I don't understand why safety should depend on architecture and...

I don't understand why safety should depend on architecture and not chemistry.

My information depended in part on the recent article:

Rudola, A., Sayers, R., Wright, C.J. et al. Opportunities for moderate-range electric vehicles using sustainable sodium-ion batteries. Nat Energy 8, 215–218 (2023).

I fear this article in the scientific journal Nature, though in the public domain, is behind a pay wall or accessible in a subscribing library. Emphasis in quotes is mine.

Note that Na-ion stands for Sodium ion and Li-ion for lithium ion.

"Aside from excellent in-operation safety characteristics for theNa-ion technology in general, inclusive of both robust abuse toleranceand high thermal stabilities . . ."

"Cu can oxidize, resulting in disastrous consequences, if aLi-ion cell is ‘overdischarged’ close to 0 V. This is the reason why suchLi-ion cells are actually between 2–2.8 V at their rated 0% SOC, thus,obviously not at ‘zero energy’. It is also why international regulations stipulate that all such commercially-available Li-ion cells are to be transported at ~30% SOC, incurring cost and decreasing the safety of such partially-charged cells.Na-ion cells are also inherently resistant to ‘overdischarge’ conditions (for Na-ion, overdischarge would be negative voltages). As explained previously, this overdischarge resistance will be important in packs, where several cells are connected in series: if some Na-ion cellsin the series string slip to overdischarge conditions, the result will not nearly be as hazardous as the analogous situation seen in Li-ion seriesstrings."

"The same working principle and manufacturing methodology for Na-ion and Li-ion batteries mean that Na-ion batteries are a drop-in replacement in any Li-ion battery manufacturing plant in existence currently."

In other words, the architecture of a Na-ion battery can be such that, though chemically different, it could simply be slipped in to the holder of a Li-ion battery in a vehicle factory.