A Tape-Casting/Freeze-Drying Approach to Prepare Low-Tortuous Graphite Electrodes

Tuesday, 15 October 2019
Grand Ballroom (The Hilton Atlanta)
D. Dang, Y. Wang, S. Gao, and Y. T. Cheng (University of Kentucky)
Lithium ion batteries (LIBs) with high energy density and fast charging capability are in high demand to satisfy the development of plug-in hybrid electric vehicle (PHEV) and full electric vehicle (EV). Limited ion transport in thick electrodes is one of the major challenges that impede the rate capability of a battery. Directional freeze-drying, with the aid of ice templating, is a feasible method to introduce low-tortuous pore structure in composite electrodes. In this study, we propose a traditional tape-casting process followed by the directional freeze-drying and calendering procedures to prepare graphite electrodes with low tortuosity. Compared with the traditional tape-casting method, the tortuosity of the graphite electrodes is effectively reduced by the subsequent freeze-drying process. Higher capacity retention and better rate capability are achieved due to enhanced ion transport capability in the low-tortuous microstructure. We confirmed that the concept of continuous tape-casting/freeze-drying is an effective and scalable approach for manufacturing high-performance thick battery electrodes.