Ab initio modelling of alkali-ion battery electrolyte properties
Doktorsavhandling, 2014

Lithium-ion batteries are omnipresent in modern electronics. They can be found in laptops, mobile phones and electric vehicles. However, there is room for both improvement, as the thermal instability of the dominant lithium salt used in batteries today, LiPF6, causes safety concerns, and more fundamental changes, as there is a limited amount of lithium available – resulting in sodium-ion batteries being a nascent field of study. This thesis looks in detail at some underlying fundamental features affecting properties of electrolytes of both lithium-ion and sodium-ion batteries. These properties include the oxidative stability of the anions of the lithium and sodium salts (important for voltage and safety); the cation-anion interaction strength (important for conductivity); the solvation of the lithium and sodium cations in the common carbonate solvents (important for conductivity and the (de-)solvation at the anodes/cathodes); and the thermal stability of the anions and the possible decomposition reactions (important for safety). The properties are mainly studied for a number of both novel and well established anions. Some of the novel anions involve completely new concepts for anion design for alkali-ion battery electrolytes. The systems are studied with a number of ab initio methods, most based on density functional theory (DFT). These include high level calculations of benchmark quality. The applicability of DFT and the selection of DFT functionals is also studied. Novel calculation strategies were employed to understand thermal decomposition.

Batteries

sodium salts

lithium salts

ab initio

DFT

electrolytes

anions

Kollektorn, MC2, Kemivägen 9, Chalmers University of Technology
Opponent: Frank Jensen, Associate Professor, Department of Chemistry, Aarhus University, Denmark

Författare

Erlendur Jonsson

Chalmers, Teknisk fysik, Kondenserade materiens fysik

Modern battery electrolytes: Ion-ion interactions in Li+/Na+ conductors from DFT calculations

Physical Chemistry Chemical Physics,; Vol. 14(2012)p. 10774-10779

Artikel i vetenskaplig tidskrift

Novel pseudo-delocalized anions for lithium battery electrolytes

Physical Chemistry Chemical Physics,; Vol. 14(2012)p. 6021-6025

Artikel i vetenskaplig tidskrift

Styrkeområden

Energi

Materialvetenskap

Infrastruktur

C3SE (Chalmers Centre for Computational Science and Engineering)

Ämneskategorier

Annan fysik

ISBN

978-91-7385-971-4

Doktorsavhandlingar vid Chalmers tekniska högskola. Ny serie: 0346-718X

Kollektorn, MC2, Kemivägen 9, Chalmers University of Technology

Opponent: Frank Jensen, Associate Professor, Department of Chemistry, Aarhus University, Denmark