The steel box is a
PR disaster as well as a maintenance headache with its 52 bolts holding the lid on.
The changes in the cell manufacturing process, battery construction that includes ceramic heat shielding, new internal battery electronics and logic and a revised battery charger are the actual fix. The battery is a completely new design, but the containment box ensures that the travelling public - and many uninformed aircrew - will continue to regard the B787 battery as a highly dangerous piece of equipment. (Which the original, in fact, was)