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[DonTom]

How are the cells ever going to balance?

Do a balance charge every other month or so.

And why does Energica say right on the screen to let it finish charging when you're at ~80% SOC?

Clearly you haven't read it. It's pure Google Translate Italian. I can't remember the exact wording off the top of my head but it's something like, "In order to enable balance sequence it is suggested to do not disconnect..."

How it *should* read is more along the lines of, "If you would like the batteries to balance, we suggest you do not disconnect..."

It's more like "It is suggested to NOT disconnect until charge is completed". Next time I see it, I will write down the exact words. FWIW, I usually disconnect at around 90% SOC to make sure I can make it to Reno from Cisco Grove or vice versa. 80% will cause some range anxiety, but I would most likely make it, but I can ride faster with no worries at 90% SOC (11.7 KWH battery).


I assume my new Experica with the 22KWH battery can make the 99.0-mile hilly trip on a home charge as long as I don't go too fast.



-Don-  Reno, NV

[DerKrawallkeks]

Don't store it full or empty in a hot environment, as this accelerates degradation.

What is your source for accelerated degradation when empty?
From all I know, this is wrong.

[DerKrawallkeks]

Loose rule of thumb is that with 0-100% charge cycles (no pauses) you'll be lucky to get 100 cycles out of the battery.

What is your source for this? This seems very wrong.
Also what is your source on "no pauses" having an influence?

[MVetter]

What is your source for accelerated degradation when empty?
From all I know, this is wrong.

This is what I was told explicitly by Luke Workman, a friend who is one of the brightest minds in the battery world today. He also was responsible for redesigning Zero's 2012 packs to not catch on fire. Now he and his equally brilliant wife, Erika, run a battery consulting and recycling business. https://www.electricgoddess.co/

I'm paraphrasing but Luke said something along the lines of, "one of the worst possible things you can do is leave a battery empty in a hot environment. It rapidly increases growth of dendrites and will cause irreparable damage."

[T.S. Zarathustra]

Loose rule of thumb is that with 0-100% charge cycles (no pauses) you'll be lucky to get 100 cycles out of the battery.

What is your source for this? This seems very wrong.
Also what is your source on "no pauses" having an influence?

Four years of studying electrical engineering at RIT.
What is your source?  If you want to study batteries I can recommend Linden's Handbook of Batteries, by David Linden and Thomas Reddy.
Edit. Here is a link. https://www.amazon.com/Lindens-Handbook-Batteries-Fifth-Kirby-dp-1260115925/dp/1260115925/ref=dp_ob_title_bk

[DerKrawallkeks]

@MVetter
That surprises me, cause both "Degradation Mechanisms in NMC-Based Lithium-Ion Batteries" figure 23 and "Aging of Lithium-Ion Batteries in Electric Vehicles" figure 28 show that a low SOC is beneficial for storing batteries.
I was not able to find any study that got different results.

@T.S. Zarathustra I was not able to find where it says anything about the rule of thumb of 100 cycles at 100% DOD in Lindens Handbook of Batteries.
Where is that rule of thumb described?
This would be a very low number of cycles for todays batteries.

[T.S. Zarathustra]

@MVetter
That surprises me, cause both "Degradation Mechanisms in NMC-Based Lithium-Ion Batteries" figure 23 and "Aging of Lithium-Ion Batteries in Electric Vehicles" figure 28 show that a low SOC is beneficial for storing batteries.
I was not able to find any study that got different results.

@T.S. Zarathustra I was not able to find where it says anything about the rule of thumb of 100 cycles at 100% DOD in Lindens Handbook of Batteries.
Where is that rule of thumb described?
This would be a very low number of cycles for todays batteries.

It took you less than 2 hours to read through all ~1400 pages. Wow, I'm impressed. Are you in the Matrix?
Why would you think that a specific rule of thumb was in a book. Rule of thumb, by definition, is not in books.
I said that exact number depends on the exact chemistry, and that this is a good book if you want to learn about batteries.
Since you have the book you can read (starting on page 51 in my copy) all the details about "Mass transport to the electrode surface" (formation of dendrites) and Fick’s second law of diffusion.
I'm not familiar with the "DOD" acronym. Do you mean State Of Discharge?

[DerKrawallkeks]

DOD is depth of discharge.
I just want to point out that 100 cycles at 100% DOD is very very far from any cell that is used in any EV. This is less cycle life than even the most extreme high-power cells provide.
I want to stop the spread of misinformation.

[MVetter]

I never said low SoC. I said “empty in a hot environment.”

[DerKrawallkeks]

Empty = low SOC.
"Aging of Lithium-Ion Batteries in Electric Vehicles" figure 28 clearly shows the lower the SOC, the better for storage, both in hot and cold conditions.
Ideal storage SOC at high temperature would be empty.

[T.S. Zarathustra]

"the effect of storage is more pronounced not only with high storage temperatures and long storage periods," Page 73. Linden's Handbook of Batteries, by David Linden and Thomas Reddy.
I want to stop the spread of misinformation.

Edit. Here is information from a Samsung SDI datasheet for one of their Lithium Ion batteries, INR18650-25R.
"Storage temperature
(Recovery 90% after storage)
1.5 year -30~25?(1*)
3 months -30~45?(1*)
1 month -30~60?(1*)"
"Note (1): If the cell is kept as ex-factory status (50±5% SOC, 25?),"

To translate.
The manufacturer delivers the batteries with 50% charge, plus or minus 5%.
If batteries are kept between -30° to 25° Celsius they can be stored for up to 1,5 years.
If batteries are kept between -30° to 60° Celsius they can be stored for up to 1 month.

[DerKrawallkeks]

Almost all batteries are delivered at roughly 50% SOC. This is to make it possible for them to be stored without paying attention to their self-discharge, while staying below the central graphite peak (around 55% SOC) above which the aging effect is significantly higher.

As I already stated with sources, an empty battery is still the best for storage.

The quote that you took from the book has nothing to do with the topic. You intentionally cut it short, since it continues "the effect of storage is more pronounced not only with high storage temperatures and long storage periods, but also under more severe conditions of discharge following storage". It then continues to talk about the influence of the discharge load after storage, which is completely unrelated to my original point about low SOC.

This quote only mentiones high temps and long storage as bad influence. That's not a surprise to anyone I think.

So yea.. I don't really know what you are trying to express here.

[wadejesu]

Did someone say there is a 14.4  FXS version in Europe?

[princec]

No, there isn't.

So far all literature I've come across has stated that LiPo batteries should be stored at effectively just under "50% SOC"*. Storage under effective 0% SOC appears to risk eventual short from metal dendrites and potential explosion. The warmer things are the faster dendrites can form. Does anybody disagree with this?

Cas

* Where "50% SOC" is where the manufacturer finds the median voltage between what they decide is maximum and minimum safe ranges which as MVetter has stated before is 3.65V per cell on a Zero.

[T.S. Zarathustra]

As I already stated with sources, an empty battery is still the best for storage.

Empty = low SOC.
"Aging of Lithium-Ion Batteries in Electric Vehicles" figure 28 clearly shows the lower the SOC, the better for storage, both in hot and cold conditions.
Ideal storage SOC at high temperature would be empty.

I cannot find the source you mention. Who is author of "Aging of Lithium-Ion Batteries in Electric Vehicles"? The closest Google finds is a five page document that has no figure 28.