Validity of the Bruggeman relation for porous electrodes

作者:Chung Ding Wen*; Ebner Martin; Ely David R; Wood Vanessa; Garcia R Edwin
来源:Modelling and Simulation in Materials Science and Engineering, 2013, 21(7): 074009.
DOI:10.1088/0965-0393/21/7/074009

摘要

The ability to engineer electrode microstructures to increase power and energy densities is critical to the development of high-energy density lithium-ion batteries. Because high tortuosities in porous electrodes are linked to lower delivered energy and power densities, in this paper, we experimentally and computationally study tortuosity and consider possible approaches to decrease it. We investigate the effect of electrode processing on the tortuosity of in-house fabricated porous electrodes, using three-dimensionally reconstructed microstructures obtained by synchrotron x-ray tomography. Computer-generated electrodes are used to understand the experimental findings and assess the impact of particle size distribution and particle packing on tortuosity and reactive area density. We highlight the limitations and tradeoffs of reducing tortuosity and develop a practical set of guidelines for active material manufacture and electrode preparation.

  • 出版日期2013-10