Energy storage stands as a pivotal tool for achieving carbon reduction goals and fostering the future of a zero-carbon society, making it an indispensable facet of new energy infrastructure. With a diverse array of downstream application scenarios, the choice of core components like energy storage cell devices varies significantly based on the specific use cases.
In household energy storage, the capacity of 50-100Ah remains prevalent in the short to medium term. Key performance criteria here include long cycle life and high safety standards.
Household energy storage systems typically feature capacities ranging from 5-20 kWh. The growing trend in these products is the adoption of high-voltage platforms. High-voltage batteries achieve this by connecting multiple cells in series, resulting in a higher system voltage. This design offers advantages such as reduced current flow, decreased system interference, and improved overall efficiency.
Higher system voltage within limited space.
Elimination of DC-DC modules, reducing overall system costs.
Mature product solutions.
Considering these factors, 50-100Ah batteries remain the mainstream choice for household energy storage in the short term. These batteries need to excel in long cycle life, wide temperature tolerance, charge-discharge rate, and high volumetric energy density.
The electricity storage sector is transitioning towards large-capacity cells and modularization. This field spans power generation, grid management, and industrial applications, categorized into capacity and power types.
Capacity-type applications demand high cycle life and a wide temperature operating range, while power-type energy storage systems require rapid charge-discharge capabilities, prioritizing cycle life and charge-discharge rates over energy density.
Battery routes in electricity storage encompass square, cylindrical, and pouch cells paired with iron phosphate, ternary, or lithium titanate chemistries. Considering factors like safety, cycle life, and regulatory policies, domestic markets mainly favor square iron phosphate cells.
In terms of battery cell technology, there is a clear trend toward large-capacity, long-cycle life models. Leading companies are releasing energy storage cells with large capacities exceeding 280Ah and cycle life surpassing 12,000 cycles, with energy densities generally exceeding 150Wh/kg. These large cells offer various advantages, including higher volumetric energy density, reduced component usage, cost-effectiveness, and simplified assembly processes.
Portable energy storage overlaps significantly with consumer electronics (3C) in terms of design philosophy and use cases, making it heavily influenced by the lithium battery supply chain. The primary cell types for portable energy storage are cylindrical 18650 cells, with 21700 cylindrical cells and larger cylindrical cells gradually gaining traction in scenarios with more stringent energy density requirements.
Despite the dominance of cylindrical cells, some domestic lithium battery brands are exploring soft pouch and square cell production to cater to the growing demand for portable energy storage. However, due to challenges in ensuring consistent performance with soft pouch cells, their market penetration remains limited.
As the energy storage landscape evolves, it's evident that the requirements for energy storage cell products vary significantly across different application scenarios. Whether it's household energy storage, electricity storage, or portable energy solutions, the performance demands are shaped by specific needs, from long cycle life to rapid charge-discharge capabilities.
The future holds exciting prospects for energy storage cells as they continue to adapt to a multitude of applications, ultimately contributing to a more sustainable and energy-efficient world.
