عنوان

Synthesis of Lithium Sulfide Carbon Composites via Aerosol Spray Pyrolysis

Number

TL23w4n6r2

.Language of Text, Soundtrack etc

انگلیسی

Title Proper

Synthesis of Lithium Sulfide Carbon Composites via Aerosol Spray Pyrolysis

General Material Designation

[Thesis]

First Statement of Responsibility

Hart, Noam

Subsequent Statement of Responsibility

Guo, Juchen

Date of Publication, Distribution, etc.

2017

Body granting the degree

Guo, Juchen

Text preceding or following the note

2017

Text of Note

This work is an investigation of lithium sulfide carbon (Li2S@C) composites synthesis via Aerosol Spray Pyrolysis (ASP). These composites comprise the active portion of a cathode for a Li-Li2S battery, designed to outperform state of the art Li-ion cells in specific capacity (mAh/g). Producing these composites with ASP taps into the flexibility, product homogeneity and scalability of the system. This project hopes to bridge the gap between promising laboratory scale demonstrations and a commercially viable product. The key concept of this project is the rationally designed Li2S@C composite microstructure, which consists of nano-scale Li2S particles uniformly encapsulated in a carbon matrix. We propose ASP as the synthesis method due to its unique operational mechanism: reactant precursors are atomized as aerosol so that each reactant particle is an individual micro-reactor. Operation in micro-reactor scale offers negligible heat and mass transport lags, dramatically improving kinetics and microstructure control. Three different Li2S precursors are investigated; lithium nitrate, lithium carbonate and lithium acetate, respectively with sucrose as the carbon precursor. Effective Li2S-C cathodes have been produced from these three systems and each system delivers subtle microstructure and compositional differences, performing differently as a result. Lithium nitrate and sucrose derived particles appear to perform better in C/5 charging, with a specific capacity of 424 mAh/g after 40 cycles, with a capacity degradation of 0.00156. Whereas lithium carbonate and sucrose derived particles perform better in C/10 charging, with a specific capacity of 438 after 40 cycles, with a capacity degradation of 0.000612. Suggesting differences in architecture, such as porosity, particle size and particle size distribution play a role in affecting performance at different charge rates.

Scott, Eric M.

Hart, Noam

UC Riverside

Electronic name

p

[Thesis]

276903

a

Y