> You cannot heat the iron around the cell or in the call walls up to 543°C with electric heaters inside the cell. They would have to reach much higher temperatures than any electric heater is capable of.
It wouldn't have to be uniformly heated to 543 C and couldn't uniformly remain at that temperature anyway. It would just have to be the average temperature in order to store the required energy. And there are electric heaters that reach well above 1.200 C.
