>Ambri’s liquid-metal battery consists of three liquid layers stacked together based on density. The densest, a molten antimony cathode, is on the bottom, the light calcium alloy anode is on top, and the intermediate-density calcium chloride salt electrolyte sits in the middle. “Think of salad oil and vinegar,” Sadoway says, “except here there’s three layers, and they separate because they’re immiscible.”
>During discharge, the calcium anode releases calcium ions that move through the electrolyte to the cathode, where they form a calcium-antimony alloy. The process reverses during charging.
Antimony's melting point is 630°c, Calcium's is 842°c, calcium chloride's is in between. It takes a lot of energy just to keep the battery in a usable state. I wonder how it compares to a molten salt "battery" that runs a steam generator.
Why do you think it takes a lot of energy to keep the battery in a usable state? It’ll take quite a lot of energy to get to that state.. but the energy it takes to keep it there is not just a function of the temperature. It’s a function of how much insulation you have as well. Insulation is cheap and it gets easier/cheaper the bigger you scale it.
Keeping something at hundreds of degrees for a long time without adding energy is not a very hard problem. There are companies that are making seasonal energy storage for colder climates using this very mechanism. Just heat something up in the summer, and extract the heat in winter.
E.g., see Polar Sands thermal battery. They warm sand to 600°C and it can stay hot for months.
>During discharge, the calcium anode releases calcium ions that move through the electrolyte to the cathode, where they form a calcium-antimony alloy. The process reverses during charging.
Antimony's melting point is 630°c, Calcium's is 842°c, calcium chloride's is in between. It takes a lot of energy just to keep the battery in a usable state. I wonder how it compares to a molten salt "battery" that runs a steam generator.