Important Dates
Guest Talk - Prof. Dr. Joachim Spatz (Max-Planck-Institute for Medical Research)
19. November 2024, 11 a.m.
S101, FAN-A building
Prof. Dr. Joachim Spatz will be giving a presentation about "Metal Fiber Fleece Enables Fast Li-ion Diffusion in Thick Electrodes".
Lithium battery cells suffer from limited lithium-ion mobility and high internal electrical resistance. Therefore, standard cells require electrodes with a thickness of less than 100 µm to keep charge carrier paths in the electrodes short to enable efficient charging. For the first time, we describe electrochemically-functional, ultra-thick anodes of up to 1.7 mm and 40 mAh/cm2 areal capacity. Common thin metal foil current collectors are replaced with an elastic, truly 3-dimensional fleece made of ultrafine copper fibers. By galvanostatic intermittent titration technique we demonstrate increased diffusivity in ultra-thick anodes, possible due to perfect infiltration of the metal fleece into the active material which opens channels for ultrafast lithium-ion diffusion. A microfluidic chip in combination with Raman spectroscopy and molecular initio-dynamics quantitatively and mechanistically demonstrate the increased lithium-ion diffusivity on the fleece’s charged copper surfaces. This demonstrates a new, previously unknown mechanism for improving the diffusivity of lithiumions which enables ultra-thick electrodes by simultaneously increasing energy density.