How disappointed should I be that Nissan did not include liquid battery cooling on the Leaf E-Plus?

[WetEV]

Further, recent tests where DCFCs are used twice per day
to charge Nissan LEAFs driving in Phoenix have shown that the
difference in capacity loss due to fast charger use (as compared to an
otherwise identical case using Level 2 charging) after 50,000 miles of
driving is less than 3% [31].

[31] http://web.archive.org/web/20160317120429/https://avt.inl.gov/pdf/energystorage/DCFC_Study_FactSheet_50k.pdf

To me, this casts some doubt on whether this was a really valid test of DCFC,

Real cars tested in Phoenix? What exactly do you want?

Note, however, that the testing was just two QCs per day. One QC a month doesn't matter much. One QC a week doesn't matter much. One QC a day matters a little, not a lot. Two QCs a day starts to matter in Phoenix. Most people are far less than a QC per day, as a QC is a bother and an expense.

On Seattle versus "upstate NY" (with further clarification that was offered in this case, I think Albany/Saratoga Springs area)
- I am not very experienced with weather and climate data, but even just a glance shows that there is some (what seems to me) decent-sized variance in all-time summer monthly record highs among different towns, and between those towns and Seattle.

It's not the all time high records that matter. It is the effective battery temperature over time. The battery aging factor in the wiki is a fair approximation. And for that matter Seattle doesn't have a completely uniform climate.

A goal here for me (both for personal buying but also for industry analysis) is to understand, going into gen3 and so-on, whether, or to what extent, I think it might be a flat-out mistake for an automaker to offer passive or active air-cooling, and to understand this, part of the matter is to compare with liquid cooling (the link you provided does this, somewhat, but some of the other links provided elsewhereI'm not so sure).

As discussed, it's possible to argue that it's not a flat-out mistake but simply a matter of serving different markets and customer needs. One of several reasons I cringe when I see this argument is that I think an important principle in the vehicle business in North America as it plays out is that once a vehicle is let loose in the wild, it is quite possibly going to be subjected to all manner of conditions, even just on a very occasional long trip to another set of climate conditions, or in the hands of a 2nd or 3rd or 4th owner. While one can debate the wisdom of over-engineering a vehicle (and dramatically bumping the up-front price) so that it is likely to have great durability no matter what the abuse, I am hypothesizing that it's best to engineer an EV with the idea in mind that ultimately it will probably not always be kept (by owner practices) within a safe-for-the-passively-cooled-battery-longevity set of conditions.

Just what harm are you saving people from? Slightly faster capacity loss if they do something less than wise?

I'd rather have the safer passively cooled battery. Simpler and more reliable as well. Why am I wrong for wanting that? I understand why you want active cooling.

Something that I think a lot of people miss is that climates still matter with active cooling. Cool climates will still be better lifetime than warm, warm still better than hot, not until you get to very hot climates that there is a clear difference between active and passively cooled battery lifetimes.

 

[WetEV]

Also keep in mind that my story is for the 24 kWh LEAF. There are many good reasons to think that the 40 kWh, not to mention the 60 kWh LEAF battery will perform worse.

Ok, I'll bite.

Exactly why is the 60kWh battery worse than the 24kWh battery?

 

[jlsoaz]

Further, recent tests where DCFCs are used twice per day
to charge Nissan LEAFs driving in Phoenix have shown that the
difference in capacity loss due to fast charger use (as compared to an
otherwise identical case using Level 2 charging) after 50,000 miles of
driving is less than 3% [31].

[31] http://web.archive.org/web/20160317120429/https://avt.inl.gov/pdf/energystorage/DCFC_Study_FactSheet_50k.pdf

To me, this casts some doubt on whether this was a really valid test of DCFC,

Real cars tested in Phoenix? What exactly do you want?

Hi - You have cut the part of what I quoted that led to my my comment. The part that you cut was this:

"..While the nearly negligible impact of DCFC usage on battery
capacity fade may be surprising to some, it is important to point out
that DCFCs are used quite sparingly in our driver histories. Most
drivers use a DCFC less than once per month (Figure 6), and when
they are utilized, they typically charge the battery less than 60%
(Figure 9)..."

Anyway, while I suppose this discussion of DCFC in old technology passively cooled cars is somewhat relevant to my original question, I'm not sure it's really fully to the point. I was disappointed in Nissan seven years ago and unfortunately the degradation that I and others feared would happen did happen. Ok, so you've indicated that I am wrong to be disappointed. Ok, that's your view.

In the meantime, my question then is how much have things changed from a technology standpoint? Rapidgate, for one thing, leaves me concerned that things may not have changed that much.

 

[WetEV]

I was disappointed in Nissan seven years ago and unfortunately the degradation that I and others feared would happen did happen. Ok, so you've indicated that I am wrong to be disappointed. Ok, that's your view.

