It's kind of different though, molten salt "batteries" before this were really thermal storage, while this is regular old chemical storage. That means no moving parts, just sit it in place and use it like any other chemical battery.

The downside compared to most other batteries though is that the operating temperature is hundreds of degrees. The batteries need to be "thawed" before use, and if they ever freeze (which they will if they aren't used, they are insulated but still need to use the waste heat from charging/discharging cycles) they need to be thawed again. You can do this just by running power through them, but it takes a lot of energy.

These could be legitimately groundbreaking for 24 hour cycling if coupled with solar in regions with very few cloudy days, but they can't be used for anything the way lithium can.