Investigation into Lithium-Ion Conductivity and Redox Stability of Selenium-Doped Lithium Lanthanum Titanate

Selenium-doped lithium lanthanum titanate of composition Li₀.₃₃La₀.₅₆Ti₁₋ₓSeₓO3 (x = 0, 0.025, 0.050, 0.075) was attempted using a two-step conventional synthesis process to investigate the potential of the material as a solid-state electrolyte in lithium-ion batteries. Impedance spectroscopy data yielded a maximum room temperature bulk conductivity of (1.73 ± 0.10) x 10⁻³ S cm⁻¹ (EBulk = 0.35 ± 0.03 eV) and grain boundary conductivity of (1.20 ± 0.10) x 10⁻⁴ S cm⁻¹ (EGB = 0.37 ± 0.01 eV) for nominal composition x = 0.050. Preliminary stability measurements through three-electrode cyclic voltammetry suggests potential for LLTO stabilization against Li metal anode through further selenium substitution. However, further work is required to confirm the exact elemental composition of selenium-doped samples.

Name thesis:degree_name

Bachelor

Department dc:contributor.department

Massachusetts Institute of Technology. Department of Mechanical Engineering

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2023

Author dc:creator

• Hu, Lambert

Advisor dc:contributor.advisor

• Shao-Horn, Yang

Statement dc:rights

• In Copyright - Educational Use Permitted
• Copyright retained by author(s)

Licence dc:rights.uri

• https://rightsstatements.org/page/InC-EDU/1.0/

Handle dc:identifier.uri

https://hdl.handle.net/1721.1/151906

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/151906