Sulfide Barrier Coating for Solid Electrolyte

Applications

Solid inorganic electrolytes or barrier coating elements made of sulfide compounds have the potential to provide a path toward safe, reliable, and long-lasting lithium-ion batteries. Both the consumer electronics industry and the electric vehicle industry could benefit from using all-solid-state lithium-based batteries that feature this sulfide material.

Problem Addressed

Current lithium-ion batteries use liquid electrolytes, which pose significant safety challenges due to the presence of reactive and highly volatile organic solvents. Solid electrolytes, particularly those made of inorganic compounds like sulfides, offer a promising alternative for safe, reliable, stable, and long life cycle electrochemical cells. One challenge for adoption of solid-state sulfide electrolytes is high resistance present at the electrode/electrolyte interface and a narrower electrochemical stability window when compared to oxide materials.

Technology

This invention provides an inorganic material for use as a solid electrolyte in lithium-based batteries. A solid-state material comprised of a sulfide compound that does not deviate substantially from a formula of Li9S3N serves as a coating for the barrier between an anode layer and an electrolyte layer in an electrochemical cell. Additionally, this lithium-conductive material can be present in the cathode layer, the electrolyte layer, or both. The sulfide material, which has a conductivity of at least 1.0x10-7 S/cm at 25ºC, serves to protect the electrolyte from degradation due to contact with a lithium metal anode.

Advantages

  • Inorganic, solid-state electrolytes and anode barrier
  • Stability against reduction