On May 7th, 2025, CATL has unveiled the world’s first mass-producible 9MWh ultra-large-capacity energy storage system solution, TENER Stack, setting a new industry benchmark with its groundbreaking technology. This innovation marks another milestone for CATL in the energy storage sector, following the launch of its 6.25MWh Tianheng ESS in 2024. Compared to its predecessor, TENER Stack not only achieves a significant increase in system energy density but also advances transportation efficiency and safety performance, establishing a new technical standard for the industry.
TENER Stack 9MWh Energy Storage System
Capacity Breakthrough: 20% Reduction in Overall Station Costs
TENER Stack utilizes CATL’s high-energy-density cells, featuring zero degradation over five years. Compared to traditional 20-foot container systems, TENER Stack improves volume utilization by 45% and energy density by 50%, with a single-unit capacity of 9MWh.
The system’s large capacity also delivers substantial economic benefits. Deploying 800MWh of storage capacity with TENER Stack reduces the number of containers required by nearly one-third compared to traditional 6MWh systems, while increasing land-use efficiency by 40%, ultimately cutting total station construction costs by 20%.
Breaking Transportation Limits: Compliant with 99% of Global Market Regulations
To meet the 36-ton road transport weight limits in many countries, CATL developed a "Two in One" modular design, keeping each half-height container’s weight strictly below 36 tons—ensuring compliance with 99% of global transport regulations.
Additionally, its innovative split design adapts to multiple standard transport methods, reducing wait times and cutting special transport costs by 35%. With a lower center of gravity and enhanced flexibility, TENER Stack can easily navigate bridges, rural roads, and other challenging transport scenarios, showcasing its structural advantages.
Upgraded Safety Standards: 2-Hour Fire Resistance
As safety becomes increasingly critical for energy storage plants, TENER Stack enhances gas sensor sensitivity by 40%, improving suppression system response speed by 35%.
Furthermore, its new 3-layer insulation design extends fire resistance to 2 hours, while the system complies with IEEE693 seismic standards, withstanding magnitude-9 earthquakes and Category-5 hurricanes.
Strong Performance in Energy Storage Business
According to the China Energy Storage Alliance (CNESA), CATL ranked No.1 globally in energy storage battery shipments in 2024. The company’s energy storage battery revenue reached 57.3 billion yuan, accounting for 15.83% of total revenue, with a gross margin of 26.84%—up 8.19% YoY and surpassing its power battery business margin (23.94%), solidifying energy storage as CATL’s second growth driver.
6~9MWh Energy Storage Systems: Who Will Lead the Future?
As market demand evolves, large-capacity energy storage systems continue to advance. In 2024, 20-foot 5MWh+ systems were widely released and commercialized in H2. By 2025, 6~9MWh+ systems took center stage at ESIE 2025.
Leading companies, including CRRC Zhuzhou Institute, CATL, BYD Energy Storage, Hithium, EVE Energy, CALB, Cornex, Narada Power, Sunwoda, REPT, CEEG, NR Electric, Resource Electric, Goldwind, TBEA, Ganfeng Lithium, Bull Electric, Higee Energy, and JinkoSolar, have all entered the 6MWh+ large-capacity storage market, making it the next-gen commercialization focus.
CRRC Zhuzhou Institute: New 6.X battery cabin (6.9MWh), mass production in Q4 2025.
Hithium: ∞Power 6.25MWh 2h system, featuring ∞ Cell 587Ah battery, mass production in H2 2025.
EVE Energy: Next-gen 6.9MWh system, CTP-integrated design, 20% higher energy density per unit area.
CALB: 6.25MWh liquid-cooled container, 2-in-1 HV design, 14.9% smaller footprint.
Cornex: Upgraded CORNEX M6 DC prefab solution (6.28MWh & 6.91MWh variants).
Narada Power: Center L Ultra 6.25MWh system, "AC/DC integrated" design, for 2-8h scenarios.
REPT: 6.26MWh system, 12,000+ cycles, 20-year lifespan.
Sunwoda: 6720kWh liquid-cooled container.
Further breakthroughs in 7MWh+ systems:
ZTT: "ENERGRID NA7" 7.58MWh liquid-cooled system (2000V DC, AC/DC integrated).
Gotion High-Tech: 7MWh battery cabin, with AI analytics, smart thermal control, and 3D protection.
8MWh+ systems entering the market:
HyperStrong, Envision Energy, Narada Power, Lishen Battery have launched 8MWh+ solutions
Narada Power: 8.338MWh system, self-developed solid-state battery, enhancing capacity & safety.
Envision Energy: 8MWh+ EN 8 Pro, world’s first AI-empowered ESS, lowering LCOE.
AC New Energy has introduced a 9MWh+ energy storage system, pushing boundaries further.