Carex has an interesting approach to creating a bench-scale "zinc/ iodine" secondary cell using sand to absorb the formed molecular iodine:
I tried using "halloysite clay" ( kaolin family). which is known to be microtubular and should absorb iodine well. It does. Of course, with a bench-scale prototype, we do not want iodine escaping into the air.
I am reaching 1.36 V with charging at 3 V/ 100 mA for 3-4 minutes. Ashirt circuit sees the cell quickly rebound, a good sign.
My students will build these cells, obtain real-time acquisition and we will post our findings. We will use grafoil electrodes, activated carbon, zeolites, etc. Try different sands and even grout cement!
Follow the teachings and example of the great Michael Faraday! Young minds will make their way to "energy-storage" and "AI". Ise Google's "bard" daily to help me organize my research thoughts.
Involvement is the key to future success.