Current Collector Engineering for New Efficient Bioresorbable Sodium-Ion Batteries.

Area of Science:

• Materials Science
• Electrochemistry
• Biomedical Engineering

Background:

• Bioresorbable energy sources are crucial for implantable devices to avoid secondary surgeries.
• Developing stable and high-performance bioresorbable batteries presents significant challenges in resorbtronics.

Purpose of the Study:

• To present an alternative fabrication strategy for bioresorbable quasi-solid sodium-ion batteries.
• To investigate the impact of different current collectors (Mo and Mg) on battery performance and biocompatibility.

Main Methods:

• Fabrication of quasi-solid sodium-ion batteries using Mo or Mg thin films as current collectors.
• Characterization using scanning electron microscopy, X-ray photoelectron spectroscopy, and electrochemical techniques.
• In vitro cytotoxicity assays (ISO 10993) and in vivo implantation studies in animal models.

Main Results:

• Molybdenum (Mo)-based batteries achieved a discharge capacity of 6.8 mAh cm⁻² at C/2, outperforming magnesium (Mg)-based batteries.
• Mo-based batteries showed stable cycling with 86% capacity retention after 100 cycles at 2C.
• In vitro and in vivo studies confirmed the non-cytotoxicity and safe degradation of Mo-based batteries.

Conclusions:

• The choice of current collector critically impacts bioresorbable battery performance, with Mo offering superior electrochemical properties.
• Mo-based bioresorbable sodium-ion batteries are biocompatible and exhibit tunable operational lifetimes.
• This fabrication strategy provides a viable pathway for developing advanced resorbtronic energy sources.