Lizard Pack Holding Up

ahagge said:

LeafMuranoDriver said:

ahagge - How many miles per month are you driving? From the charts, it looks around 4,000 to 6,000 per month.

I think the high mileage is what is keeping the stats up. Once you start driving very little, they seem to drop quite rapidly, then level out.

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Sorry for the delayed response, I'm not on as frequently these days.

To answer your question, I'm putting about 16,000 miles/year on the vehicle. At least 1,000 miles per month, every month (but no more than about 1,500 and certainly not in the 4k-6k range!).

FYI, here's the graph, updated through 10/28/16:

What I find interesting (and disheartening) now is that even though the weather has cooled significantly, the battery is losing capacity at an increased rate.

Sigh.

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Thanks for the data.
I think there are two types of capacity loss in this data.
Unrecoverable loss caused by battery usage times/mileages and recoverable loss caused by yearly low temperature in the winter.
In September to January, capacity loss looks like twice as normal because above losses accumulate and in February to August, capacity loss cancel out and up down pretty much go to side way.

I am glad I did not see the third type of huge unrecoverable capacity loss caused by high temperature in the August to September usually find in the First generation of the Leaf battery.

ht2 said:

Thanks for the data.
I think there are two types of capacity loss in this data.
Unrecoverable loss caused by battery usage times/mileages and recoverable loss caused by yearly low temperature in the winter.
In September to January, capacity loss looks like twice as normal because above losses accumulate and in February to August, capacity loss cancel out and up down pretty much go to side way.

I am glad I did not see the third type of huge unrecoverable capacity loss caused by high temperature in the August to September usually find in the First generation of the Leaf battery.

Click to expand...

there is also another possibility to consider. I found that the more you drive your LEAF, the better the battery numbers become. This has been demonstrated several times by people getting huge mileage on their LEAF before losing a bar, etc.

Now we have known that cycling your pack regularly boosts the numbers. Now whether the numbers are valid or not is anyone's guess but it does result in better top end pack balancing so what does this have to do with seasonal changes? Winter time generally means less efficient driving. its colder, rainier, etc. This means that your pack is cycling deeper than in Summer without changing your driving habits.

The other thing is how much of a difference does it make?



Here is some recent history on my LEAF. the column "public charges" is kwh received. now I don't differentiate between types of charges but that is a fast charge and you notice the immediate jump in stats?
Now if you look at the GID /ahr available this is only filled out when the charge cycle is completed. you can see two stretches, one of 4 days with minimal change in stats and another of 7 days with a much more significant jump in the numbers. Both stints of complete charges have relatively similar distances but I also have another example of 7 days in a row charging to full but with distances running 20 to 35 miles per day and again, no major changes in the numbers.

DaveinOlyWA said:

ht2 said:

Thanks for the data.
I think there are two types of capacity loss in this data.
Unrecoverable loss caused by battery usage times/mileages and recoverable loss caused by yearly low temperature in the winter.
In September to January, capacity loss looks like twice as normal because above losses accumulate and in February to August, capacity loss cancel out and up down pretty much go to side way.

I am glad I did not see the third type of huge unrecoverable capacity loss caused by high temperature in the August to September usually find in the First generation of the Leaf battery.

Click to expand...

there is also another possibility to consider. I found that the more you drive your LEAF, the better the battery numbers become. This has been demonstrated several times by people getting huge mileage on their LEAF before losing a bar, etc.

Now we have known that cycling your pack regularly boosts the numbers. Now whether the numbers are valid or not is anyone's guess but it does result in better top end pack balancing so what does this have to do with seasonal changes? Winter time generally means less efficient driving. its colder, rainier, etc. This means that your pack is cycling deeper than in Summer without changing your driving habits.

The other thing is how much of a difference does it make?



