Both in their pure form do go kaboom in the presence of water yes, but for a start, Lithium is more toxic than sodium. Other than that I’m pretty sure the exact chemical compound used with sodium to make sodium-ion battery ended up safer than Li-ion. They are not using pure sodium ya know like you don’t get kaboom when you put salt (NaCl) in water. However, I do not know the exact compound and processes without reading wiki or asking GPT. More battery wiz perhaps can chip in.
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