Aqueous zinc-iron batteries are one suggestion, where storage is though the reversible plating and stripping of zinc at the anode.
One of the problems associated with this chemistry (dendrite growth is another) is hydrogen gas generation from parasitic side-reactions that decompose water – which gradually pressurise the cell with an explosive gas, and deplete the electrolyte.
“Researchers have often tried to evade this issue by installing a surface protection layer that minimises the contact area between the metal anode and the electrolyte, according to the Korea Institute of Science and Technology (KIST, pictured). “However, the corrosion of the metal anode and accompanying decomposition of water in the electrolyte is inevitable in most cases.”
