A research team led by Professor Kim Dong-won of the Department of Chemical Engineering and SK On successfully developed a novel anode that operates at room temperature, after a joint study with the company on Lithium metal anode for sulfide-based all-solid-state batteries.
Sulfide-based Lithium metal batteries operate at temperatures higher than room temperature to ensure uniform lithium movement. However, operating batteries at high temperatures necessitates temperature maintenance modules, which, in turn, increases costs while reducing energy density. Professor Kim overcame such drawbacks by incorporating silver, a material with high lithium affinity, into the anode structure to enable operation at room temperature. This reduces the costs of maintaining high temperatures when operating the battery at high temperatures and presents an opportunity to extend battery life.
Furthermore, Professor Kim succeeded in developing technology to prevent short-circuiting of cells caused by the formation of dendrites. Sulfide-based lithium metal all-solid-state batteries have the advantage of high ionic conductivity and energy density. However, there is an issue of ununiform movement of lithium due to side reactions between the sulfide electrolyte and lithium metal. In such cases, electric current concentrates in one area, leading to dendrite formation that can grow through the electrolyte and cause cell short circuits.
To address this, Professor Kim revealed that the developed a method that can simultaneously form a Solid Electrolyte Interphase (SEI) film during the lithium-silver alloying process. The SEI film, a thin layer that forms on the surface of the electrode, acts as a protective layer. Professor Kim explained that the SEI film not only suppresses dendrite growth but also enhances process efficiency by reducing costs and time.
The paper, which contains the findings of the study, was published in ACS Applied Materials & Interfaces, a prestigious international journal in the field of materials and interfaces field recently.