A carregar...
Publicação
Fabrication and characterization of silicon on rigid substrates as anodes for lithium- and sodium-ion batteries
| Nome: | Descrição: | Tamanho: | Formato: | |
|---|---|---|---|---|
| 23.86 MB | Adobe PDF |
Autores
Resumo(s)
A wide range of applications, such as powering electric vehicles, being used in consumer electronics
and providing ancillary services to the power grid, make lithium-ion batteries one of the most promising
storage technologies currently available. Due to the rapidly growing demand, major research efforts to
constantly improve the performance of battery storage systems are being made. The use of silicon as an
anode material for battery systems offers great potential due to its low cost, high abundance, and excellent specific capacity.
The main objective of this work was to fabricate silicon-based anodes with suitable properties to be used
in sodium and lithium-ion batteries. For this purpose, silicon films with suitable morphologies and chemistries deposited on substrates should be developed, resulting in working electrodes with good cyclability.
In an experimental procedure with a cold-wall reactor and silane gas as the silicon source, rigid graphite
substrates were used and deposited with silicon, by means of chemical vapour deposition. To validate
the results, the fabricated electrodes were subjected to a standard electrochemical, structural and morphological characterisation procedures.
The present chemical vapour deposition system enabled the production of samples with very different
silicon contents by varying the experimental parameters. The achieved silicon loads were in the range
of 0.1-5.1 mg cm-2
, with different morphological properties and silicon particles measuring 0.1-2 µm
diameter. The results of the electrochemical characterisation revealed that the use of NaClO4 as electrolyte compromised the process reversibility. In contrast, when an electrolytic solution of LiClO4 was
used, promising results were achieved with coulombic efficiencies of up to 80%.
Descrição
Tese de mestrado, Engenharia da Energia e Ambiente, 2022, Universidade de Lisboa, Faculdade de Ciências
Palavras-chave
deposição química de vapor baterias de iões de lítio baterias de iões de sódio silício grafite Teses de mestrado - 2023