Low Impedance Cathode/Electrolyte Interfaces for High Energy Density Solid-State Batteries

Wachsman, Eric D.; Mo, Yifei

doi:10.2172/2007404

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DOE OSTI · 2007404

Low Impedance Cathode/Electrolyte Interfaces for High Energy Density Solid-State Batteries

Wachsman, Eric D.·Mo, Yifei

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Abstract

All-solid-state batteries (ASSBs) using a ceramic fast Li-ion conductor as a solid-state electrolyte (SSE) have been proposed as a promising strategy to significantly increase the energy density of lithium batteries. Due to their high ion conductivity and excellent stability, Li-stuffed garnets exhibit the most promising physical and chemical properties for SSEs. However, the typical microstructure, thick (>100 μm) bulk electrolyte and simple planar electrode/electrolyte interfaces, combined with poor electrode wetting of the garnet result in excessively high area specific resistances (ASRs) that severely limit achievable current density and cell energy density. In this project, the team is building on their demonstrated expertise with garnet electrolytes and ASSBs to accomplish the following: (1) engineer interfaces to overcome high NMC/LLZ interfacial impedance and interfacial degradation; (2) develop processing and fabrication techniques to achieve high loading NMC/LLZ composite cathodes with low resistance and high cyclability; and (3) integrate the NMC/LLZ cathodes into all-solid-state Li-metal/LLZ cells to achieve high-energy-density batteries.

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Wachsman, Eric D., Mo, Yifei. 2023-08-31. Low Impedance Cathode/Electrolyte Interfaces for High Energy Density Solid-State Batteries. https://doi.org/10.2172/2007404

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