee, charge rate was 34 KW.  On first charge, SOC was 67.44% @ 34 KW.  So loss is not too bad, yet...

12.57 kwh in 21 minutes.  It was my intent to stop the charge at 10ish kwh like the first charge but was talking to a Bolter so was distracted a bit... 


Charge # 3

3rd charge; 24 KW @ 68 amps. 

So now we start seeing some real effects. As you can see in the upper left corner, my charging speed is nearly cut in half.  I am at 8 temperature segments (2 segments past center) 

Charging knee; not obtained. At this pace, I would be over 80% before that happened.  
Batt temps 118.7, 118.7, 112ºF

Charge summary; 10.42 kwh in 26 minutes. In a normal situation, I would have likely had to charge another 15-20 minutes or so. That makes 46 minutes charging.  Good for a meal but not so good if its just a pit stop. 

8 Temperature segments

Now, mind you, it gets worse. MUCH worse. Last Summer, at 9 Temperature segments (notice still not in the red!!) 

 On a 30 minute DCFC session, I went from 27% to 48% SOC. I didn't even get to half full!

Now, this was the 2nd Ellensburg trip which was quite the distance eventually running over 250 miles but today how far did I have to go to see almost a 50% reduction in charging time? 


Yep, that's right. 116.7 miles is all I had to drive to get to a severe Rapidate condition.  Ok, I admit I drove a "bit" fast but as you can see with 4.5 miles per kwh, it couldn't have been too fast. You can ignore the average speed as the car was on for all charging sessions plus a 20 min conversation with the neighbor as I was leaving the house today.  I did use A/C but set to 80º with fan speed on 3. Was very comfortable although I did not have it on during charging as it would have affected the numbers. 

Get The Update!!

Even if you don't ever plan to quick charge more than once a day, everyone should get this. My tech  did bring up an important point that the update NTB19-056 is free for in warranty vehicles and most if not all 2018's and 19's should be in warranty. This means if you don't get it now and decide to sell your LEAF down the road, you will either be screwing over the new owners or simply losing value on the resale if the prospective buyer is wise enough to catch the fact the car was not updated. So do it while its free. Hold Nissan accountable for their actions! 

Now some have had difficulties requesting the update simply because service advisors are just as much in the dark as we were before I and others started publishing info about the existence of the update.  Below is all the info you will need to give to the service advisor. 

EL19-018 and reference NTB19-056. It’s titled “2018-2019 LEAF; LITHIUM-ION BATTERY WILL NOT QUICK CHARGE.” 


Note

Its too early to know what Nissan's stance is on this.  This update will cause your pack to be hotter than was possible without the update.  So learning to charge judiciously is needed to ensure a long battery life. 

To illustrate; on the last charging curve graph, I basically started and ended my 30 min charge at 16 KW. Notice the black line? That is the battery temperature line.  My battery temp went from 122º to 125º so hardly a budge at all.  My 2016 surpassed 130º at least a dozen times. 

But this update will allow the pack to soar into the 130's; a place that was all but unreachable without the update with the obvious exception of places like Phoenix, etc.  Now, those situations will be rare and will require a lot of things to line up like terrain, weather, speed, etc. 

But you control most of that. Getting the update installed whether you need it or not is holding Nissan accountable but you have to hold up your end as well.


6 comments:

  1. How hot is too hot for battery durability in newer Leafs? IIRC, your older posts equated increased temperature, & charge >80% with more rapid battery degradation. The color scheme for Leaf Spy Pro temperature shows >105 as being red.
    I purchased my `19 Leaf+ because it meets my needs very well, so intend to keep it for a long time. I've been using the charge timer to keep the charge 15-85% with charging after midnight to minimize heating & to use the grid at low-demand time. Ron

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    1. By red if you mean the 11th temperature bar, that is over 130º. 105º is only 7 TBs (one past the center)

      Now we have to realize that heat is a catalyst to degradation. So the "danger" zone is based more on SOC. High SOC degrades at any temperature. This is basically true for all Lithium batteries but Nissan selected a chemistry that is more prone to this especially when temps hit 140º. But 140º is not a turn on point. Degradation happens at room temperature if the pack is fully charged.

      So the only thing you should be worrying about is not overcharging. Putting in more charge than you need. What I do is charge a little every day because my commute is so short. I admit I will QC every once in a while during the work week if its convenient and that will last me 3 days but I never charge over 70% in Summer, 80% in Winter.

      Now, lets not put too much into those numbers. This is my parameters based on expected driving, etc. Yours is likely different. You have the Plus so you can likely live in the middle with SOC running between 25 to 70%. That is what you should do and then give it a full charge just before heading on a weekend getaway.

      In your scenario, I am guessing you charge daily so 70% of a 220 mile range is a lot of driving. Keep me posted on how your pack is doing!

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  2. By Red, I was referring to the default color scheme on Leaf spy (e.g. https://images-eu.ssl-images-amazon.com/images/I/71dc703O3NL.png)
    I don't charge daily. Typically Tues, Fri & Sat.. M,T,Th,F my commute is 35 miles round trip. Sat is 100 miles each way. Fri night I charge to about 60%, arriving at work with 15-25 miles range left. It charges at work (free L2), sometimes hitting high 90s%, and I get home with 150 miles showing (work is 2000 ft higher elevation than home), Charge it Tues or Weds to 70%, and then it's Fri. My wife's Volt gets the charger the other nights.

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    1. Sharing a home charger is a challenge especially with TOU. I think you will be fine although I think I would do a bit less charging at work. Maybe plug in at lunch time or something to lower SOC? 90% is pushing it if you are in a warm climate and parking is uncovered.

      I think this is source of a lot of degradation. People taking advantage of free charging at work without realizing the hit on the pack.

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  3. Thanks very much for the advice, I will use the timer to delay starting. I have learned a lot from your informative blog. Thanks

    ReplyDelete