Diogeneyve

Hi @John, @PurePower, @Youda  , I had a third visit to site and managed to non-intrusively gain access to the inside the battery box . The image below of BMS refers.

I measured negative 50V at points 1,2.3,5 and 6. Nothing at 7.    I deducted the following simplified schematic as seen below :
EDIT : please note that the orientation of my CFET is wrong , it should be mirrored horizontally:

The readings inferred that both  CFET (ChargeMOSfet) and DFET (DischargeMOSfet)  had been turned on (there was no forward voltage drops from the body diodes inside the mosfets). Please note that the components are actually duplicated in parallel , eg. there are 8 cfets,8dfets,8 sets of fuses.
There was no reading on 7 , which inferred the second fuse array had blown. This is an interesting fuse in that it has 4 pins instead of 2. You can note that in the image as well. Turns out  this is a very interesting fuse  , some of you might be familiar with it , but me , never knew it even existed. Following is a link from a helpful guy that identified the fuse type and explained the working and meaning of it.
 
http://www.karosium.com/2016/09/the-weird-fuses-in-laptop-batteries.html?m=1
 
I will continue this post in a next post.