| About this Abstract |
| Meeting |
2020 TMS Annual Meeting & Exhibition
|
| Symposium
|
Advanced Materials for Energy Conversion and Storage VI
|
| Presentation Title |
In-situ Measurement of Stresses and their Effect on Diffusion in High Energy Density Electrode Materials |
| Author(s) |
Siva Nadimpalli |
| On-Site Speaker (Planned) |
Siva Nadimpalli |
| Abstract Scope |
Solid-state diffusion of lithium through the active material is a crucial aspect of lithium-ion battery operation. There exists a large body of literature on Li diffusion coefficient measurement techniques, but none of the existent studies considered electrode stresses and the effect of stresses on the measured diffusion coefficient. In this study, a model high energy electrode material was subjected to PITT and GITT conditions while simultaneously measuring the stress evolution. It was observed that the stresses varied significantly in a single titration step during GITT experiment, which violates the assumptions of Fickian transport model. Therefore, PITT data was analyzed to obtain the chemical diffusion coefficient. As expected, the diffusion coefficient value increased considerably with Li concentration; however, the values obtained during delithiation are at least two times higher than those obtained during lithiation at any given concentration. This difference is attributed to the state of stress in the electrode. |
| Proceedings Inclusion? |
Planned: Supplemental Proceedings volume |