No, that's not my view. Yes the degradation was worse than expected. Not because of a lack of active cooling. Sure, there is about a 3:1 range of battery life because of climate with passive cooling. And you have the short stick. There is also about a 2:1 range of battery life because of climate with active cooling.

I see why you want active cooling. I would rather not have active cooling. Do you understand why?

 

[jlsoaz]

I was disappointed in Nissan seven years ago and unfortunately the degradation that I and others feared would happen did happen. Ok, so you've indicated that I am wrong to be disappointed. Ok, that's your view.

No, that's not my view.

My summary of your view was based in part on your rather forceful reply about an Achilles Heel. I don't have all day to sit here and wordsmith things, but sure, we should avoid putting words in others' mouths.

So, to re-state:
I was disappointed that Nissan failed to do more to protect the battery from degradation seven years ago, (not to mention related issues such as they failed to offer a larger battery option, and took longer than I thought was prudent to address this in the US market) Let me know if you think I was wrong to be disappointed.

[edit: addendum: I'll add: some have made the points that they are claimed to have done ok from a profit/loss standpoint. Ok. This is worth saying and does temper my disappointment somewhat. Also, my disappointment was not only in battery life concerns but in battery size, and how long it took them to offer some larger battery options and IMO some arguably tone-deaf approach to the dialogue with US consumers around battery size. On consideration, maybe some of my focus or over-focus here on degradation is tied in with the idea that if they are finally going to offer a bigger battery, and go through another round of asking early-adopters to hand over $40k, then maybe they could do more to err on the side of caution when it comes to vehicle residual values.]

Yes the degradation was worse than expected. Not because of a lack of active cooling.

Ok, what reason then? Are you going for that we should view the engineering as a combination package of design decisions (cell chemistry, pack architecture, nuances of these things, prioritization of safety, other considerations, etc.) or are you just saying there was some other simple clear reason?

Sure, there is about a 3:1 range of battery life because of climate with passive cooling. And you have the short stick. There is also about a 2:1 range of battery life because of climate with active cooling.

I don't understand what you are trying to say here.

I see why you want active cooling.

I think there have been signs this is half-true.

I would rather not have active cooling. Do you understand why?

I'm really not sure what makes you think I don't get it.

Overall:

While I do regard some aspects of this discussion as quite relevant, if I have summarized my point of view and it has fallen on deaf ears in my view, then I think it's best to just leave that part of the conversation alone, as I have achieved formulating what I think, and my goal is not to convince. If others see my own views in the same light, that is basically ok with me (aside from misportrayal of my own views that may take place, which is not ok).

In this case, I am concerned (not entirely convinced, but trying to investigate) that Nissan may have made an additional error on top of what were (IMO) past errors. Still, there's a lot I don't know, and maybe (hopefully) my concerns will be proven unfounded.

I seem to be having trouble conveying to you (in a way that is costing me a lot of time) and make a point that I'm fine with the idea that there are different strokes for different folks when it comes to product supplying and buying, but at the same time from a business strategy point of view I think it can be said that there are times when the context of the product and customer desires is such that it is debatable, from the standpoint of the long-term success of the company, to offer a certain product with or without certain features.

Perhaps the trouble in conveying is that we should step back and recognize that discussions that involve consumer preferences and seeing those preferences both aggregated and individually ... these discussions may be in some ways inherently difficult. I just wish that you would stop projecting onto me that I do not understand other consumers have different points of view and needs.

Maybe, ultimately, it will be very profitable for Nissan in the long-term to go with their announced path. I do hope so. With that being said, while some of this is of interest, some of it is getting *way* off-track as far as I'm concerned, so I'm going to re-summarize some of what actually interests me to address and discuss here.

I want to try to get a handle on and discuss the pros and cons of Nissan's recent decisions for this next round. My views are framed in light of what I regard as debatable decisions that the company made in the past.around battery size, size options, protection, and some significant misunderstanding in my view of some aspects of the US market. With the e+ I think they have finally largely addressed the when-new battery capacity issues. I'm trying to understand to what degree they have addressed the battery life protection and other issues. I think I do get that it is not as simple as one-size-fits-all-buyers, that there are really important considerations in cost, safety, complexity, maintenance, r&d budgets, marketing timing, ETC.

 

[WetEV]

My summary of your view was based in part on your rather forceful reply about an Achilles Heel.

A feature I want is something you call an "Achilles Heel". This is a productive discussion. :roll:

I was disappointed that Nissan failed to do more to protect the battery from degradation seven years ago, (not to mention related issues such as they failed to offer a larger battery option, and took longer than I thought was prudent to address this in the US market) Let me know if you think I was wrong to be disappointed.

One size fits all.
Doesn't.

