dc.contributor.author | Eldesoky, Ahmed | |
dc.date.accessioned | 2023-06-06T14:24:24Z | |
dc.date.available | 2023-06-06T14:24:24Z | |
dc.date.issued | 2023-06-02 | |
dc.identifier.uri | http://hdl.handle.net/10222/82625 | |
dc.description.abstract | The skyrocketing production of electric vehicles means fewer batteries for energy storage and a strain on Li, Ni, and Co metal supplies. Therefore, improving the lifetime of Li-ion cell chemistries is crucial to enable vehicle-to-grid applications that can support the grid, and maximizing the energy output of Li-ion cells. This thesis considers ways to understand Li-ion cell failure and improve the lifetime.
First, the impact of cycling conditions on the lifetime of Li(Ni0.8Mn0.1Co0.1)O2 (NMC811) cells was studied, and various post-mortem characterizations tools were used to probe cell degradation. Second, we examined the role that the graphite negative electrode material plays in the lifetime of NMC811 cells, and proposed a cell design that combines competitive graphite materials with ideal cycling conditions for NMC811 to yield long-lived cells.
Next, we studied the impact of electrolyte, Li excess, particle size, and NMC blending of the performance and degradation of Li1+xMn2-xO4 (LMO) cells at different temperatures. This led to the identification of an optimal LMO composition (i.e., x in Li1+xMn2-xO4), and development of mixed salt electrolyte systems that can hinder Mn dissolution and improve cell lifetime. Using this knowledge, we designed cells with large “single-crystalline” LMO particles and mixed salt electrolytes with competitive lifetime. Finally, we pivoted from the LMO system and used the mixed salt electrolytes to improve the high-temperature cycling performance of LiFePO4 cells. | en_US |
dc.language.iso | en | en_US |
dc.subject | Li-ion Cells | en_US |
dc.subject | Energy Storage | en_US |
dc.subject | Li-ion Electrolytes | en_US |
dc.title | Strategies to Understand Li-ion Cell Failure and Improve Lifetime | en_US |
dc.type | Thesis | en_US |
dc.date.defence | 2023-05-25 | |
dc.contributor.department | Department of Chemistry | en_US |
dc.contributor.degree | Doctor of Philosophy | en_US |
dc.contributor.external-examiner | Dirk Uwe Sauer | en_US |
dc.contributor.graduate-coordinator | Peng Zhang | en_US |
dc.contributor.thesis-reader | Michael Metzger | en_US |
dc.contributor.thesis-reader | Michael Freund | en_US |
dc.contributor.thesis-reader | Saurabh Chitnis | en_US |
dc.contributor.thesis-supervisor | Jeff Dahn | en_US |
dc.contributor.ethics-approval | Not Applicable | en_US |
dc.contributor.manuscripts | Not Applicable | en_US |
dc.contributor.copyright-release | Not Applicable | en_US |