Overview and Background
Achieving net zero requires scalable, low-cost energy storage technologies that avoid critical raw materials and deliver genuine lifecycle carbon reduction. Sodium-ion batteries are increasingly recognised as a sustainable alternative to lithium-ion systems, but their commercial deployment is constrained by the lack of durable, low-carbon electrode materials.
This PhD project addresses this challenge by developing biochar-based porous carbon electrodes derived from sustainable biomass feedstocks. Biochar production offers a unique dual benefit: permanent carbon sequestration and conversion of waste biomass into functional energy materials, directly aligning with engineered negative emission strategies.
The project will investigate how biomass type, pyrolysis conditions, and post-treatments control the pore hierarchy, surface chemistry, and electrochemical behaviour of biochar when used as anodes or conductive scaffolds in sodium-ion batteries. Rather than pursuing purely materials synthesis, the research will emphasise structure–property–degradation relationships under realistic electrochemical cycling, enabling predictive understanding of performance and lifetime.
A distinctive element of the project is the integration of operando and intermittent electrochemical diagnostics (e.g. impedance spectroscopy) to quantify how biochar electrodes evolve during cycling. This degradation-aware approach links directly to next-generation battery design and digital-twin-ready modelling, while remaining firmly grounded in experimentally accessible methods.
By combining biomass conversion, electrochemistry, and degradation science, this project delivers a credible route to carbon-negative electrode materials for sustainable batteries. The outcomes will be relevant to grid-scale storage, circular-economy energy systems, and future bio-integrated energy technologies, positioning the PhD researcher at the interface of materials engineering and climate-critical innovation.
Objectives:
- Produce biochar from selected biomass residues using controlled pyrolysis routes.
- Tailor pore structure and surface chemistry for sodium-ion storage.
- Quantify electrochemical performance and degradation mechanisms under cycling.
- Correlate biomass origin and processing conditions with lifetime-limiting phenomena.
- Assess carbon balance and net-zero relevance of biochar-based electrodes.
Methodology:
- Biomass selection and pyrolysis (temperature, atmosphere, residence time).
- Physical and chemical characterisation (BET, SEM/TEM, XRD, Raman, surface analysis).
- Electrode fabrication and sodium-ion half-cell testing.
- Periodic EIS and galvanostatic cycling to extract degradation descriptors.
- Comparative benchmarking against conventional hard carbon anodes.
- High-level life-cycle and carbon impact assessment.
Training:
The PhD researcher will receive structured and bespoke training covering biomass conversion processes, porous carbon and biochar synthesis, electrochemical energy storage, and degradation-aware electrochemical diagnostics. Technical training will include materials characterisation, electrode fabrication, battery testing, and data-driven interpretation of performance and lifetime behaviour. The student will also receive training in sustainability assessment, including carbon accounting and techno-environmental evaluation, to place the research within a net-zero framework.
