Closed-loop cathode recycling in solid-state batteries enabled by supramolecular electrolytes

Area of Science:

• Materials Science
• Electrochemistry
• Sustainable Chemistry

Background:

• Recycling solid-state batteries (SSBs) is challenging due to the difficulty in separating components like cathodes and solid electrolytes.
• Current methods for deconstructing and remanufacturing SSB materials are intensive and costly.

Purpose of the Study:

• To design novel electrolytes that facilitate both the fabrication of high-performance SSBs and their end-of-life recycling.
• To develop a method for efficient recovery and reuse of cathode materials from SSBs.

Main Methods:

• Development of supramolecular organo-ionic (ORION) electrolytes with tunable viscoelastic properties.
• Fabrication and testing of SSBs using ORION electrolytes, lithium metal anodes, and LFP/NMC cathodes.
• Implementation of a low-temperature solvent process for cathode isolation and cell refurbishment.

Main Results:

• ORION electrolytes exhibit viscoelastic solid behavior at operating temperatures (-40°C to 45°C) and viscoelastic liquid behavior above 100°C.
• SSBs with ORION electrolytes demonstrated stable cycling for hundreds of cycles at 45°C with <20% capacity fade.
• Refurbished cells using recycled cathodes recovered 90% of initial capacity and retained 84% after 100 cycles in their second life.

Conclusions:

• ORION electrolytes offer a viable solution for creating recyclable solid-state batteries.
• The developed recycling process significantly enhances the sustainability and economic feasibility of SSB technology.
• This approach paves the way for a circular economy in advanced battery manufacturing.