In the rapidly evolving landscape of energy storage and electric vehicles, sodium-ion batteries are emerging as a promising alternative to their widely adopted counterpart, lithium-ion batteries. Both technologies share fundamental electrochemical principles, differing mainly in the choice of cell materials. With the ever-growing demand for efficient and sustainable energy solutions, sodium-ion batteries are poised to capture a substantial share of the market.
Notably, sodium-ion batteries have received strong backing from national policies promoting the development of new battery technologies. A significant milestone was reached in April 2021 when MIIT, in collaboration with the National Energy Administration, released the Guidance Opinions on the Development of New Energy Storage, encompassing sodium-ion batteries for the first time.
Graph: Relevant policies on Sodium-ion Batteries
The industry chain progress: the main production technology for sodium-ion batteries has already achieved a high level of maturity.
The technology of key components for sodium-ion batteries, such as cathode materials, anode materials, electrolytes, diaphragms, and essential auxiliary materials like tabs, collectors, binders, conductive agents, and shell modules, are well-established.
As for anode materials, considerable research has been devoted to exploring various materials. Among them, layered oxides, polyanionic compounds, Prussian blue and white analogues have been the research focus. The current stage of technology is predominantly characterized by the dominance of hard carbon, complemented by the incorporation of soft carbon. Regarding electrolyte composition, sodium hexafluorophosphate electrolyte has emerged as the prevailing choice. In terms of collectors, a noteworthy development is the continuous promotion of low-cost aluminum foil as a replacement for copper foil. Furthermore, diaphragm materials in sodium-ion batteries can draw inspiration from the well-established diaphragm systems used in lithium batteries.
Graph: Sodium-ion battery industry chain
The technology for the anode of sodium-ion batteries encompasses various approaches, such as layered oxides, polyanion compounds, Prussian blue or white analogues, and tunnel-type oxide, among others. Currently, there is a growing focus on the development of layered oxides, making it the most rapidly advancing technology for sodium-ion battery anodes.
Graph: Sodium-ion Battery Systems and Characteristics
Currently, leading sodium-ion battery manufacturers like Hina Battery, CATL, Natrium, DFD, and SVOLT primarily focus on the layered oxide system for cathode materials in their production layouts. Moreover, the industrialization process of these materials has been considerably accelerated. To address the low volumetric energy density issue, major manufacturers are actively promoting the use of Prussian blue or white analogues and polyanionic compounds, which are also becoming popular choices for anode materials in sodium-ion batteries.
Sodium-ion batteries have already demonstrated their capability to meet the energy storage requirements and have found commercial applications. The key factors determining the feasibility of using sodium-ion batteries for energy storage lie in their cost and cycle life.
Research data illustrates this point. For instance, in a 30kW / (100kWh) energy storage system, where the cost can be recovered in five years and peak-valley price arbitrage amounts to 89,352 yuan, the energy storage system’s cost should not exceed 0.9 yuan/Wh. Calculating 60% of the system cost, the cost of a single sodium-ion battery should be less than 0.54 yuan/Wh. Assuming the system runs for a total of ten years, the batteries’ cycle life should reach 3650 weeks.
According to the performance parameters disclosed by Hina Battery and Natrium, the current cycle life of sodium-ion batteries can exceed 4,500 weeks, which already meets the requirements for electrochemical energy storage systems to operate for more than ten years.
Competitive Landscape: Advantages of Leading Lithium Battery Companies Continue
At present, there are primarily two types of sodium-ion battery production and manufacturing enterprises. The first group consists of traditional lithium battery manufacturers, such as CATL and Great Power, who have expanded into the sodium-ion battery field. The second group comprises new entrants, such as Hina Battery, Natrium, and Transimage, who have built their presence from scratch in the sodium-ion battery industry.
Graph: Layout of some manufacturers in the sodium-ion battery industry
During the commercialization process of sodium-ion batteries, the existing leading lithium-ion enterprises are expected to hold long-term advantages due to the structural and production process similarities between sodium-ion and lithium-ion batteries. Additionally, innovative enterprises that leverage technological advantages gained through collaboration with research institutes are likely to emerge and secure a certain market share in the growing sodium-ion battery market.
Irrespective of battery systems, the progress of materials significantly impacts battery development. The rapid growth and continuous technology upgrades in the new energy sector require a long-term perspective to ensure the healthy development of the industry, which heavily relies on ensuring safety, quality, and performance of products. Furthermore, a critical premise for achieving the commercialization and widespread adoption of energy storage lies in the reduction of energy storage system equipment prices, particularly battery prices.