Absolutely correct. IIRC teslas (at least older models, not sure about recent ones) use standard 18650 lithium ion cells. Discharging those past a certain volta

Absolutely correct. IIRC teslas (at least older models, not sure about recent ones) use standard 18650 lithium ion cells. Discharging those past a certain voltage (~2.5v?) will permanently damage the cell and is prevented by the battery management subsystem. In theory it is possible to keep driving the car past a "0%" charge, assuming the safety systems could be bypassed, but you would never get the same range/acceleration on subsequent charges. Worst case would need am entirely new battery pack.