Yes the degradation was worse than expected. Not because of a lack of active cooling.

Ok, what reason then? Are you going for that we should view the engineering as a combination package of design decisions (cell chemistry, pack architecture, nuances of these things, prioritization of safety, other considerations, etc.) or are you just saying there was some other simple clear reason?

Not everything is simple, and simple answers are often not even wrong, or just plain wrong. Or at best, partly correct.

Faster capacity loss in the early LEAFs outside of Phoenix and other hot places is mostly not because of active cooling.

If the battery never gets warmer than the cooling threshold, the active cooling never turns on. Never cools the battery. No improvement in battery life. Battery life in the coastal PNW for the 2011/2012 LEAFs wasn't the ~20 years expected, but more like 10 years to 70% best case. A TMS would never turn on in normal driving in the coastal PNW. So faster than expected capacity loss in the early cars in the PNW was not due to lack of active cooling.

If the battery sometimes gets slightly above the threshold a few days a year, the extra life from the cooling is likely a few days total. If the battery gets well above the threshold for two weeks every year, the extra life from cooling is perhaps a week or two a year. Or a few months faster over 12 years.

Hotter places, like Salt Lake City, UT, or Orlando, Fl, the economic case for active cooling is getting better. This was expected. Might save them $10-$15 a month in battery costs. That is starting to be noticeable.

The hottest of places is likely to have battery life shortened by years. This wasn't unexpected, this was known in advance. Might cost $40 or $50 or more a month in battery costs to have a passively cooled battery. Still, this might be acceptable to some to avoid the vampire drain of a TMS, and to gain higher reliability and safety. Not acceptable to everyone.

Sure, there is about a 3:1 range of battery life because of climate with passive cooling. And you have the short stick. There is also about a 2:1 range of battery life because of climate with active cooling.

I don't understand what you are trying to say here.

Based on climate and Arrhenius's rule, Phoenix battery life would be about 1/3 that of Seattle. With active cooling, Phoenix battery life would be about half of Seattle. This was known before the LEAF was a sketch on a napkin.

I would rather not have active cooling. Do you understand why?

I'm really not sure what makes you think I don't get it.

A feature I want is something you call an "Achilles Heel".

If you get it, then explain why someone (actually most people) might prefer passive cooling.

 

[johnlocke]

Arguing over active vs passive cooling in a Leaf is like using a bandaid to stop arterial bleeding. The real problem is Nissan's choice of battery chemistry. Leafs and Zoes in Europe do ok for battery life. Leafs in the US do not. That's due to higher average temps in the US. The Leaf and the Teslas are the only brands with large enough quantities of cars on the road for a long enough time periods to be able to draw meaningful data from. The problem could be the pouch cell configuration, battery chemistry, or lack of cooling. It doesn't really matter though. Leaf batteries just don't last in the US and that's reflected in their low resale values. It's not due to federal or state incentives being discounted as Teslas receive the same discounts but have far better resale values.

60KWH leafs may do better just due to fewer charge cycles for a given mileage but I doubt it. Changing to higher density cells without changing the cooling or chemistry is likely to offset that.

 

[WetEV]

That's due to higher average temps in the US.

Some parts of the US.

Leaf batteries just don't last in the US and that's reflected in their low resale values. It's not due to federal or state incentives being discounted as Teslas receive the same discounts but have far better resale values.

You buy a Tesla at MSRP.

You buy a LEAF at a discount from MSRP. Many of these discounts have been fairly large.

 

[evnow]

That's due to higher average temps in the US.

Some parts of the US.

Is there some comparison between Tesla's battery losses vs Leaf's losses in moderate climates (like in Seattle) ? How about in Europe ?

Leaf batteries just don't last in the US and that's reflected in their low resale values. It's not due to federal or state incentives being discounted as Teslas receive the same discounts but have far better resale values.

You buy a Tesla at MSRP.

You buy a LEAF at a discount from MSRP. Many of these discounts have been fairly large.

But also the battery issue. I've talked to a lot of people - here in Seattle - about Leaf's battery loss. When I suggest a Leaf, that's the first thing that used to come up - then I had to explain about the climate and finally tell them, anyway you can lease and not worry about the battery.

 

[jlsoaz]

[...] Leaf batteries just don't last in the US and that's reflected in their low resale values. [...]

At least part of the reason for the low resale values, in my opinion, is that the batteries provided lame gen1 EPA range (even when new)..
My thought before the vehicles were issued was that inevitably, as longer-range BEVs were issued, the gen1 short-range BEVS would not do that well in the resale marketplace.

I do think it seems useful to speculate that additional reasons for resale value concerns include degradation. Perhaps also other things contribute such as transparency issues in resale (how many bars? where from?). As well, perhaps the vehicle could have done better with some increased future-proofing effort from Nissan from the get-go (eg: for $x, the 2011 Leaf battery can be replaced with a battery that has 1.5 times the capacity).

