Solid-state battery industry chain companies

The three main technical routes of solid-state batteries are polymers, oxides and sulfides. The difference lies in the selection of positive and negative electrode materials and electrolyte materials. However, all of them are compatible with some existing positive and negative electrode materials. At the same time, new material systems are also being developed to improve performance.

1. Cathode material:

All three types of solid-state batteries can use high-nickel ternary (such as NCM811, NCA), lithium-rich manganese-based and other high-energy density cathode materials. In the all-solid-state battery system, due to the widening of the electrochemical window, it is also possible to use higher voltage cathode materials, such as lithium nickel manganese oxide (LNMO) or other new cathode materials.

2. Negative electrode material:

In solid-state batteries, the negative electrode material attempts to change from traditional graphite to silicon-based negative electrodes with higher energy density, or even metal lithium negative electrodes. In particular, for all-solid-state batteries, lithium metal negative electrodes are considered to be the ideal choice because they solve the problems of lithium dendrite growth and safety.

3. Electrolyte materials:

Polymer solid-state batteries: use polymer electrolytes, such as polyethylene oxide (PEO), polyacrylonitrile (PAN), etc., which have good flexibility and processability, but their room temperature conductivity is low and needs to be improved to improve battery performance. Oxide solid-state batteries: use inorganic oxides as electrolytes, such as lithium lanthanum zirconium oxide (LLZO), garnet-type solid electrolytes, etc. These materials have high ionic conductivity and electrochemical stability, but may face problems such as poor interface contact with positive and negative electrode materials and large interface impedance . Sulfide solid-state batteries: use sulfide electrolytes, such as lithium sulfide-germanium-phosphorus (LiGPS), lithium sulfide-selenium (LiSeS), etc. This type of electrolyte has extremely high ionic conductivity, but may encounter problems such as poor chemical stability and violent interface reactions, which require special packaging technology and interface treatment technology to improve.

The time span for solid-state batteries to be industrialized varies according to different technical routes and development stages:

Semi-solid-state battery: Semi-solid-state battery is compatible with existing battery production lines because it introduces solid electrolyte components on the basis of liquid electrolyte, which reduces the difficulty of industrialization. Between 2023 and 2024, semi-solid-state battery technology has been installed in some new energy vehicles on a small scale, including some models of NIO and experimental models of other brands. It is expected to start large-scale mass production in 2024. The commercialization process is relatively fast, but it still needs to overcome challenges in cost, stability and standardization.

All-solid-state batteries: The industrialization process of all-solid-state batteries is relatively slow, and they face problems such as insufficient technological maturity, high cost, low ion conductivity, and short cycle life. Although scientific research institutions and companies around the world are working hard to overcome these problems, it is generally expected that the large-scale commercial application node of all-solid-state batteries may be after 2026, and some reports even point out that it may take until around 2030 to achieve large-scale production and commercial application of all-solid-state batteries.