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. -- View this message in context: http://electric-vehicle-discussion-list.413529.n4.nabble.com/To-fully-charge-or-not-to-fully-charge-that-is-the-question-tp4683954p4683958.html Sent from the Electric Vehicle Discussion List mailing list archive at Nabble.com. _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org Read EVAngel's EV News at http://evdl.org/evln/ Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA)