Calendar Aging of Lithium-Ion Batteries

[Matador]

Though I'd share this scientific publication (published March 2016) I found on the web that has some nice graphs about Calendar Life of Lithium Cell Chemistries depending of storage SoC (% state of charge)....



I was wondering what's the best voltage to store my Sony VTC4 (NMC cells) at :

Here's the link : http://jes.ecsdl.org/content/163/9/A1872.full
Or the PDF file : View attachment Lithium cell Calendar life.full.pdf

If anybody else has some scientific peer-reviewed data on various Lithium Chemistries for calendar life, please share/post it in this thread as a reference to be easly found for future uses.


Matador

 

[Sunder]

Great data. The store at 60% below 25*C has been well known for a while now, but this is great confirmation and gives us a view of what we need to sacrifice if we want convenience of storing batteries ready to use.

 

[Wheazel]

Shame they didnt include some lower temps as well in such a comprehensive test.
Pretty sure cold storage will show even better results.

 

[999zip999]

Cold how cold is cold ? What happens if a battery gets frozen ?

 

[Matador]

Shame they didnt include some lower temps as well in such a comprehensive test.
Pretty sure cold storage will show even better results.

Yes, I think a wine cellar 10-15°C has an even more ideal storage temperature, but that's just my guess, not rigourous testing by any means (I'm just extrapolating from the three curves). Freezing might be bad.

Maybe there are some other scientific publications that include cooler storage temperatures in their testings (but we'd probably have to look longer than 10 month to see any significant capacity reductions, one that exeeds the error margins of the tools used to check capacity).

Hence, that's why I created this thread : I dont think there is "one single scientific research paper" that gives the entire whole pictures about aging of lithium cells (what about cooler temps ? What about longer storage periods (like 10 years, 20 years ?) What about other chemistries (Lithium cobalt, Lithium manganese, Lithium titanate, etc.) what about used versus new (0 cycle, 100 cycle, 200, 300 500, 1000, 2000 etc) ?

So if anybody would like to share more knowledge (aka : scientific knowledge as in publications) about lithium-ion batteries Calendar life/aging this is the thread to add more info on that subject !

 

[Wheazel]

It is clear that fridge temps are at the very least better than room temps, and I am not convinced frozen storage is bad.
It is very clear that frozen charging is bad, but storing might be even better than above 0C.

 

[Matador]

It is clear that fridge temps are at the very least better than room temps, and I am not convinced frozen storage is bad.
It is very clear that frozen charging is bad, but storing might be even better than above 0C.

Very interesting indeed.
I guess it's mandatory to let temps rise back to room temperature before using... Not to be used (especially charged) when just pulled out of the freezer...