Here is some recent history on my LEAF. the column "public charges" is kwh received. now I don't differentiate between types of charges but that is a fast charge and you notice the immediate jump in stats?
Now if you look at the GID /ahr available this is only filled out when the charge cycle is completed. you can see two stretches, one of 4 days with minimal change in stats and another of 7 days with a much more significant jump in the numbers. Both stints of complete charges have relatively similar distances but I also have another example of 7 days in a row charging to full but with distances running 20 to 35 miles per day and again, no major changes in the numbers.

Click to expand...

I tried zooming in on that spreadsheet and still couldn't read the numbers. I can read parts of them but they are difficult to make out with any certainty. Is there a downloadable version available, or is there a better way to look at them that I'm not trying?

retrodog said:

DaveinOlyWA said:

ht2 said:

Thanks for the data.
I think there are two types of capacity loss in this data.
Unrecoverable loss caused by battery usage times/mileages and recoverable loss caused by yearly low temperature in the winter.
In September to January, capacity loss looks like twice as normal because above losses accumulate and in February to August, capacity loss cancel out and up down pretty much go to side way.

I am glad I did not see the third type of huge unrecoverable capacity loss caused by high temperature in the August to September usually find in the First generation of the Leaf battery.

Click to expand...

there is also another possibility to consider. I found that the more you drive your LEAF, the better the battery numbers become. This has been demonstrated several times by people getting huge mileage on their LEAF before losing a bar, etc.

Now we have known that cycling your pack regularly boosts the numbers. Now whether the numbers are valid or not is anyone's guess but it does result in better top end pack balancing so what does this have to do with seasonal changes? Winter time generally means less efficient driving. its colder, rainier, etc. This means that your pack is cycling deeper than in Summer without changing your driving habits.

The other thing is how much of a difference does it make?



Here is some recent history on my LEAF. the column "public charges" is kwh received. now I don't differentiate between types of charges but that is a fast charge and you notice the immediate jump in stats?
Now if you look at the GID /ahr available this is only filled out when the charge cycle is completed. you can see two stretches, one of 4 days with minimal change in stats and another of 7 days with a much more significant jump in the numbers. Both stints of complete charges have relatively similar distances but I also have another example of 7 days in a row charging to full but with distances running 20 to 35 miles per day and again, no major changes in the numbers.

Click to expand...

I tried zooming in on that spreadsheet and still couldn't read the numbers. I can read parts of them but they are difficult to make out with any certainty. Is there a downloadable version available, or is there a better way to look at them that I'm not trying?

Click to expand...

oh sorry. first two attempts were too big so had to shrink it. site restrictions are a bit over the top.


https://www.facebook.com/groups/1499072903728825/permalink/1599617557007692/?comment_id=1599928306976617&comment_tracking=%7B%22tn%22%3A%22R%22%7D

here is link to full size file on Facebook. its a public site so you should be able to see it as long as you have a FB account

Aussie said:

The original battery on my 2011 SL was replaced at the start of March this year. The replacement Lizard stats have recently been dropping like a stone. Capacity is now at 61.66AHr, SOH = 96% and Hx = 92.48. As others have mentioned, capacity was glued at 66.141 for almost 5 months (until mid July) and then has dropped far too quickly for my liking. Since battery replacement I have done just over 5000 miles of mostly day-to-day commuting.

I live in Dallas, TX, so we do get long, hot summers. The car is always parked in a garage. During the week I park on an upper level in the morning (to get the breeze whilst the temp is <90F), then move to the basement at lunchtime (where it tends to be a little cooler). Overnight it is parked in a basement and charged to 80% most days, and rarely to 100%. Observed pack temps only exceeded 100F a few times over summer, even with the hot weather we had.

Are these values consistent with those seen by others on the forum? It all seems a little concerning and isn't boding well for pack longevity.

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An update on my battery capacity performance. Winter hasn't slowed the capacity drop-off.

My 2014 Leaf does not recalculate SOH and Hx values if battery is colder than 15C (less than 5 bars).

