I seem to recall from an article I read about this technology a few years ago that it's efficient partly because when the gas is compressed, they are able to store the heat that is produced, and then later use the stored heat for expanding the gas.
That seems important. I wish we knew how. I found an article that did mention the heat was "stored", with no further detail. The animation down on this page suggests it's stored in water somehow: https://energydome.com/co2-battery/
That seems important. I wish we knew how. I found an article that did mention the heat was "stored", with no further detail. The animation down on this page suggests it's stored in water somehow: https://energydome.com/co2-battery/