researchers said the growth of metal fibres, called dendrites, could cause short circuits.
ISTR that this is precisely the same reason NiCad's die.....the charge/discharge cycles cause these Dendrites to grow, eventually puncturing the plate-seperator and short-circuiting the cell internally.. they can sometimes be destroyed (the Dendrites!) by a momentary large over-voltage/high-current (connect a 12V lead-acid to a single NiCad cell) which vapourises the Dendrite . Unfortunately, the insulating seperator is still compromised and the" fix" is only temporary.
There is, to the best of my knowledge, NO way to stop the thermal runaway in a Lithium cell , once it has started....containment is the only option.
(though Boeing "could" redesign the racking etc, so the fireball simply burns it's way down through the bottom of the fuselage and drops to the ground/sea/town 30,000 feet below/school/church/hospital....no, it would have to "plummet" then
Given the relatively large size and large energy-storage in the 787 application, the difficulty of seperating cells and individually "sandbagging" them is totally impractical.....older, proven technologies are the safest option.