Still, while the critical brainstorming exercise is interesting, I think things could have been worse in the used marketplace, so there are factors that helped it. For example, as far as I know, the vehicle does not have a problematic safety record. Also, as far as my experience went, while there were some aspects I did not like, it was pretty darned good for a gen1 BEV. For examples: decent smooth quiet acceleration, not that many little things going wrong, fairly spacious.

 

[jlsoaz]

My summary of your view was based in part on your rather forceful reply about an Achilles Heel.

A feature I want is something you call an "Achilles Heel". This is a productive discussion. :roll:

I was disappointed that Nissan failed to do more to protect the battery from degradation seven years ago, (not to mention related issues such as they failed to offer a larger battery option, and took longer than I thought was prudent to address this in the US market) Let me know if you think I was wrong to be disappointed.

One size fits all.
Doesn't.

Yes the degradation was worse than expected. Not because of a lack of active cooling.

Ok, what reason then? Are you going for that we should view the engineering as a combination package of design decisions (cell chemistry, pack architecture, nuances of these things, prioritization of safety, other considerations, etc.) or are you just saying there was some other simple clear reason?

Not everything is simple, and simple answers are often not even wrong, or just plain wrong. Or at best, partly correct.

Agreed.

Faster capacity loss in the early LEAFs outside of Phoenix and other hot places is mostly not because of active cooling.

I guess you mean mostly not because of _lack of_ active cooling.

If the battery never gets warmer than the cooling threshold, the active cooling never turns on. Never cools the battery. No improvement in battery life. Battery life in the coastal PNW for the 2011/2012 LEAFs wasn't the ~20 years expected, but more like 10 years to 70% best case. A TMS would never turn on in normal driving in the coastal PNW. So faster than expected capacity loss in the early cars in the PNW was not due to lack of active cooling.

This seems like splitting hairs. Ok, so it was due to lack of application of the active cooling when it might have helped.

If the battery sometimes gets slightly above the threshold a few days a year, the extra life from the cooling is likely a few days total. If the battery gets well above the threshold for two weeks every year, the extra life from cooling is perhaps a week or two a year. Or a few months faster over 12 years.

Hotter places, like Salt Lake City, UT, or Orlando, Fl, the economic case for active cooling is getting better. This was expected. Might save them $10-$15 a month in battery costs. That is starting to be noticeable.

The hottest of places is likely to have battery life shortened by years. This wasn't unexpected, this was known in advance. Might cost $40 or $50 or more a month in battery costs to have a passively cooled battery. Still, this might be acceptable to some to avoid the vampire drain of a TMS, and to gain higher reliability and safety. Not acceptable to everyone.

This thread title specifically refers to "liquid" cooling, not "active" cooling. Are you trying to say that your points and calculations refer to all active cooling, including liquid cooling, because that is what it sounds like to me, at times. Are you referring only to what was known and heavily researched from the early Leaf data? Or maybe it is case by case, depending on the point in the discussion. I am not trying to be cute - I am finding it confusing that you do not specify type of active cooling, and do not specify if you are talking about early Leaf data or something else.

Sure, there is about a 3:1 range of battery life because of climate with passive cooling. And you have the short stick. There is also about a 2:1 range of battery life because of climate with active cooling.

I don't understand what you are trying to say here.

Based on climate and Arrhenius's rule, Phoenix battery life would be about 1/3 that of Seattle. With active cooling, Phoenix battery life would be about half of Seattle. This was known before the LEAF was a sketch on a napkin.

With respect to Arrhenius's rule, something I've been meaning to ask - if good thermal management does a really good job of keeping the battery within certain temperatures, then doesn't that mean that the vehicle battery won't suffer much (if any) degradation that is attributable to the climate of the surrounding area? Perhaps in the sentence above, you are trying to say it applied only to the Leaf and not to other vehicles? Are you assuming a type of active cooling that is not that effective, or perhaps a battery chemistry or architecture or other factors that are not helped that much by active cooling?

I was able to obtain this slide:

[edited to post a link with clear credit and some comments]

http://jlaz.com/Files/2015_battery_pia/2015_PIA_battery_chart.html

This was presented at a Tesla owners forum in 2015. I communicated with the creator and the three colors and shapes I believe are in degrees fahrenheit. If hotter local climates were impacting battery life, one would expect to see more orderly groupings of the different shapes, with blue diamonds at top. The conclusion that some would draw was that local climate was not influencing the battery life at all, or by much. We should bear in mind that there are many other factors.

