Everything you might want to know about the '18 LEAF engineering

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And you have only one example of a manufacturer with long-lived battery packs, and it just happens to have thermal management.
Click to expand...

And GM, using ? NMC chemistry variant and LG cells
BWW, using Samsung (I think an NMC variant) cells

You might also consider Tesla and BMW technology expertise. You think they spend all that money for TMS R&D and production for naught ?
And the small matter of a veritable mountain of scientific inquiry showing that batteries are sensitive to temperature in myriad ways.
Then there is Nissan, with its non TMS battery that does so poorly in warm climates planning to add TMS to its next gen LEAF. Incidentally, what chemistry is in the 30 kWh LEAFs that are achieving new records in capacity loss ?

Sorry, but you are arguing a no-brainer. Reminds me of people who are not sure whether AGW climate change is real. I understand your *hope* that the battery does better than all the evidence suggests, but that does not change the odds being against you. WAY against you. Honestly, I apologize for for being such a Debbie Downer for you and others who have bought a 2018 LEAF. I'm not writing to spoil your day, but to warn others considering the car of the likely battery risk.
 
SageBrush said:
And you have only one example of a manufacturer with long-lived battery packs, and it just happens to have thermal management.
Click to expand...

And GM, using ? NMC chemistry variant and LG cells
BWW, using Samsung (I think an NMC variant) cells

You might also consider Tesla and BMW technology expertise. You think they spend all that money for TMS R&D and production for naught ?
And the small matter of a veritable mountain of scientific inquiry showing that batteries are sensitive to temperature in myriad ways.
Then there is Nissan, with its non TMS battery that does so poorly in warm climates planning to add TMS to its next gen LEAF. Incidentally, what chemistry is in the 30 kWh LEAFs that are achieving new records in capacity loss ?

Sorry, but you are arguing a no-brainer. Reminds me of people who are not sure whether AGW climate change is real. I understand your *hope* that the battery does better than all the evidence suggests, but that does not change the odds being against you. WAY against you. Honestly, I apologize for for being such a Debbie Downer for you and others who have bought a 2018 LEAF. I'm not writing to spoil your day, but to warn others considering the car of the likely battery risk.
Click to expand...

Well this is unproductive. You either didn't understand what I wrote or didn't bother to read it. Several of your questions and troll concerns were addressed in my last post and previous posts.
 
johnlocke said:
Using the latest battery chemistry (NMC 811) you can get 1250 charge/discharge cycles (2.8 vdc to 4.2 vdc I.E. 100% discharge) at 45 degrees C. before you lose 20% capacity. And that's at 1C charge and discharge rates. Goes up to 1500 cycles for 20 degrees C. For a 60 KWH battery, that works out to 250K miles.
Click to expand...
Can you please provide a link to a reference with this information?
 
Since I am thinking of buying a BMW i3, I looked into the cell details a little.
They are manufactured by Samsung, and I think packaged as 94 Ahr pouches. The label on a cell says 3200 cycles though of course I don't know test variables. Since BMW builds a pack with TMS and liquid cooling, I'm optimistic that these packs are going to last the lifetime of the car. Certainly anecdotal reports have been very good so far -- about 5% loss over ~ 4 years and up to 40k miles.
 
OrientExpress said:
https://pushevs.com/2017/09/08/lg-chem-will-introduce-ncm-811-battery-cells-evs-next-year/
Click to expand...
Thanks, OrientExpress! I've seen that article, but I don't see anything about cycle life there. I'm wondering where that data came from. Do you know?

Also, I will note the following from the article you linked:
PushEVs said:
Theoretically, the energy density of NCM 811 battery cells can reach 1.000 Wh/L,...
Click to expand...
That's very impressive!
 
OrientExpress said:
SK had a press tour briefing last year announcing their new product.
Click to expand...
O.K. Thanks!

So those numbers were from SK. Do we expect similar cycling capabilities from the LG Chem NCM811 product or is it too early to tell?
 
RegGuheert said:
OrientExpress said:
https://pushevs.com/2017/09/08/lg-chem-will-introduce-ncm-811-battery-cells-evs-next-year/
Click to expand...
Thanks, OrientExpress! I've seen that article, but I don't see anything about cycle life there. I'm wondering where that data came from. Do you know?

Also, I will note the following from the article you linked:
PushEVs said:
Theoretically, the energy density of NCM 811 battery cells can reach 1.000 Wh/L,...
Click to expand...
That's very impressive!
Click to expand...

