Assuming that Boeing is able to sell the concept of a fire proof/heat proof containment and overboard discharge of effluents for the Lixx batteries, I wonder how long the airlines will be able to stand what was already an apparently abnormally high battery replacement rate prior to the fire/overheats. These batteries cannot be cheap and moving them to outstations may be a problem. Are you going to be able to carry a COMAT shipment of a Lixx battery on a passenger airplane?
From the maintenance aspect, changing a NiCad battery on a turnaround was only a grunt job, opening a sealed battery container and possibly finding the contents fried will probably cause some delay.
The maintenance shop where they maintain the Lixx batteries will certainly be a more interesting place too. Maintaining NiCads is a pretty demanding chore what with the necessity for depleting them completely and then charging and making sure the cells are balanced. Having cells that may erupt should keep the techies on their toes.
I also wonder if all the weight involved in the containment and venting systems plus the extra monitoring systems, etc, hasn't wiped out the theoretical weight saving of going to this new technology?