Lithium metal reacts violently with water to produce LiOH and H2. Lithium ions embedded in something else (a polymer electrolyte for LiPo cells) produce the sam

Lithium metal reacts violently with water to produce LiOH and H2. Lithium ions embedded in something else (a polymer electrolyte for LiPo cells) produce the same products, but at a significantly reduced rate so the reaction can be cooled below its critical temperature. We don't use lithium metal in EV cells (they also tend not to be rechargeable). https://en.wikipedia.org/wiki/Lithium_metal_battery https://en.wikipedia.org/wiki/Lithium_metal_battery https://en.wikipedia.org/wiki/Lithium-ion_battery https://en.wikipedia.org/wiki/Lithium-ion_battery