What about the opposite ie the car structure should be the battery! Carbon Fibre can be a very effective Anode at double the strength of steel - not v effective

What about the opposite ie the car structure should be the battery! Carbon Fibre can be a very effective Anode at double the strength of steel - not v effective at it’s max strength of 10x Steel. Not as energy dense as curent Tesla batteries, but at the system level, should in theory save 50% of weight for same capacity, which is huge! Also lower energy density is naturaly safer, ie less likely to go up in flames. Just guessing, but this might partly explain how the Tesla Semi Truck is getting the claimed 500 mile range, that most commentators say is impossible?