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PhD Thesis Defense: Yiwen Zhang

Dec

15

Thursday
1:00pm - 3:00pm ET

Online

For info on how to attend this videoconference, email yiwen.zhang.th@dartmouth.edu.

"Electrolyte synthesis and engineering for alkali metal batteries"

Abstract

Batteries have been in increasing demand over the last decade for portable electronic devices, electric vehicles, and grid-scale energy storage systems. While the electrode materials define the characteristic features of a battery system, the composition of the electrolyte is of critical importance and needs to be engineered for different battery systems to ensure superior electrochemical performance. In this thesis, the basic functionality and fundamental mechanism of the electrolytes in battery systems are first introduced. Then, three major electrolyte engineering strategies are demonstrated, including electrolyte composition formulation, electrolyte-electrode component modification, and function-oriented electrolyte design. Firstly, the low-temperature capacity restraint of lithium metal batteries is addressed by introducing an electrolyte additive that constructs a robust solid-electrolyte interphase layer on the surface of lithium metal electrode. Secondly, solid-state electrolyte paired with nano-architectured sodium sulfide/carbon composite cathode in sodium sulfur batteries are demonstrated, which effectively prevent the shuttling of polysulfides and alleviate the capacity decay over cycling. Lastly, the contact issue at the electrode/electrolyte interface in all-solid-state sodium sulfur batteries is tackled by the design and synthesis of a novel solid-state sodium thiophosphate electrolyte.

Committee

  • Prof Weiyang Li (Chairman)
  • Prof Jifeng Liu
  • Prof William Scheideler
  • Prof Yuan Yang (external)

Contact

For more information, contact Theresa Fuller at theresa.d.fuller@dartmouth.edu.