I imagine getting a good result will be very hard due to cold chemistry.
And there is not a lot of degradation below that temperature.

Also in summer I went down to 90% (fluctuating +/- 0,5% for 3-4 months). Before winter it went up
to 95% and fluctuated there for a month until it got too cold and now stuck at 95.07%.

It appears with chilly temperatures BMS gets better results than with very warm battery (6 bars).
Once I got to 5 bars after multiple DC charges and Hx changed like 0.03 :lol:

I take 95% (both Hx and SOH) with 5% steps. Those readings are not even close to 1% precision.
My summer/winter difference is the proof.

tkdbrusco said:

I'd be willing to bet that there's a few late 2014 production models that got lizard batteries but I think there's really no way to know for sure if your has one unless you ran some readings when it was new and noticed a 292 GID reading.

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Based on your statement, I wonder if I have a lizard even with a 1/14 build date. LeafSpy indicated a SOC of 103% and GIDs of 292 several months and a couple thousand miles after purchase.

IBeLeaf2 said:

tkdbrusco said:

I'd be willing to bet that there's a few late 2014 production models that got lizard batteries but I think there's really no way to know for sure if your has one unless you ran some readings when it was new and noticed a 292 GID reading.

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Based on your statement, I wonder if I have a lizard even with a 1/14 build date. LeafSpy indicated a SOC of 103% and GIDs of 292 several months and a couple thousand miles after purchase.

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You might have gotten lucky. I think the 292 is only a number derived from Lizard packs. Either way, your pack is holding up well and your climate probably has a lot to do with it. Just got a 259 reading on mine today.

SOH down to 94% after 10 months and 18,000 miles, 60.5 Ahr, pretty much the same climate/driving/charging patterns as the original pack, hard to tell as I didn't have LeafSpy at the time but at the high level the degradation seems to be tracking close to the original pack which was losing about 8% annually, considering there was no loss for the first 4-5 months/8k miles presumable due to the hidden buffer in these new packs I might see it dropping faster in the future now that buffer is gone. Not entirely unexpected, but I don't really care much at this point.

SOH is up to 95% with warmer temps after 1 year and 23k miles, it does bode well with the title of this topic. The upcoming summer will be a real test as I've now burnt through the top buffer.

Mod note: For anyone looking for the prior conversation about one of our newest members I've moved that conversation to http://www.mynissanleaf.com/viewtopic.php?f=6&t=23748

Please feel free to continue discussions about tech here and welcoming new users there.

IBeLeaf2 said:

tkdbrusco said:

I'd be willing to bet that there's a few late 2014 production models that got lizard batteries but I think there's really no way to know for sure if your has one unless you ran some readings when it was new and noticed a 292 GID reading.

Click to expand...

Based on your statement, I wonder if I have a lizard even with a 1/14 build date. LeafSpy indicated a SOC of 103% and GIDs of 292 several months and a couple thousand miles after purchase.

Click to expand...

I find it unlikely a 1/14 build month '14 Leaf has the "lizard battery" given the announcement at http://www.mynissanleaf.com/viewtopic.php?f=4&t=17168.

It may be wishful thinking that any '14s have it.

cwerdna said:

IBeLeaf2 said:

tkdbrusco said:

I'd be willing to bet that there's a few late 2014 production models that got lizard batteries but I think there's really no way to know for sure if your has one unless you ran some readings when it was new and noticed a 292 GID reading.

Click to expand...

Based on your statement, I wonder if I have a lizard even with a 1/14 build date. LeafSpy indicated a SOC of 103% and GIDs of 292 several months and a couple thousand miles after purchase.

Click to expand...

I find it unlikely a 1/14 build month '14 Leaf has the "lizard battery" given the announcement at http://www.mynissanleaf.com/viewtopic.php?f=4&t=17168.

It may be wishful thinking that any '14s have it.

Click to expand...

