with nylon straps bolted to the floor of the van. quite impossible to move.
Actually no. Although this set of cells was recently plugged into the system. So it had about a week of charging/discharging with not a lot of driving. (currently at home, not traveling)
Ok, with this I would totally agree. They were not. That might be one of the reasons. maybe? Still hope it is a defective cell and a seller which is gone from the face of the earth.
Black tape was there to secure the cells before the silicone glue started to work. One part of the black tape was also to insulate the connections And yes, better separation. Although, the problem happened inside one cell. the others look intact, but still not planning on using them further, as per the dubious seller.
As I said, I was there, it all happened in seconds. After seeing the flame and extinguishing was 5 seconds. And it began slow. I learned that LiFePo4 fire is not the same as standard Li-ion (cobalt)