Liquid-solid composite electrolyte, method for manufacturing the same, and use thereof

Liquid-solid composite electrolyte with improved interface via liquid impregnation of a porous solid electrolyte

This technology is a composite electrolyte that improves physical contact at the electrode-electrolyte interface and ensures chemical stability by impregnating a porous sulfide-based solid electrolyte pellet with a liquid electrolyte of a specific composition (EC/DEC volume ratio of 2–4:6–8).

Existing issues included the inherent chemical instability of sulfide-based solid electrolytes, the formation of interfacial resistance layers with electrodes, and physical contact degradation and short-circuiting caused by micropores within the solid electrolyte.

This technology involves manufacturing a sulfide-based solid electrolyte pellet (compressed at 100–200 MPa) and impregnating its internal pores with a liquid electrolyte (containing lithium salt) consisting of ethylene carbonate (EC) and diethyl carbonate (DEC) in a volume ratio of 2–4:6–8. This enhances interfacial contact and forms a passivation layer that suppresses dendrite growth, thereby improving both the quality and productivity of secondary battery electrolytes.

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Key Features:

• Composite electrolyte comprising a pellet containing a sulfide-based solid electrolyte and a liquid electrolyte impregnated into its surface and interior
• Liquid electrolyte containing a lithium salt and an organic solvent, where the organic solvent consists of ethylene carbonate and diethyl carbonate
• Organic solvent composed of ethylene carbonate and diethyl carbonate mixed in a volume ratio of 2–4 to 6–8
• Manufacturing process involving forming a sulfide-based solid electrolyte into a pellet under pressure, followed by impregnation with a liquid electrolyte

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