Since 2023, sodium-ion batteries have made breakthroughs in various applications such as two-wheelers, light vehicles, residential energy storage, and communication energy storage. They have made significant progress in the industrialization process and are now entering the preparation phase for large-scale production.

On one hand, the three major technology routes for sodium-ion batteries have different advantages and disadvantages and are currently in a competitive phase. Additionally, the expansion of the sodium battery market will create a significant demand for upstream cathode materials, making cathode material production a key factor in promoting the industrialization of sodium batteries.

On the other hand, sodium-ion batteries have gained frequent orders in various fields this year, and production capacity planning continues to expand, putting pressure on sodium battery companies' production and delivery capabilities. Currently, several sodium battery companies are actively constructing production lines, and the first to achieve large-scale production and delivery will have a competitive advantage in the market.

As one of the most representative companies in the field of sodium batteries, Max Power has consistently focused on the anionic route. Their first anionic cathode material for large-scale production, sodium iron sulfate, offers cost advantages, excellent cycle life, and inherent safety performance, making it an ideal solution for various electric vehicle scenarios in the future.

Sodium Iron Sulfate Route: Making Strides

Historically, the progress in sodium battery cathode material technology and production capacity has been crucial for the industrialization of sodium batteries. Currently, there are three major technology routes for sodium battery cathode materials: layered oxides, anionic compounds, and Prussian blue compounds.

Among these, the Prussian blue compounds have made slower progress in industrialization due to issues such as toxic gas generation during crystallization and thermal runaway.

Layered oxides can balance energy density and cycle life and have already achieved industrialization. However, cost issues could be a key limiting factor for their commercialization in the future.

Currently, the price of lithium carbonate fluctuates in the range of 150,000 to 200,000 RMB per ton, and battery manufacturers and downstream companies have a relatively broad acceptance range for the cost of sodium battery cathode materials. However, if lithium salt prices fall to 100,000 RMB per ton, cost issues may become a significant factor hindering the expansion of sodium-ion battery applications. At that time, layered oxides may face certain pressures.

Anionic compounds offer high stability and electrochemical stability with the longest theoretical cycle life, which can reach 6000 cycles, all while maintaining low costs. They have promising prospects in various applications, including two-wheelers, low-speed vehicles, and energy storage, and their industrialization is accelerating.

This means that sodium battery companies that focus on anionic technology routes need to break through material technology and large-scale production bottlenecks, improve the cycle life and ultimate safety of sodium batteries, and achieve the lowest possible production costs to gain an early advantage in the upcoming sodium battery market battle.

As a representative company in the anionic route, Max Power uses the sodium iron sulfate system technology route, which offers multiple advantages, including low cost, high safety, and high cycle life.

In terms of cost, sodium iron sulfate, as one of the three anionic technology routes, has raw material costs ranging from 10,000 to 20,000 RMB per ton, making it the most cost-effective cathode material. Max Power also states that their large-scale production cost for prismatic cell products can be less than 0.35 RMB/Wh.

Regarding safety, sodium iron sulfate is one of the safest materials among sodium-ion materials. In October 2022, the first sodium iron sulfate (NFS) sodium-ion battery successfully passed the needle puncture test without smoking, catching fire, or exploding.
In terms of cycle performance, their "PolySodium 1" single-cell energy density is 122 Wh/kg for two-wheelers, with over 1500 cycles at room temperature. Household storage cells have an energy density of 125 Wh/kg and a cycle life exceeding 5000 cycles, while large-scale prismatic cells can achieve more than 8000 cycles.

Furthermore, from the perspective of raw materials and manufacturing processes, the sodium iron sulfate technology route has advantages when it comes to international markets, meeting the international demand for sodium batteries.

Since sodium iron sulfate does not contain precious metals and utilizes industrial solid waste such as sodium sulfate and ferrous sulfate, it aligns with low-carbon strategies. In terms of manufacturing, the dry method preparation used in sodium iron sulfate technology is simple and energy-efficient, helping overcome limitations set by European battery regulations.