Thanks for your thoughts on this. I didn't see anything on the first or last page of the topic you referred to which seemed to fit with my question though. Is there a specific quote you could point me to?

I wasn't doing much wishful thinking, just trying to determine why my battery is doing so well compared to others who have lost bars.

As I said originally, I did see 292 GIDs in LeafSpy. The opinion had been stated that 292 would indicate a "lizard" pack. After 37months and 55K miles it still shows 282-284 GIDs when charged.
Today I drove 82 miles round trip in 2.1 hours (avg. speed 40mph) and had 15 miles left on the GOM when I plugged in at home. I wasn't using LeafSpy so I can't provide the GID's.

Any ideas why this would be?
Are there others out there with similar battery statistics?

correction made to recent GID numbers. 282-284 is correct not 382-384. Now that would be wishful thinking :lol:

IBeLeaf2 said:

cwerdna said:

IBeLeaf2 said:

Based on your statement, I wonder if I have a lizard even with a 1/14 build date. LeafSpy indicated a SOC of 103% and GIDs of 292 several months and a couple thousand miles after purchase.

Click to expand...

I find it unlikely a 1/14 build month '14 Leaf has the "lizard battery" given the announcement at http://www.mynissanleaf.com/viewtopic.php?f=4&t=17168.

It may be wishful thinking that any '14s have it.

Click to expand...

Thanks for your thoughts on this. I didn't see anything on the first or last page of the topic you referred to which seemed to fit with my question though. Is there a specific quote you could point me to?

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From the OP of that thread made June 27, 2014:

BBrockman said:

I’m happy to be back to provide a long-awaited update on the Nissan LEAF battery replacement plan.
...

These replacement batteries are the same battery found in 2015 LEAF vehicles, which are also on sale now at Nissan dealers. As a replacement, this battery is expected to provide similar range and charging characteristics as the battery offered since the launch of the LEAF in 2010. Changes in battery chemistry, however, have been made in an effort to make the battery more durable in extremely hot climates. (So, yes…this is what you’ve been calling the “lizard” battery.) We knew it was important to early buyers to purchase the latest technology. Holding the replacement program until this summer meant we would be offering just that.

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http://www.mynissanleaf.com/viewtopic.php?t=23145 is a thread I found discussing '14 Leafs and what battery is included. I'm sure there are others.

As I read the quote it says - the packs being offer for sale as replacements are the same as the packs in the 2015 Leafs. Didn't say there aren't 2014's with the pack.

But once again, I am only exploring why my higher mileage car is doing well. The best answer to fit so far is "more frequent battery cycling and higher mileage" is good for the battery. The real test will be the 6 year and 100K mile threshold.

One thing I notice is that when I'm down to <20%, the GIDs do seem to drop more quickly.
Also, I had a "battery software" update done after the first yearly battery check. The Nissan app was telling me I needed 10-20 mins of charging after showing that a charge to 100% had finished. The update fixed it. Any one else had this happen?

Next time I use the car I'll update my signature with the latest spec reported by LeafSpy

http://www.mynissanleaf.com/viewtopic.php?t=23145 is a thread I found discussing '14 Leafs and what battery is included. I'm sure there are others.[/quote]

Thanks, but yes I was part of that discussion.

IBeLeaf2 said:

As I read the quote it says - the packs being offer for sale as replacements are the same as the packs in the 2015 Leafs. Didn't say there aren't 2014's with the pack.

But once again, I am only exploring why my higher mileage car is doing well. The best answer to fit so far is "more frequent battery cycling and higher mileage" is good for the battery. The real test will be the 6 year and 100K mile threshold.

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How about an unrelated question? Do you think that cell balancing happens all the time or only when traction pack is engaged? either running or charging?

If its the latter, then the pack would have a greater balance which means a greater equalization of work across the cells. This in itself would increase the pack longevity.

