Electrodes for high energy batteries
Electrochemical energy storage beyond the lithium-ion battery needs new concepts and materials that produce cheaper and more powerful batteries. Research focuses are conversion-based cell chemistry, such as that found in metal-air batteries. In particular, the Li-O2 system offers theoretically an excellent energy density. In order to achieve the promised high capacities, electrodes with an adapted pore structure and a large electrochemically active surface area are required.
With the aim of an optimized reaction interface, dispersion electrodes were developed as part of an experimental investigation of Li-O2 batteries. By directly mixing a conductive cathode active material with a liquid electrolyte, a dispersion is produced that can be used as a functional electrode in batteries. The mixture is absorbed by a substrate, which at the same time enables the transport of electricity and substance in relatively thick electrodes. In contrast to conventional solid-state electrodes, which are wetted with electrolyte, the electrochemically active interface of a dispersion electrode can be maximized via the mixing ratio of solid and liquid. Using the example of Li-O2 batteries, the proof of concept was provided that gas diffusion electrodes can also function without a rigid or elaborately produced pore structure.
Simple process control (without additional solvents or binders)
Material selection and mixing ratio can be adjusted
Transferable to other electrochemical systems (e.g. electrochemical reactors, electrolyzers)
European patent application pending, US patent application pending and German patent application pending
Proof of concept
RWTH Technology #2145
Fields of application electrochemistry; Batteries; Fuel cells
Keywords #dispersion; #lithium-oxygen batteries #Li-Ion