A project team composed of multiple parties, including the Institute of Physics of the Chinese Academy of Sciences, has made a significant breakthrough by successfully addressing the technical challenges of sodium-ion batteries in large-scale energy storage. They have developed a long-life, wide-temperature-range, and high-safety sodium-ion energy storage battery, along with the first large-capacity sodium-ion battery energy storage system, reaching an internationally leading level of overall technology.
Compared to lithium batteries, sodium batteries offer excellent performance in high and low temperatures, as well as superior safety characteristics. Additionally, sodium resources are abundant, and related raw materials are more accessible. The cost of sodium-ion batteries can be reduced by approximately 30% compared to phosphate-iron lithium batteries with similar performance.
Currently, sodium batteries are gradually being applied in energy storage, electric two-wheeled vehicles, and new energy vehicle markets. Sodium-ion batteries share a high degree of similarity with lithium batteries in terms of their composition, working principles, and production processes.
One of the main advantages of sodium-ion batteries lies in their cost-effectiveness, primarily due to the use of positive electrode materials and current collectors. Compared to positive electrode materials in phosphate iron lithium batteries, the copper-based positive electrode materials in sodium-ion batteries reduce costs by nearly 60%.
Additionally, because sodium and aluminum do not undergo alloying reactions, current collectors can be entirely replaced with aluminum foil instead of copper foil, thereby reducing costs by nearly 70%. In the long term, achieving large-scale industrialization and realizing theoretical low costs for sodium-ion batteries will still require considerable time, with mass commercial applications expected around 2025.
Sodium batteries largely inherit the mature industrial chain of lithium batteries. The core components of sodium-ion batteries include positive and negative electrodes, electrolytes, and separators, with the current supply of positive and negative electrodes as well as electrolytes not yet stable at a large scale.
Due to limited lithium mineral resources (only accounting for 0.0065%) and uneven distribution leading to sharp price increases, upstream resource suppliers are facing challenges. In contrast, sodium mineral resources are abundant (accounting for as much as 2.75%) and widely distributed without geographical restrictions.
The main changes in the sodium battery industry chain are evident in the middle and positive electrode materials sectors. Currently, sodium-ion battery positive electrode material systems mainly consist of layered transition metal oxides, polyanionic compounds, and Prussian blue compounds.
Layered oxides are favored due to their good industrialization foundation, polyanionic compounds are known for excellent cycling performance but are limited by higher costs, lower energy density, and rate performance. Prussian blue/white compounds offer advantages in terms of cost and rate performance.
The negative electrode, electrolyte, and separator segments of the sodium battery industry chain generally maintain the existing competitive landscape, no longer requiring copper foil for current collectors.
As the industrial system is still in its early commercialization stage, the competitive landscape is subject to further observation, but leading companies have demonstrated early advantages. With mass production in sight, costs are expected to decrease further, potentially driving continuous expansion in the sodium battery market.