Now for some this might seem like small steps, too small really and they would be correct, initially. But what happens is the lower cells receive a larger part of the load which creates greater voltage swings increasing degradation. This imbalance adds up over time and if there is insufficient time for balancing to happen this is the issue we get. a pack with 95% of the cells at nearly 100% of their capacity and a small handful that are now at 75% of their capacity but still more than enough to destroy the range.

IBeLeaf2 said:

I wasn't doing much wishful thinking, just trying to determine why my battery is doing so well compared to others who have lost bars.

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Are the others you are comparing yourself to also in Maine? With an average high of 79 in July (highest month) I don't expect you would have any significant battery degradation issues, regardless of whether your battery is original or 'lizard' chemistry.

Aussie said:

IBeLeaf2 said:

I wasn't doing much wishful thinking, just trying to determine why my battery is doing so well compared to others who have lost bars.

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Are the others you are comparing yourself to also in Maine? With an average high of 79 in July (highest month) I don't expect you would have any significant battery degradation issues, regardless of whether your battery is original or 'lizard' chemistry.

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I don't recall a summer that hasn't had days in the 90's. Maine is a big state, Presque Isle still has 4' of snow on the ground, Kittery has daffodils up. But don't tell anyone it, isn't tourist season and the restaurants aren't open yet.

If it is true that heat is the only reason batteries degrade, than let's spread that fact around. I see too many posts about battery degradation and not enough indicating it is only heat related. I've had people say to me that they won't buy an EV because the "car/battery wears out to fast" and "they aren't suited for the Maine climate"

I've also read on My Nissan Leaf things like "never charge to 100%", "never leave it at 100%", "charge just before you need it, not when you are done using it", "quick chargers are bad for the battery" and other warnings. I do all of those bad things and still the battery is doing well.
Are we giving EV's a bad name? Or justifiably warning potential buyers to avoid the pitfalls.

Or perhaps there have been other upgrades to battery chemistry before the "lizard" that explain why I get away with breaking the rules. Although my car is not expose to temps over 100F, that is due to where I live not because I avoid them.

I understand we are more apt to hear about the problems than the positives. But if it is only heat that causes the problems let's say so and stop worrying potential EV buyers who live in the more habitable sections of the country.

There are other contributors who live in the cooler climes. Seems likely LeftieBiker could chime in here.

If it is true that heat is the only reason batteries degrade, than let's spread that fact around. I see too many posts about battery degradation and not enough indicating it is only heat related. I've had people say to me that they won't buy an EV because the "car/battery wears out to fast" and "they aren't suited for the Maine climate"

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The older battery chemistry, used before April of 2013, degrades over time as well as with heat. The only exception to this seems to be in very cool (cooler than Maine) climates where it pretty much never gets really hot. As for breaking "rules" about never letting the car sit at 100%, that also depends on the pack temp. Do you leave it at 100% for days in 90F weather? And there is no "rule" against charging to 100% - only one about not leaving it there for more than a few hours, especially in hot weather. And QC is only "bad for the battery" to the extent that it generates heat: if the pack is already hot, then QC is bad. If the pack isn't hot, then QC is fine.

LeftieBiker said:

If it is true that heat is the only reason batteries degrade, than let's spread that fact around. I see too many posts about battery degradation and not enough indicating it is only heat related. I've had people say to me that they won't buy an EV because the "car/battery wears out to fast" and "they aren't suited for the Maine climate"

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The older battery chemistry, used before April of 2013, degrades over time as well as with heat. <snip>

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All batteries degrade due to time, heat and charge/discharge cycles. The different chemistries do so at different rates in each category, but they all do so.

As for Maine, the occasional 90-deg day is very different from constant ones, where overnight ambient temps rarely drop below the '70s ('80s in places like Phoenix) for months at a time. So, heat matters, but sustained higher temps which prevent the battery from cooling down much are also critical. So, I wouldn't expect a car in Maine to show as much degradation as an area which sees similar high temps, but for a longer period of time and without large overnight temperature deltas.