I realize that one slide from 2015 does not provide us with enough information, and I personally think it's possible that a deeper longer-term analysis of Model S over many years could reveal that local climate might have some impact. It's hard to say. But this discussion seems (to me) to have been characterized by a nearly complete (or total) absence of recent, robust, empirical and clearly relevant data across different factors such as driver behavior, climate, chemistry, exact thermal management approach, etc. So, if others have any such data, or some pieces, that might be helpful.

I would rather not have active cooling. Do you understand why?

I'm really not sure what makes you think I don't get it.

A feature I want is something you call an "Achilles Heel".
If you get it, then explain why someone (actually most people) might prefer passive cooling.

I have already done this, and you know it. This makes me concerned that my time is not respected, and that my comments are unheeded or mangled. In any event:

- Passive cooling is desirable in that it is very simple. Simplicity can in theory potentially lead to lower maintenance costs, fewer repair visits, higher customer satisfaction and lower up-front cost. Simplicity can also be lower weight, and as far as I know, in this case it is, and that can help both with range and overall vehicle performance. Passive cooling may in some ways as well be safer, such as possibly reducing the risk of thermal runaway in some situations. I would be curious if in the end the Leaf record on this last point has born out. It may also be a desirable trait for drivers in additional ways that I'm not as aware. Perhaps reduced noise, perhaps just peace of mind, though that is probably more tied-in to the things I've named. Passive cooling may also fit nicely with certain driver preferences, such as those drivers who prefer not to use DCQC much if at all, and if they don't mind that the vehicle value-retention may be somewhat negatively impacted by the fact that it should likely not be sold to different drivers or into some geographies.

Other points:
- As to my use of the phrase Achilles Heel, I believe that the 2011-2015 (or so) Leafs had two of them: inadequate range for too many customers in the US markets, and inadequate protection of the battery. I think both of these concerns have born out, to an extent, in sales figures over the years, and in used vehicle values.
- As far as I can tell, the benefits of liquid cooling, as implemented and born out on some of the gen1 vehicles (Tesla, Volt) are IMO improperly being given short shrift here.
- As far as the claim of low DCQC frequency amongst drivers, and sticking close to home, this is a matter of degree, but also somewhat a matter of timing and battery size. As time passes, as more DCQC is available, as battery size increases, and as lives and habits change, it is natural for some drivers, even if they thought at first they would charge seldom, to wonder if they can go further from home, and in some cases just use the quicker charging, if needed. Many gasoline vehicle drivers may not take the car far afield on a daily commute, but this does not mean they give up their right occasionally to take a longer trip or refuel quickly. I may be wrong, but it seems to me I can remember one or two Nissan salesperson comments around 2010-2011 trying to help me see using the Leaf robustly, without so much concern about modifying my behavior, as I might a gasoline vehicle.
- I thought the point made here recently as to used vehicle values was a powerful one, and is prominent on my mind when I go to buy a used vehicle myself.
- I thought the point made as to higher temperatures overall in the US than in Europe seemed worth considering.
- I do agree that my perspective may a bit skewed by geography as well as by time (i.e.: I was looking for which manufacturers installed what I consider to be good battery protection in 2011. This rule of thumb helped me understand how things played out at the time, but may not be as helpful now).
- I understand that liquid cooling (and within that, I'm sure there are variations) may not be the best strategy for 2019, or even 2015. An example might be the Toshiba battery chemistry? I haven't seen those mentioned much for small EVs, maybe there is a density issue. Perhaps the latest battery chemistry, architecture, and other features of the latest Leaf is so strongly resistant to degradation from heat that I have much less to worry about than I realize, even in Arizona. (Rapidgate might call that into question?)

 

[WetEV]

Faster capacity loss in the early LEAFs outside of Phoenix and other hot places is mostly not because of active cooling.

I guess you mean mostly not because of _lack of_ active cooling.

Correct.

If the battery never gets warmer than the cooling threshold, the active cooling never turns on. Never cools the battery. No improvement in battery life. Battery life in the coastal PNW for the 2011/2012 LEAFs wasn't the ~20 years expected, but more like 10 years to 70% best case. A TMS would never turn on in normal driving in the coastal PNW. So faster than expected capacity loss in the early cars in the PNW was not due to lack of active cooling.

This seems like splitting hairs. Ok, so it was due to lack of application of the active cooling when it might have helped.

No.

Battery cooling and heating has threshold(s). If the battery temperature never ever exceeds the temperature threshold where the cooling would turn on, then the cooling system has exactly zero effect on battery temperature and thus battery capacity loss. There are limits on how low of threshold can be for cooling. Too much cooling leads to condensation.

The most aggressive cooling system I'm aware of is the Chevy Volt. It starts cooling if the battery exceeds 30C. For the year and a bit that I could monitor my 2012 LEAF with a LeafSpy like application, the battery temperature never went over 30C. My 2014 has been over 30C. In the summer. On a hot day wiith 3 QCs. I probably lost an extra half a day of battery life on that day if compared with a hypothetical actively cooled LEAF with a 30C threshold. I'm not heart broken.

