[SMM Analysis] The Era of 500Ah+: Rapid Iteration of Large Energy Storage Battery Cells

Recently, the field of large energy storage battery cells has seen continuous developments, showcasing rapid industry growth and technological advancements. EVE's 60GWh super energy storage factory's Phase I project was put into operation in Jingmen, Hubei, in December 2024, primarily producing the 628Ah ultra-large capacity battery cell, Mr. Big. This marks the mass production of the industry's first 600Ah+ large-capacity battery cell. The factory, with an investment of 10.8 billion yuan and a designed capacity of 17GWh, achieves an average production speed of 1.5 battery cells per second, completing four full battery packs in one minute and producing over 40 5MWh containers per day. Hithium Energy Storage, based on 587Ah and 1,175Ah battery cells, is expected to globally deliver its 6.25MWh large-capacity energy storage system in Q2 2025. The 688Ah ultra-large capacity battery cell, jointly released by CRRC Zhuzhou Institute and several enterprises, is planned for delivery in 2025. Sungrow's 625Ah large stacked standard battery cell is also expected to be globally delivered in 2025.

In terms of technical routes, large-capacity battery cells generally adopt stacking technology. Currently, 600Ah+ large-capacity energy storage battery cells have commonly shifted from the 71,773 prismatic size to a thinner "blade shape," with manufacturing processes collectively transitioning to stacking technology. Compared to the winding process, stacking technology has a natural compatibility with large-capacity energy storage battery cells, sparking greater advantages in both economic efficiency and safety. Economically, stacked batteries avoid the C-corner issue during pole piece packaging, fully utilizing the casing's corner space to enhance volumetric and gravimetric energy density, which helps reduce the footprint and civil construction costs of energy storage systems. In terms of safety, as capacity increases, battery cell heat dissipation becomes more challenging, and uneven heat distribution becomes more pronounced, increasing the risk of thermal runaway. However, in the blade shape, the thinner battery cells with a larger specific surface area facilitate heat dissipation, reduce temperature rise, and significantly enhance the safety of energy storage battery cells.

Although stacking technology is increasingly favored in large-capacity battery cells, the winding process still has its unique application scenarios and advantages. For instance, CATL's 587Ah battery cell adopts the winding process. Based on predictions of future energy storage battery cell development trends and considerations for optimal efficiency when integrated into a 20-foot standard container, the winding process was chosen. The specification size no longer follows the "71,173" size of the 314Ah battery cell but instead innovatively adopts a larger size specification, achieving an energy density of 430Wh/L.

With the significant acceleration of the global energy transition, the installed capacity of renewable energy continues to rise, driving a sharp increase in demand for efficient energy storage technologies. Looking ahead, the energy storage battery cell industry is expected to experience even more rapid and robust development. Specifically, energy storage battery cell technology is advancing toward large capacity and low cost, heralding the arrival of the 500Ah+ battery cell era. A progressively improved policy framework is accelerating the industry's standardization and scaling. International cooperation is deepening, and energy storage battery cell enterprises are accelerating their export pace. With continuous technological progress and growing market demand, large battery cells are set to play an increasingly important role in the energy storage market, providing strong support for the global energy transition.