That looks pretty convincing. Had it ever been dropped / physically abused,
was it a manufacturing defect or what ?. Compared to the size of the bricks,
those batteries look much larger than the elt type. Are they the same type
and chemistry, or for a different application ?. You said transponder and the
elt doesn't transpond.
I guess this must also have been reported to the safety authorities, so what
was their reaction ?...