The first CO2 battery for storing long-term renewable energy was launched in Sardinia, Italy and is integrable with solar and wind farms.
The principle that Energy Dome is using is that CO2 is extracted from a dome in which it exists in gaseous form and is compressed in a huge tank, under pressure and at room temperature. Once compressed, the gas turns into a liquid. In order to generate electricity, the liquid CO2 is heated and transformed again into a gas that feeds a turbine to generates electricity. CO2 is at no risk to leave the closed container which is built of steel, CO2 and water, so no need for expensive or rare metals like cobalt or lithium.