Without repeating well-documented details, the lessons the NTSB hearings about li-ion in transportation have quite a bit to say about cell format as well as chemistry. If anyone is interested I can upload the entire hearings. During the hearings, which I attended on bahalf of an aviation client, testimony from Tesla, the US Navy (submarine batteries), numerous manufacturers and technical experts was presented. There were a handful of generalizations which were, for me anyway, unforgettable:
1) RAID is a sound principal, but in the battery case, failure containment and individual cell quality control are NOT RAIDable!
Tesla, for example, tests every single cell both in production and prior to installation then maintains continuing records of each cell performance. (This was discussed at some length during the hearings).
2) Other things remaining equal the larger the format the higher the catastrophic failure risk due to the problems maintaining smooth cell chemistry changes, barrier stability and failure protection as cell size increases. Further, the more nearly spherical the cell design the easier smooth cell performance can be.
3) The quality control process in EV and other transportation use needs to exceed anything traditionally known with lead-acid, in-card or other older chemistries.
4) Seemingly riskier chemistries can be deployed safely if steps 1 and 2 are fanatically adhered in all aspects of deployment.
Boeing ignored those first two steps in initial B787 li-ion deployment, as did the US Navy in submarines. The Navy learned. Boeing refused to deal with the format issue, so developed a massively separate failure containment process for the B787 main batteries, soon following the hearings.
Regardless of what new technology might emerge we can rely on Tesla to be the industry safety issue. Candidly, I ordered my own Model S soon after returning from these hearings. Tesla probably will continue to be the industry leader in new battery technology, but it certainly will be the leader in battery safety.