Tin-Silicon Replaces Germanium: Solid Electrolytes Reduce Lithium Battery Costs

According to foreign media reports, Tokyo Institute of Technology researchers have developed a new technology program - germanium-free solid electrolyte can reduce the cost of solid-state lithium batteries, and is committed to the technology applied to the electric car , Communications and other industries.

Germanium-free solid electrolyte

The team published a paper in the Journal of the American Chemical Society (ACS), "Chemistry of Materials," a technology that uses tin and silicon to replace the germanium element in solid electrolytes because Two materials are more chemically stable. The new material increases the lithium ion conductivity compared to the liquid electrolyte. Commenting on his research, Ryoji Kanno and his colleagues said: "This solid electrolyte is germanium-free and may be used in all solid-state batteries in the future."

All-solid-state battery systems with solid-state electrolytes (SEs) are expected to compete for a new generation of batteries. It is estimated that such batteries can provide large power, high energy density, stable performance, safety performance also increased. Sulfide-based lithium-ion conductors have high conductivity and electrochemical windows (also known as "electrochemical windows") and good mechanical properties. To this end, many agencies are now vigorously developing solid electrolyte.

Li10GeP2S12 (LGPS) is a new member of the crystalline sulfur electrolyte product family with an electrical conductivity of 1.2 × 10 -2 S cm -1, comparable to organic liquid electrolytes. All-solid battery LiCoO2 / LGPS / In? Li using LGPS electrolyte, its charge and discharge performance is quite good. However, germanium is relatively expensive or will limit the widespread use of LGPS materials.

The type of crystal structure is also an important factor in designing a lithium ion conductor. If the structure of different types of materials are similar, and the conductivity of solid high, then the new material will be better conductive properties. The lithium ion diffusion rate of the LGPS type structure is high. In the future, both germanium-based and germanium-free germanium-based materials may be used as solid electrolytes and are in practical use.

The new material's atomic arrangement is named LSSPS. The new germanium-free material uses the result Li10.35 [Sn0.27Si1.08] P1.65S12 (Li3.45 [Sn0.09Si0.36] P0.55S4.