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The Impact Of Calendering On The Electronic Conductivity Heterogenity Of Lithium-Ion Electrode Films, Emilee Elizabeth Hunter
The Impact Of Calendering On The Electronic Conductivity Heterogenity Of Lithium-Ion Electrode Films, Emilee Elizabeth Hunter
Theses and Dissertations
Advancements in Li-ion batteries are needed especially for the development of electric vehicles and stationary energy storage. Prior research has shown mesoscale variations in electrode electronic conductive properties, which can cause capacity loss and uneven electrochemical behavior of Li-ion batteries. A micro-four-line probe (μ4LP) was used to measure electronic conductivity and contact resistance over mm-length scales in that prior work. This work describes improvements to overcome the challenge of unreliable surface contact between theμ4LP and the sample. Ultimately a second generation flexible probe called the micro-radial-surface probe (μ4LP) was designed and produced. The test fixture was also optimized to obtain …
Understanding The Relationships Between Ion Transport, Electrode Heterogeneity, And Li-Ion Cell Degradation Through Modeling And Experiment, Fezzeh Pouraghajansarhamami
Understanding The Relationships Between Ion Transport, Electrode Heterogeneity, And Li-Ion Cell Degradation Through Modeling And Experiment, Fezzeh Pouraghajansarhamami
Theses and Dissertations
Electrode microstructure directly affects ion and electron transport and, in turn, has a strong correlation to battery performance. Understanding the separate yet complementary effects of ionic and electronic transport in cell behavior is a challenge. This work provides through a combination of experiments and modeling a better understanding of the relationship between three aspects of the cell: ion transport within the electrode, electrode uniformity, and cell degradation. The first part of this work compares two experimental methods that determine ion transport in terms of tortuosity, a dimensionless geometric factor. The polarization-interrupt and blocking-electrolyte methods measure effective diffusivity and conductivity, respectively. …