Analysis of The Main Technical Routes of Solid-state Batteries: Who Will Dominate The Energy Storage System?

Solid-state batteries are becoming the focus of the new energy field due to their revolutionary design of replacing liquid electrolytes with solid electrolytes. They not only completely eliminate safety hazards such as thermal runaway and electrolyte leakage, but also increase energy density to a theoretical value of over 500Wh/kg and a cycle life of over 2,000 times, injecting new momentum into the upgrade of energy storage systems and the development of new energy vehicles.The following article will provide an in-depth comparison of the three major technical routes for solid-state batteries.

Sulfide electrolytes are the best in the industry with their ionic conductivity (10⁻³ S/cm at room temperature), and are suitable for all-solid-state systems, with a theoretical energy density approaching 500Wh/kg. CATL has developed a 500Wh/kg-level 20Ah sample, and Gotion High-Tech has even achieved road testing of all-solid-state batteries. However, its air sensitivity and high cost remain bottlenecks. Industry innovator Ruigu New Materials has launched the N series of water-soluble sulfide electrolytes, which reduce production costs through a composite system and promote the industrialization process.

​​Application of energy storage systems: The high energy density of sulfide batteries can significantly improve the power output capacity of grid-level energy storage projects, especially for the stable power supply requirements in extreme environments.

Polymer electrolytes are known for their strong processability and low cost, and have been used in drones, wearable devices and other fields. Although the CNC-PAN composite material developed by Qingdao University of Science and Technology has a low room temperature conductivity (needs to work above 60°C), its tensile strength reaches 9.5MPa. ProLogium's fourth-generation lithium ceramic battery (LCB) provides a safer choice for consumer electronics with a volume energy density of 749Wh/L.

​​Technical limitations​​: Low room temperature conductivity and energy density ceiling (≤300Wh/kg) limit its large-scale application in energy storage systems.

The high safety and long life of all-solid-state batteries will promote the implementation of new energy models such as photovoltaic and energy storage integration and virtual power plants. From CATL's 500Wh/kg sample to Ruigu New Materials' thousand-ton production line, China is building a new order for the energy storage industry through technological iteration.