A5049456950- Advanced Battery Technologies Research
- Advancements in Battery Materials
- Advanced Battery Materials and Technologies
- Supercapacitor Materials and Fabrication
- Semiconductor materials and devices
Brigham Young University
2017-2022
Battery performance is strongly correlated with electrode microstructural properties. Of the relevant properties, tortuosity factor of electrolyte transport paths through microstructure pores important as it limits battery maximum charge/discharge rate, particularly for energy-dense thick electrodes. Tortuosity however, difficult to precisely measure, and thus its estimation has been debated frequently in literature. Herein, three independent approaches have applied quantify lithium-ion The...
Ionic mass transport including electrolyte diffusivity and conductivity depends on the geometric tortuosity of electrode. This paper compares two experimental methods that determine based or conductivity. The polarization-interrupt method previously developed by our group determines in terms effective diffusivity. blocking-electrolyte proposed Gasteiger coworkers ionic is analyzed using a generalized transmission-line model to account for multiple sources impedance. Tortuosity several...
Lateral microstructure heterogeneity in anodes is known to induce nonuniform current density, state of charge, and lithium plating. This means that such electrode can limit the fast charging lithium-ion batteries. In this work, a combination experiments simulation employed understand effect mm scale lateral on cell aging. A previously developed model was extended efficiently simulate SEI formation Li plating for independent regions an electrode. The consists three parallel each described...
Tortuosity is a geometric parameter of porous electrodes that quantifies the tortuous path ions take to meet electrons in order for chemical reaction place on surface active material. Ionic resistance electrodes, which directly related tortuosity, key factor influences battery performance, and must be accurately represented models. This work intended help researchers understand able reliably determine tortuosity different electrodes. The polarization–interrupt method previously developed our...
Li-ion battery performance is greatly affected by how well ions travel through the electrodes, which in turn depends on microstructure of porous pathways electrodes. During cell formation and cycling, changes therefore lead to ionic transport. Currently what causes these their magnitude poorly understood. Changes effective conductivity diffusivity can measured terms tortuosity, a dimensionless geometric factor. This report focuses effect assembly repeated cycling tortuosity. Using method...
In addition to the characteristics of materials that make up electrode (such as active material and additives) ratios in which are combined, fabrication process itself plays an important role cell performance. This is because a contributing factor determining distribution particles microstructure electrode. The first step making uniform structure well-mixed slurry. Generally it believed too obtain reliable, high quality electrode, essential avoid agglomeration conductive additives since...
Newman-type or macrohomogeneous cell models have had a significant contribution toward designing and optimizing Li-ion batteries. In order to lower the computational cost accommodate limited experimental information, this model assumes that battery electrodes are functionally homogenous. However, assumption can be far from reality even for commercial-quality electrodes, due variability in microstructure arises during manufacturing process. Previous work our group showed electrode...
During cycling or other aging processes, the capacity of lithium-ion batteries decreases and it is also observed that cell impedance increases. In order to better understand these we are investigating electronic conductivity ionic electrodes harvested from 18650 cells have been cycled by different amounts. Effective a porous electrode film sometimes expressed in terms tortuosity, which correlated Bruggeman-type relationship [1]. A reasonably accurate method measuring tortuosity using...