The March 7 released materials lab report has considerable detail on the battery covering some points which have been considered open on this form.
It can currently be found at:
http://dms.ntsb.gov/pubdms/search/do...251&mkey=85973
On my browser (firefox), clicking the download button five minutes ago generated an exception, but clicking the view button downloaded the pdf to my browser, from whence I was able to download the full pdf to my disc.
Among other interesting points, the "Description of the battery" section covers in more detail than I've previously seen the temperature monitoring technique, and responses, and other battery management details. Also mentioned are the container material and thickness, cell manufacturing dates and serial numbers, and so on.
All this in addition to considerable additional detailed observations from the event battery itself.
I think the materials lab report may contain more material of interest to participants in this thread than does the interim factual report also released today. However the NTSB server is currently responding very slowly, so some patience or retries may be needed.