Oxygen-Breathing Aqueous Sulfur Storage Battery

Technology

This lithium-air battery configuration uses transition metal catalysts to promote faster reaction kinetics and enable lower voltage requirements for Li2O2 decomposition to occur during charge. Such catalysts can include nanoparticles of molybdenum (Mo), chromium (Cr), or their respective oxides as well as a mix of any component of these. These catalyst materials promote improved reaction kinetics in an electrochemical cell composed of an anode that contains lithium and a polysulfide solution; a cathode that contains metal salts dissolved in water; and a semi-permeable separator between the anode and the cathode.  

During the charging process of a lithium-air battery, oxygen is generated in the cathode, the polysulfide in the polysulfide solution undergoes a reduction reaction in the anode, and the at least one metal ion moves from the cathode to the anode. During a discharging process of the apparatus, the oxygen is consumed in the cathode, the polysulfide oxidizes in the anode, and the at least one metal ion moves from the anode to the cathode. The transition metal promoters help improve the mechanics by which this electrochemical process occurs for a rechargeable lithium-air battery.

Problem Addressed

In a lithium-air battery, lithium (Li) and oxygen (O2) combine during discharge to form Li2O2. As the battery charges, Li2O2 must decompose to the original Li and O2 compounds. This decomposition process occurs slowly and at a high voltage. The present invention improves reaction kinetics and coulombic efficiency of a rechargeable lithium-air battery. Furthermore, this novel configuration employs use of catalyst materials as efficient as precious metals but available at a lower cost.

Advantages

• Low-cost system
• Long-duration energy storage
• Employs use of solid electrolyte configuration
• Quick charge/improved charge rates

Publications

Paiste, Denis. "Battery Challenges: Cost and Performance." Materials Processing Center, November 2, 2016.