Microstructure Characterization and Modeling for Improved Electrode Design

Smith, Kandler A

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DOE OSTI · 1468331

Microstructure Characterization and Modeling for Improved Electrode Design

Smith, Kandler A

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Abstract

As part of DOE's Computer-Aided Engineering of Batteries Program, the National Renewable Energy Laboratory is developing detailed models capturing the influence of lithium-ion battery electrode design, recipe and processing on the electrode's microstructure and relating that microstructure to device-level performance. Given the difficulty in obtaining 3D microstructural images of the electrode's inert components, team member Purdue University developed an algorithm to computationally generate the so-called carbon-binder domain (CBD) for any given recipe. Mesoscale models explore the device-level impact of the CBD phase on multiple idealized and actual electrode geometries. With the inclusion of this CBD phase, microstructure models are used to predict the tortuosity of 14 different graphite and NMC electrode designs. Tortuosity predictions are shown in good agreement with experimental direct measurement and electrochemical rate studies.

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25 ENERGY STORAGE 30 DIRECT ENERGY CONVERSION carbon-binder domain computer-aided engineering electrochemical model electrode microstructure lithium-ion battery mesoscale model microstructure model morphology tortuosity

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Smith, Kandler A. 2018-08-27. Microstructure Characterization and Modeling for Improved Electrode Design. https://www.osti.gov/biblio/1468331

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