This thread title specifically refers to "liquid" cooling, not "active" cooling. Are you trying to say that your points and calculations refer to all active cooling, including liquid cooling, because that is what it sounds like to me, at times. Are you referring only to what was known and heavily researched from the early Leaf data? Or maybe it is case by case, depending on the point in the discussion. I am not trying to be cute - I am finding it confusing that you do not specify type of active cooling, and do not specify if you are talking about early Leaf data or something else.

Active cooling might mean forced cooled air, as a few cars have. Or cabin air, which is often cooler in the summer and warmer in the winter, such as the original Toyota Prius. Both of these are slightly better for battery life than passive cooling. Also get some battery heating in the winter, and mostly "for free".

I'm not aware of any liquid passively cooled BEVs. Are there any?

I don't understand what you are trying to say here.

Based on climate and Arrhenius's rule, Phoenix battery life would be about 1/3 that of Seattle. With active cooling, Phoenix battery life would be about half of Seattle. This was known before the LEAF was a sketch on a napkin.

With respect to Arrhenius's rule, something I've been meaning to ask - if good thermal management does a really good job of keeping the battery within certain temperatures, then doesn't that mean that the vehicle battery won't suffer much (if any) degradation that is attributable to the climate of the surrounding area?

That is an interesting idea, if I get what you are implying. If you don't care about minimum cost, but instead care about only performance, then why not heat the battery almost to the point of where cooling was desired? Then the outside climate wouldn't have any impact on battery life.

If you are trying to minimize total cost, then you wouldn't do that. Battery life would be better and 0-60 times would be worse in cooler climates. Depends on goals and values.

I was able to obtain this slide:
http://jlaz.com/Files/2015_slide.png

404

- Passive cooling is desirable in that it is very simple. Simplicity can in theory potentially lead to lower maintenance costs, fewer repair visits, higher customer satisfaction and lower up-front cost. Simplicity can also be lower weight, and as far as I know, in this case it is, and that can help both with range and overall vehicle performance. Passive cooling may in some ways as well be safer, such as possibly reducing the risk of thermal runaway in some situations. I would be curious if in the end the Leaf record on this last point has born out.

As far as I know, there have been no LEAF battery fires. Unlike both Tesla and Chevy Volt.

It may also be a desirable trait for drivers in additional ways that I'm not as aware. Perhaps reduced noise, perhaps just peace of mind, though that is probably more tied-in to the things I've named. Passive cooling may also fit nicely with certain driver preferences, such as those drivers who prefer not to use DCQC much if at all, and if they don't mind that the vehicle value-retention may be somewhat negatively impacted by the fact that it should likely not be sold to different drivers or into some geographies.

"Value-retentation" is important to people who are not as concerned with value. People who are concerned with value would buy a car and own until the wheels fall off. Probably used rather than new. For someone in a cool climate that wants a car for local trips only, a 2011 LEAF from a warmer climate with 4 bars lost could be very cheap. Could last a long time, in a cool climate, with minimal range needed. Sounds like real value to me.

- As to my use of the phrase Achilles Heel, I believe that the 2011-2015 (or so) Leafs had two of them: inadequate range for too many customers in the US markets,

So how many thousands of dollars would have been added to the cost and price to get "adequate" range in 2011?

and inadequate protection of the battery.

Battery life wasn't adequate for the early LEAFs, 2011-early 2013. But not because of "inadequate protection of the battery".

- As far as I can tell, the benefits of liquid cooling, as implemented and born out on some of the gen1 vehicles (Tesla, Volt) are IMO improperly being given short shrift here.

I don't agree that the better life of other cars was ONLY due to active liquid cooling. Mostly you need to find a different cause. Yes, Phoenix is somewhat different, active cooling has a real benefit there, and other very hot climates.

I'm unaware of any passive liquid cooled BEVs or PHEVs.

As far as the claim of low DCQC frequency amongst drivers, and sticking close to home, this is a matter of degree, but also somewhat a matter of timing and battery size. As time passes, as more DCQC is available, as battery size increases, and as lives and habits change, it is natural for some drivers, even if they thought at first they would charge seldom, to wonder if they can go further from home, and in some cases just use the quicker charging, if needed.

Claim? Observation.

Here is a novel way to estimate. There are about 100 DCQC CHAdeMO stations in Washington State. According to Plugshare currently 2 are busy. About how many LEAFs do you think there are in Washington State? As far as I can tell, it is around 10,000, perhaps more. Total EVs registered is 42,542 as of December 2018:

http://www.westcoastgreenhighway.com/pdfs/Map_WAEVRegistrationByCounty.pdf

If two stations are always busy charging LEAFs 24 hours a day, they could DCQC about 3 LEAFs per hour, or 36 LEAFs twice a day, or 72 LEAFs once a day. Or 10,000 LEAFs once every 138 days.

