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> There are still orders of magnitude between current batteries and the theoretical hard cap.

Not at all. Existing cathode materials have a theoretical coulombic capacity of about 200 mAh/g (mostly less than this value, a few more have more). So for a 45g cell like an 18650, you are looking at 9,000 mAh maximum in the impossible world where your battery is 100% cathode, no anode or electrolyte. Those cells are already > 3000 mAh, so there is no way there are orders of magnitude between current batteries and the hard cap.

On the contrary, for contemplated chemistries the practical hard cap is probably less than 2x current capacity/weight values (since you need a significant amount of anode and electrolyte in practice), and almost certainly less than 3x.

> Current batteries throw away enormous capacity due to the safety constraints in preventing thermal events.

If by "current batteries" you mean current chemistries like Li-ion and existing and contemplated cathode materials, then this is not correct. The batteries have essentially the ideal material ratios within the existing manufacturing capability. That is, if you were willing to have a much less safe battery with the same materials you would gain almost no capacity. The main concession to safety is when a safer cathode material is chosen, like LiFePo over cobalt or whatever.



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