I can’t find a link right now, but I’ve seen similar numbers.

1250 to 1500 cycles for NMC without significant capacity fade even at 50 degrees Celsius. I believe it was in a Materials Today paper where they were talking about the strengths and weaknesses of various chemistries. The NCA batteries in a Tesla are apparently greater than 1500. LCO, LMO, and one more I can’t remember were less than 1000.
 
jonathanfields4ever said:
I can’t find a link right now, but I’ve seen similar numbers.

1250 to 1500 cycles for NMC without significant capacity fade even at 50 degrees Celsius. I believe it was in a Materials Today paper where they were talking about the strengths and weaknesses of various chemistries. The NCA batteries in a Tesla are apparently greater than 1500. LCO, LMO, and one more I can’t remember were less than 1000.
Click to expand...
O.K., thanks! I found something on CleanTechnical:

ncm811-vs-ncm523-cycle-life.png


I could even argue that graph points at 1400 cycles at 45C to 80% for NMC811.

And, as the article indicates, Dr. Jeff Dahn shows NMC cells with the potential to achieve over 4000 cycles (at 25:00 in the video):

[youtube]http://www.youtube.com/watch?v=5WpQh4kZ_MU[/youtube]

But I will note that Dr. Dahn's data is on NMC442, not 811.
 
RegGuheert said:
jonathanfields4ever said:
I can’t find a link right now, but I’ve seen similar numbers.

1250 to 1500 cycles for NMC without significant capacity fade even at 50 degrees Celsius. I believe it was in a Materials Today paper where they were talking about the strengths and weaknesses of various chemistries. The NCA batteries in a Tesla are apparently greater than 1500. LCO, LMO, and one more I can’t remember were less than 1000.
Click to expand...
O.K., thanks! I found something on CleanTechnical:

ncm811-vs-ncm523-cycle-life.png


I could even argue that graph points at 1400 cycles at 45C to 80% for NMC811.

And, as the article indicates, Dr. Jeff Dahn shows NMC cells with the potential to achieve over 4000 cycles (at 25:00 in the video):

[youtube]http://www.youtube.com/watch?v=5WpQh4kZ_MU[/youtube]

But I will note that Dr. Dahn's data is on NMC442, not 811.
Click to expand...

And the 2018 Leaf is NMC622 if I recall correctly. I don’t know how that bodes for cycle life, but I’m hopeful.
 
jonathanfields4ever said:
And the 2018 Leaf is NMC622 if I recall correctly. I don’t know how that bodes for cycle life, but I’m hopeful.
Click to expand...
Personally, I don't believe you can go by just the anode chemistry to estimate life, as I think lifetime is very manufacturer-specific. The reason is that much of the innovation in these batteries lies in the "special sauce" added to the electrolyte to poison the unwanted reactions that occur therein. As Dr. Dahn pointed out in the video I linked, these reactions are not only unwanted, but many of them are unknown. It can take a significant amount of research effort just to identify what is reacting and why. Once you know all that, it is still not obvious how to sufficiently limit the reaction from occurring over the range of voltages and temperatures desired for operation of the cell.
 
RegGuheert said:
jonathanfields4ever said:
And the 2018 Leaf is NMC622 if I recall correctly. I don’t know how that bodes for cycle life, but I’m hopeful.
Click to expand...
Personally, I don't believe you can go by just the anode chemistry to estimate life, as I think lifetime is very manufacturer-specific. The reason is that much of the innovation in these batteries lies in the "special sauce" added to the electrolyte to poison the unwanted reactions that occur therein. As Dr. Dahn pointed out in the video I linked, these reactions are not only unwanted, but many of them are unknown. It can take a significant amount of research effort just to identify what is reacting and why. Once you know all that, it is still not obvious how to sufficiently limit the reaction from occurring over the range of voltages and temperatures desired for operation of the cell.
Click to expand...

+1

We all talk like we know exactly what Nissan should be doing like we are experts when the reality is we have nothing but anecdotal evidence from our own experiences where we have rationalized away our faults and miscalculations to blame Nissan.

There are so many misconceptions here about BMS, TMS, and best case practices its really alarming. We are ignoring several basic ideologies while blaming unchangeable things like weather, public charging access, home charging options and the availability of free work place charging.

The HUGE VARIANCE in end user experiences no longer adhere to geographical advantages, but still exist.

