Measurement of Tortuosity and Porosity of Porous Battery Electrodes
Measurement of Tortuosity and Porosity of Porous Battery Electrodes
复制标题
多孔电池电极弯曲度和孔隙率的测量
DOI：
10.1149/2.073404jes
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发表时间：
2014
影响因子：
3.9
通讯作者：
J. Jorné
中科院分区：
文献类型：
--
作者：
Tyler DuBeshter;P. Sinha;A. Sakars;G. W. Fly;J. Jorné
本文报道了锂离子电池电极孔隙率和弯曲度的测量方法。本文采用[Z.Yu，RN Carter，J.Power Sour，195,1079(2010)]中的气体传输阻力测量方法来表征电极的麦克马林数(即曲度与孔隙率之比)。孔隙率是独立测量的，弯曲度是从测量的麦克马林数获得的。对车用锂离子电池的石墨电极和锂金属氧化物电极进行了测量。在孔隙率为28.5%±1.3%和21.5%±0.25%时，石墨电极和锂金属氧化物电极的扭转率分别为5.95±0.51和3.74±0.38。此外，两个电极的曲折值都明显高于Bruggeman关联式的预测值，这表明Bruggeman关联式用于锂离子电池电极建模是不适用的，应该测量感兴趣的电极的曲折度。
This paper reports methods to measure porosity and tortuosity of Li-ion battery electrodes. A gas transport resistance measurement method adapted from [Z. Yu, RN Carter, J. Power Sour., 195, 1079 (2010)] is used to characterize an electrode MacMullin number (ie the ratio of tortuosity and porosity). Porosity is measured independently, and the tortuosity is obtained from the measured MacMullin number. The measurements were carried out for graphite and Li-metal oxide electrodes taken from an automotive Li-ion battery. Tortuosities of 5.95±0.51 at 28.5%±1.3% porosity and 3.74±0.38 at a porosity of 21.5%±0.25% were measured for the graphite electrode and the Li metal oxide electrode respectively. Additionally, the tortuosity values for both electrodes were found to be significantly higher than those predicted by the Bruggeman correlation, suggesting that use of the Bruggeman correlation for Li-ion battery electrode modeling is not applicable and tortuosity should be measured for the electrodes of interest.