CATL has unveiled the TENER Stack, the world’s first 9MWh ultra-large capacity energy storage system solution set for mass production at ees Europe 2025, representing a strategic leap forward in capacity, deployment flexibility, safety, and transportability.
In response to fast-growing global energy demands, from AI-driven data centres to industrial electrification, TENER Stack is engineered to help utilities, developers, and industrial users unlock greater economic value from every square metre of installation.
“CATL has always been at the forefront of the energy transition,” said Amanda Xu, CTO ESS & President of ESS Europe CATL. “To meet the expectation of a BESS system that has high energy density, small footprint, simpler AC-side configuration, and flexible deployment, we bring the latest CATL TENER energy storage solution. It breaks the limitations of power capacity and product transportation, and makes breakthroughs in space utilization, energy efficiency, and cost.”
Breakthrough Capacity And AC-Side Compatibility
TENER Stack incorporates CATL’s high-energy-density cells with five-year zero degradation technology, achieving a 45% improvement in volume utilisation and a 50% increase in projected energy density compared to conventional 20-foot container systems. The internal capacity reaches up to 9MWh, which is adequate to charge 150 electric cars or power an average German household for six years.
To enhance compatibility and system efficiency, TENER Stack supports both centralised and string PCS (Power Conversion System) architectures. This dual-technology path ensures seamless integration with mainstream AC-side equipment and a wider array of grid applications.
The superior space efficiency of TENER Stack delivers significant economic value. For instance, deploying 800 MWh of storage using TENER Stack requires nearly one-third fewer containers than traditional 6 MWh systems. This reduces the number of PCS units and hidden costs associated with system oversizing and increases land-use efficiency by 40%. Overall, developers can expect up to 20% optimisation in total station construction costs.
Transport Without Compromise
In response to logistical challenges associated with transporting containers exceeding 36 tonnes, the legal threshold in many countries, CATL has developed the “two in one” design. Each half-height unit is strictly controlled under 36 tonnes, ensuring compliance with transport regulations across 99% of global markets.
This innovative split design allows for standard shipping methods, including standard container spreaders and liners, significantly reducing waiting times and specialised transport costs by up to 35%. With a lower centre of gravity and flexibility for height-restricted routes, TENER Stack can easily adapt to unique transport scenarios such as bridges and rural areas, highlighting the advantages of its innovative structural design.
Advanced Safety Standards and Thermal Management
With fire safety under global scrutiny, TENER Stack leverages CATL’s robust LFP battery chemistry, known for its inherent thermal stability. Upgraded gas sensors offer 40% higher sensitivity, triggering suppression systems 35% faster. A new triple-layer insulation design boosts fire resistance to two hours and the system meets IEEE693 seismic standards, enduring magnitude 9 earthquakes and Category 5 hurricanes.
Additionally, an overhead TMS (Thermal Management System) design reduces thermal radiation, cuts land and maintenance costs, and keeps noise to 65dB(A) at one metre which is ideal for urban use.
Not Just Batteries, But an Energy Vision
By the end of November 2024, CATL’s ESS products were deployed in over 1,700 projects across the world, spanning all climate zones and operating environments. In 2023, recognizing the evolving and changing needs of the customers, CATL unveiled TENER, a twenty-foot equivalent unit (TEU) containerized energy storage system with 5-year zero degradation technology, and TENER FLEX, a rack energy storage system for flexible deployment.
TENER Stack builds on the proven performance of CATL’s TENER and TENER FLEX series, combining the benefits of previous models with new levels of capacity and transportability. With TENER Stack, CATL reinforces its commitment to helping global partners accelerate the energy transition, delivering more power in less space, safely and sustainably.
“TENER Stack, giant, flexible, reliable and quiet. We are not only delivering an energy storage product, but a solution for energy accessibility that can be applied globally,” said Hank Zhao, CTO of ESS Europe CATL. “9 MWh is not the limit of the energy capacity or space. Every breakthrough in energy density in the future will unleash greater energy value from a smaller footprint.”
