The ECO STOR Storage Monitor displays the development of large-scale battery storage capacities in Germany based on publicly available data from the Market Master Data Register. ECO STOR thus creates transparency and clearly demonstrates the strong growth in the German storage market. The analysis includes all battery storage systems (technology-neutral) reported in the Market Master Data Register with a storage capacity greater than 1 MW and not connected at the low-voltage grid level. Projects in the planning phase are not subject to reporting requirements, so it can be assumed that the actual scope of planned projects is larger than what is presented.