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2 YEAR UPDATE !!
Hello everyone...
Just a quick update after 2 years of almost daily use commuting to work (5 miles round trip)...
Attachment 8739
After 90 charge-discharge cycles and 2500 miles...
The delta between highest and lowest cells is only 0.031 volt at the bottom and 0.055 v at the top fresh off the charger.
I only had 2 minor problems since the last update, one of which was a real head scratcher. Intermittent electronic problems are a real PITA to locate!!
The first problem was about 6 months ago.
I noticed that my temp sensor on the negative terminal of the battery pack was getting abnormally hot during charging.
Attachment 8740
It usually never gets over 76-78 degrees F during the entire charge cycle. But for some reason I started to see temps in the upper 90's

I had to disassemble my left side battery box to re-tighten the negative cable terminal that had vibrated loose. It was barely loose, but I guess just enough to cause the heating issue. I never had any issue with the bike not running well.
It's definitely a good idea to strategically position some temp sensors at different locations in your battery pack!!
The second, very recent problem was that my headlights kept turning off on my ride home at midnight. This was completely intermittent, unrepeatable, and self correcting. I tried wiggling wires and harness connections, sometimes making the lights go off/on, or no effect at all. I re-wired the headlight harness, rebuilt the connectors and rechecked the entire 12 v circuit as well as the 100v side. The problem persisted even after going through all of the wiring with a fine toothed comb (and my multimeter)

I think the Sevcon DC-DC converter has an intermittent problem. The printing on the device states 80v to 13.4v .... So maybe it doesn't like the 20v overvoltage of my battery pack

I replaced it with a much lighter and smaller Vicor and have since had no more headlight issues
Attachment 8741
I suspect that these cells will easily last me a few more years until better batteries come our way

Ciao!! "