If every station was busy charging a LEAF 24 hours a day, 7 days a week, they could charge about once per day.

Not every car using a DCQC is a LEAF, and there clearly isn't even close to enough DCQC capability to support more than occasional changing by most LEAF cars.

 

[jjdoe]

We paid $19k for our year old SL, with every option. This was the typical price.
I've read the batteries will last 10 years. I'm buying a 1018 next month, for the Pro drive. But we don't have heat issues in Atlanta like you do in AZ.

 

[jlsoaz]

We paid $19k for our year old SL, with every option. This was the typical price.
I've read the batteries will last 10 years. I'm buying a 1018 next month, for the Pro drive. But we don't have heat issues in Atlanta like you do in AZ.

Thanks, good to know.

 

[cwerdna]

I stumbled across https://www.facebook.com/watch/?v=257360088481234 in my FB feed today. Brian, the Nissan marketing exec in the video (who also came to present at 2+ EVents in the Bay Area, including a reveal of the '18 Leaf before it was even available for test drive) in tip #2 says "Heat can reduce the overall life of the Lithium Ion battery" and says to store your EV in a garage or under cover in summer months. :lol:

 

[Evoforce]

I stumbled across https://www.facebook.com/watch/?v=257360088481234 in my FB feed today. Brian, the Nissan marketing exec in the video (who also came to present at 2+ EVents in the Bay Area, including a reveal of the '18 Leaf before it was even available for test drive) in tip #2 says "Heat can reduce the overall life of the Lithium Ion battery" and says to store your EV in a garage or under cover in summer months. :lol:

:lol: :lol: I also have to add to this discussion that Kia Souls in Arizona climate with cabin air battery cooling are a fail.

 

[jlsoaz]

I stumbled across https://www.facebook.com/watch/?v=257360088481234 in my FB feed today. Brian, the Nissan marketing exec in the video (who also came to present at 2+ EVents in the Bay Area, including a reveal of the '18 Leaf before it was even available for test drive) in tip #2 says "Heat can reduce the overall life of the Lithium Ion battery" and says to store your EV in a garage or under cover in summer months. :lol:

:lol: :lol: I also have to add to this discussion that Kia Souls in Arizona climate with cabin air battery cooling are a fail.

Both helpful IMO, thx.

 

[jlsoaz]

In case anyone finds it of interest, I have updated this page with some more charts (by permission) and a few notes:

http://jlaz.com/Files/2015_battery_pia/2015_PIA_battery_chart.html
Study of Tesla Model S Battery Pack and Local Climate

 

[jlsoaz]

Based on climate and Arrhenius's rule, Phoenix battery life would be about 1/3 that of Seattle. With active cooling, Phoenix battery life would be about half of Seattle. This was known before the LEAF was a sketch on a napkin.

With respect to Arrhenius's rule, something I've been meaning to ask - if good thermal management does a really good job of keeping the battery within certain temperatures, then doesn't that mean that the vehicle battery won't suffer much (if any) degradation that is attributable to the climate of the surrounding area?

That is an interesting idea, if I get what you are implying. If you don't care about minimum cost, but instead care about only performance, then why not heat the battery almost to the point of where cooling was desired? Then the outside climate wouldn't have any impact on battery life.

If you are trying to minimize total cost, then you wouldn't do that. Battery life would be better and 0-60 times would be worse in cooler climates. Depends on goals and values.

Hi - I'm not sure I was understood, and there is enough misunderstanding going on, and enough expenditure of time on all sides, that I'll just confine myself to this point.

I was trying to ask what I think is a very basic straightforward question - if good thermal management keeps the battery temperatures within certain parameters, then why is it assumed that a vehicle with good thermal management would go through loss of range comparable to what you're saying? Why would battery life of a Phoenix pack protected by good thermal management have "half" the life of a Seattle pack? As far as the Phoenix pack is concerned, from its confined point of view, the conditions it has experienced have been not that much different from those of the Seattle pack, are they not?

Perhaps your definition of "active cooling" is not the same as my definition of good or even decent thermal management? I really don't know, but you seem to be penciling in some less costly relatively ineffective solution, or perhaps penciling in a chemistry that won't benefit as much from cooling. I get that safety and other factors are important, but for a moment l'd like to focus on being more clear that there are various types of active cooling, and I'm educated-guessing it will not be as prohibitively expensive as you seem to think to get cooling into place which would do a more effective job than you seem to think of preserving vehicle range.

