Chris Klaassen

Tailoring Carbon Cathode Fabrication and Structure for Stable, High-Rate Lithium Air Batteries

For environmental protection, alternative energy production solutions, such as high energy density batteries, must be considered to replace the combustion of fossil fuels. Lithium Air (Li-Air) batteries have the highest theoretical energy density of any battery system, near that of gasoline combustion; however, it is a highly reactive system, so care must be taken to prevent capacity loss due to cathode passivation, cathode destruction, and parasitic side reactions. Additionally, the fabrication technique must possible on a large scale and the materials must be able to withstand the high current testing needs of industrial applications.

Li-Air batteries react lithium ions with oxygen from the air to form lithium peroxide (Li2O2), which is both reactive and electrically insulating. Therefore, the cathode must be electrically conductive, stable and chemically resilient. My work focuses on constructing and characterizing stable carbon cathodes for high-rate Li-Air battery systems via tailoring their fabrication method. Past cathode fabrication techniques have worked very well in small scale laboratory testing; however, these methods have many issues when attempting to be scaled for industrial use. Fabrication techniques like dropcasting are slow processes with poor control tolerances. Air-Controlled Electrospraying has been shown to be a much faster battery cathode fabrication technique and is easily industrially scalable. My additional research shows that electrospraying allows for better macroscale quality control and microscale surface morphology control than other cathode fabrication techniques, and these improvements have a great effect on the capacity of the battery, especially in high current density batteries.