Microstructure of Carbon Fibres for Multifunctional Composites: 3D Distribution and Configuration of Atoms
Licentiate thesis, 2021

Lightweight energy storage is a must for increased driving range of electric vehicles. “Mass-less” energy storage can be achieved by directly storing energy in structural components. In such multifunctional devices called structural composite batteries, carbon fibres carry mechanical load and simultaneously act as negative battery electrode by hosting lithium ions in its microstructure. Little is known of how the microstructure of carbon fibres is optimised for multifunctionality, and deeper understanding of the configuration and the distribution of atoms in carbon fibres is needed.

Here synchrotron hard X-ray photoelectron spectroscopy and atom probe tomography are used to reveal the chemical states and three-dimensional distribution of atoms in commercial carbon fibres. This thesis presents the first ever guide for how to perform atom probe tomography on carbon fibres, and the first ever three-dimensional atomic reconstruction of a carbon fibre.

The results show that the chemical states and distribution of nitrogen heteroatoms in carbon fibres affect the electrochemical performance of the fibres. Carbon fibres performed electrochemically better with higher amount of nitrogen with pyridinic and pyrrolic configurations. Additionally, the nitrogen concentration varies throughout the carbon fibre, which may suggest that the electrochemical properties also vary throughout the carbon fibre. The knowledge provided by this thesis can lead to future carbon fibre designs with enhanced electrochemical performance for multifunctional applications.

multifunctional composites

microstructure

synchrotron hard X-ray photoelectron spectroscopy

carbon fibres

energy storage

atom probe tomography

heteroatoms

Gamma & Delta, Hörsalsvägen 7, Chalmers
Opponent: Prof. Dan Zenkert, Department of Engineering Mechanics, KTH Royal Institute of Technology, Sweden.

Author

Marcus Johansen

Chalmers, Industrial and Materials Science, Materials and manufacture

Johansen, M, Liu, F, "Best practices for analysis of carbon fibres by atom probe tomography"

Towards multifunctional batteries – insights into carbon fibres in dynamic electrochemical and mechanical processes

Swedish Energy Agency (2018-004406), 2019-01-01 -- 2023-12-31.

Driving Forces

Sustainable development

Subject Categories

Materials Engineering

Paper, Pulp and Fiber Technology

Other Materials Engineering

Composite Science and Engineering

Areas of Advance

Transport

Energy

Materials Science

Infrastructure

Chalmers Materials Analysis Laboratory

Publisher

Chalmers

Gamma & Delta, Hörsalsvägen 7, Chalmers

Online

Opponent: Prof. Dan Zenkert, Department of Engineering Mechanics, KTH Royal Institute of Technology, Sweden.

More information

Latest update

5/28/2021