I was able to obtain this slide:
http://jlaz.com/Files/2015_slide.png

404

Sorry, my bad, here is a link that hopefully now will work. Note that the information here is old and perhaps there are much better solutions now. Still, we can see that even in 2015 Tesla's early liquid cooling solutions appeared (at least in the early data) to be quite effective at preserving the battery.

http://jlaz.com/Files/2015_battery_pia/2015_PIA_battery_chart.html

 

[jlsoaz]

To summarize my own thoughts at this time:

- I wasn't able to get an answer about setting up a poll on this or a related topic. A poll would not be scientific but might help us move a little bit more toward having a bit more granular understanding or breakdown of what is wanted by various drivers.
- Good to see the increase to 60+ kWh. It's much later than I had wanted as a driver, and this lateness reduces the chances that I personally can consider buying the vehicle (since the used Bolt prices will come down to my level so much sooner) but even if it's just in the abstract, it's still good to see.
- Now that the range question is better-addressed, IMO, this leaves the question of at what rate and in what situations will the battery degrade.
- We see RapidGate and perhaps some other indications that the Leaf will consider to lag Tesla in the area of degradation.
- some of the feedback I got here seemed (in my view) to give short shrift to the advantages of liquid cooling and other good pack architecture.
- On a related note, there didn't seem to be a good summary out there showing a comparison of the old Leaf to the Tesla, so I pulled together some information and posted it:
http://jlaz.com/Files/2015_battery_pia/2015_PIA_battery_chart.html
- Pack architecture seems to have changed, and probably chemistry as well. So, keeping an open mind, it remains to be seen what will happen, and where, and by how much. I personally am guessing that the issues will still be there to a large-enough degree to still impact sales in some areas, but we'll see.
- I'm not sure if anyone raised the issue, but I'm wondering as to whether there are laws which govern offering the same model across different regions, and to what extent Nissan's decisions are impacted by this. I can't help but wonder if Nissan has chosen or would be well-served to choose to not sell vehicles into certain hot climate areas, and to help with transparency as to used Leaf sales and where the battery has been used.
- To this day, as of Q1 2019, Tesla is still the only manufacturer which has made a highly-demanded longer-range BEV widely available in the US. There are a few caveats to this (such as gaging whether and how Chevy has managed to tamp down on supply and demand for the Bolt while Tesla tries to manage with too many orders), but if NIssan's longer-range Leaf will be made widely available, I suppose it could be the second.
- I doubt that Leaf sales overall will remain at the top of the heap for that much longer. Some points are sometimes made about the sales success of the program, and there is some validity to that, but I think some points should also be discussed as to whether the sales numbers really were what Nissan originally envisioned and, if not, then what lessons could have been learned from that.
- Some of the rhetoric of the discussion here was unfortunately reminiscent in my view of the rhetoric I used to hear around 2009-2013 as to the early Leaf battery degradation issues. This included a somewhat strange disinclination to specify whether one is talking about active air cooling, with fans working on ambient air or with a/c, or whether one is talking about liquid cooling, or something else (Piezo cooling?).
- With all that being said, the conversation has served to remind me of the safety excellence of the Leaf record along with other possible advantages to thermal management other than liquid cooling. This seems important to bear in mind in various ways.
- As well, we discussed the question of different buyers wanting different things. Should the the lack of range-preserving liquid cooling on the Leaf be seen as a strategic decision error by the company, or was it the case that it should simply be seen as a question of serving certain buyers and not others? I'm still not entirely sure where I fall on this, though I do have some strong views on aspects of it, such as including that if Nissan knows a battery will degrade extremely in some areas and in certain use patterns, then in my view it should not sell them into those situations, and should perhaps do more (or maybe it already has) to consider the information transparency needs of buyers of used Leafs. My views are clouded, for one thing, by my disappointment in the decision not to offer much larger batteries much earlier on. My views are also clouded by some additional off-putting discussion here. off-putting experiences here including being accused of projecting my personal buying needs onto a broader discussion beyond what was called for, which would have some measure of validity if or to the extent true, but which also seems to come from some who themselves seem to me possibly to be projecting their own preferences onto a broader summary discussion.
- In any event, for my own buying needs, as the marketplace finally fills up with a few longer-range better-priced BEV options, it will become a somewhat better buyer's market over the next 10 years. Due to the vehicle being 2+ years behind Chevy Bolt, aside from differences in battery preservation approaches, the Leaf e+ may not be a front-runner for me.
- Separately, for my own attempt to hope good things for Nissan and EV sales in general, and to figure out if they have once again partially impressed but partially disappointed, I'm not sure. Will they have high or leading sales volumes along with widespread consistent good customer satisfaction and will they reduce or eliminate some of the cases of extreme customer dissatisfaction they had before? I guess they might, though in my opinion Rapidgate and one or two other things raise questions.