Are you sure the 2013 cells were the same chemistry? I thought they were the
older spinel type, not NMC.
Anyway, worst case for decreasing cell life is high voltage and high
temperature as shown by Dahn and other researchers, so most manufacturers
recommend not charging to 100% SoC regularly. I have > 50k on my LiFePO4
cells with no noticeable capacity loss, but I usually only add as much
charge as I will need for the next couple days, only charging to 100% a few
times per month for longer trips. Something not usually mentioned is
increase in internal resistance.  I think this is creeping up in my cells,
as temperature rise seems a bit more than it used to be, but I have not
quantified it. This is a by product of capacity loss due to deposition on
the electrode SEI layer as result of electrolyte degradation.  If ir becomes
too large, the resultant added cell heating could push them up to higher
temperatures in hot summer months accelerating degradation, further
increasing ir, resulting in more degradation...hasn't been a problem so far,
cells usually are below 98F on hot summer days. LiFePO4 has less problem
with electrolyte degradation compared to other higher specific energy
chemistries such as NMC due to the lower cell voltage.

I usually don't plug in my laptop either. Only when it gets down to around
40%SoC or so, for the same reason. Killed the battery in my older one within
3 years by leaving it plugged in all the time. My work laptop which I only
occasionally plug in still has almost full battery capacity after 5 years.

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