An Efficient Halogen-Free Electrolyte for Use in Rechargeable Magnesium Batteries

Area of Science:

• Electrochemistry
• Materials Science
• Energy Storage

Background:

• Rechargeable magnesium batteries are promising energy storage devices.
• Current electrolytes often rely on chloride-based systems, which are corrosive and limit performance.
• Developing stable, non-corrosive electrolytes is crucial for practical applications.

Purpose of the Study:

• To introduce a novel, halogen-free magnesium salt for rechargeable magnesium batteries.
• To demonstrate the compatibility and superior oxidative stability of the new electrolyte system.
• To enable high-voltage cathode testing using standardized coin cells.

Main Methods:

• Synthesis of a simple-type Mg salt based on monocarborane anions (CB11H12-).
• Formulation of the Mg(CB11H12)2/tetraglyme (MMC/G4) electrolyte system.
• Electrochemical testing, including anodic stability and compatibility with Mg metal.

Main Results:

• The monocarborane-based Mg salt is the first halogen-free, simple-type Mg salt compatible with Mg metal.
• The Mg(CB11H12)2/tetraglyme electrolyte exhibits oxidative stability exceeding that of conventional ether solvents.
• The non-corrosive nature of the electrolyte allows for standardized high-voltage cathode testing in coin cells.

Conclusions:

• The development of the Mg(CB11H12)2/tetraglyme electrolyte represents a significant advancement in magnesium battery research.
• This halogen-free system overcomes the limitations of chloride-based electrolytes, particularly corrosion.
• The findings have profound implications for the realization of practical, high-performance rechargeable magnesium batteries.