Get a clue folks. No one is blameless here.
 
We all talk like we know exactly what Nissan should be doing like we are experts when the reality is we have nothing but anecdotal evidence from our own experiences where we have rationalized away our faults and miscalculations to blame Nissan.

There are so many misconceptions here about BMS, TMS, and best case practices its really alarming. We are ignoring several basic ideologies while blaming unchangeable things like weather, public charging access, home charging options and the availability of free work place charging.

The HUGE VARIANCE in end user experiences no longer adhere to geographical advantages, but still exist.

Get a clue folks. No one is blameless here.
Click to expand...

What crap. That could easily have been posted by Orient Express. What "several basic ideologies" are we "ignoring" exactly...? And how are the people who bought 2016 or 2017 Leafs to blame?
 
LeftieBiker said:
We all talk like we know exactly what Nissan should be doing like we are experts when the reality is we have nothing but anecdotal evidence from our own experiences where we have rationalized away our faults and miscalculations to blame Nissan.

There are so many misconceptions here about BMS, TMS, and best case practices its really alarming. We are ignoring several basic ideologies while blaming unchangeable things like weather, public charging access, home charging options and the availability of free work place charging.

The HUGE VARIANCE in end user experiences no longer adhere to geographical advantages, but still exist.

Get a clue folks. No one is blameless here.
Click to expand...

What crap. That could easily have been posted by Orient Express. What "several basic ideologies" are we "ignoring" exactly...? And how are the people who bought 2016 or 2017 Leafs to blame?
Click to expand...

Ok, lets go with your conclusions.

So how do we explain the huge disparity between drivers in the same climate? Just write it off as a massive variance in the battery fab quality?
 
I didn't post any "conclusions." Why the variance in SOH among drivers in the same region? We don't know. The drivers don't know either, and they aren't doing anything that Nissan has warned them not to do. It may be heating related to charging, but we don't know that yet. The 30kwh packs have a serious design flaw that appears to be causing excess degradation in a majority of the cars. That is Nissan's fault, not the drivers' fault.
 
LeftieBiker said:
I didn't post any "conclusions." Why the variance in SOH among drivers in the same region? We don't know. The drivers don't know either, and they aren't doing anything that Nissan has warned them not to do. It may be heating related to charging, but we don't know that yet. The 30kwh packs have a serious design flaw that appears to be causing excess degradation in a majority of the cars. That is Nissan's fault, not the drivers' fault.
Click to expand...


cars? cellphones? or any other device where we are required to manage the battery? It used to be simply low quality batteries. Not so much anymore.

The reality is we have traded battery longevity for convenience. We accept that unknowingly then blame whoever when our cellphones can't make it without a boost in the middle of the day 6 months down the line. But why? Because the battery used to go to bed at 60% before being recharged overnight to full for the next day .

We didn't understand the importance of avoiding 100% needlessly because it was simply much easier to plug it in at night and forget about it till morning. Way too much of a hassle to plug it in for an hour a few times a day.... WAY too much hassle.

But nothing I say will change your position. This I already know. It has always been the practice to assign 100% blame.... partial blame is not an option.
 
Since Nissan knowingly removed the charge to 80% option, and since both the Canary packs and the 30kwh packs degrade rapidly even when NOT charged to 100% and left sitting, you appear you have an accusation in search of a basis in reality.

BTW, it's very easy to not charge a cell phone to 100% most of the time. My first battery was still going strong at a year old, and only faded at 18 months after getting accidentally run down to 0%. Since we don't carry our cars with us, or charge them in our homes, it's quite a bit harder to charge a post '13 Leaf to 80% or less.
 
LeftieBiker said:
I didn't post any "conclusions."
Click to expand...

vs

LeftieBiker said:
The 30kwh packs have a serious design flaw that appears to be causing excess degradation in a majority of the cars. That is Nissan's fault, not the drivers' fault.
Click to expand...

Those look like conclusions to me.

Design flaw? Maybe, maybe a manufacturing issue. Majority of cars? I've not seen any reasonable statistics, only that some cars have a problem and other cars do not.
 
Change "design flaw" to just "flaw" and it's an observation, not a conclusion. Mayne it is a manufacturing issue, for all the difference it seems to make. You can think of this as an 'occasional lemon' problem, but so far we have only one, AFAIK, person posting good numbers for a 30kh pack. The rest of the ones posted here show rapid degradation.
 

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