The energy storage system combines lithium- and sodium-ion batteries to supply 270,000 households with 98% renewable electricity throughout the year. It is the first such hybrid battery project set into operation at grid level.https://www.notebookcheck.net/First-mixed-sodium-ion-battery-station-at-grid-level-used-to-balance-wind-and-solar-energy-peaks.1025822.0.html
Impressive. But what benefits do lithium batteries bring to this installation? It should only be the rate of charge. But that can be mitigated simply employing more Na batteries. Unless they sized the whole installation right up to the theoretical max input capacity.