Alkali metal salts based on novel anions for solid polymer electrolytes

  1. QIAO, LIXIN
Dirigida por:
  1. Armand Michel Director/a

Universidad de defensa: Universidad del País Vasco - Euskal Herriko Unibertsitatea

Fecha de defensa: 13 de septiembre de 2021

Tribunal:
  1. Maria Forsyth Presidenta
  2. David Mecerreyes Molero Secretario
  3. Daniel Brandell Vocal
  4. Maria Martinez Ibañez Vocal
  5. P. Tiemblo Vocal

Tipo: Tesis

Teseo: 156716 DIALNET lock_openADDI editor

Resumen

The chemistry of the lithium salt employed plays a pivotal role in dictating the physico-chemical and electrochemical performance of any solid polymer electrolytes (SPEs), and thus also influences the performance of solid-state lithium metal batteries (SSLMBs). The lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) salt, first suggested as salt for SPEs in 1986, possesses low lattice energy and the TFSI¿ anion has a large structural flexibility, both due to the anion¿s highly delocalized negative charge and flexible center [e.g., ¿SO2¿N(¿)¿SO2¿] and has therefore been commonly used for SPE-based SSLMBs. However, low lithium-ion transference number (TLi+) and poor solid electrolyte interphase (SEI) creating properties, resulting in severe cell polarization and simultaneously notorious dendritic growth on the Li° anode. Therefore, in this thesis, several novel lithium salts were designed and synthesized to suppress anionic mobility and enhance TLi+, but without sacrificing significantly the ionic conductivity, and simultaneously with the aim of forming excellent SEI layers on the Li° anode to improve interfacial compatibility and stability towards Li° anode.