CATL debuted its 9 MWh TENER Stack at Smarter E South America 2025, the world's first stackable, containerized energy storage system offering 45% less land use, 50% more energy density and five years of zero degradation. . Landmark innovation pairs high capacity with flexible transport, redefining large-scale energy storage MUNICH, May 7, 2025 /PRNewswire/ -- CATL today unveiled the TENER Stack, the world's first 9MWh ultra-large capacity energy storage system solution set for mass production at ees Europe 2025. . The world's biggest battery maker unveiled its latest utility-scale battery energy storage product- the Tener Stack – at the Smarter E show. The company revealed the next-gen product at ees Europe 2025.