Spider Silk-Inspired Binder Design for Flexible Lithium-Ion Battery with High Durability

Area of Science:

• Materials Science
• Electrochemistry
• Polymer Science

Background:

• Flexible lithium-ion batteries (LIBs) require simultaneous high energy density and mechanical durability.
• Achieving stable electrode-current collector contact is challenging, especially for high-loading electrodes and deformed batteries.

Purpose of the Study:

• To develop a novel binder for flexible LIBs inspired by spider silk.
• To improve electrode integrity, adhesion, and overall battery performance under mechanical stress.

Main Methods:

• Synthesized a binder by cross-linking supramolecular poly(urethane-urea) with polyacrylic acid.
• Investigated the binder's properties, including elastic restorability and adhesion.
• Tested the performance of flexible LIBs using the developed binder under dynamic deformation.

Main Results:

• The binder exhibits super high elastic restorability and extraordinary adhesion due to engineered hydrogen-bonding segments.
• Electrodes maintained intact morphology without disintegration even under significant deformation.
• Flexible LIBs demonstrated stable cycling and voltage output during dynamic deformation tests.
• Achieved a high energy density of 420 Wh L⁻¹ in the flexible LIBs.

Conclusions:

• The spider silk-inspired binder offers a promising solution for flexible LIBs with high-loading mass.
• The binder design enhances mechanical durability and maintains performance under deformation.
• This work provides a valuable material solution for advanced flexible energy storage devices.