Energy Materials & Interfaces (EMI)
We integrate advanced experimental characterization, electrochemical and optical analysis, and physics-based and data-driven modeling to understand fundamental mechanisms and translate them into improved materials, devices, and energy technologies.
Electrochemical Energy Conversion and Storage
Led by Professor Yaolin Xu
Our research focuses on understanding and engineering materials, interfaces, and processes for electrochemical energy conversion and storage. We combine advanced operando and ex situ characterization, including cryo-EM, in situ TEM, electrochemical AFM (EC-AFM), and synchrotron- and neutron-based spectroscopy, with electrochemical analysis, materials and interface engineering, and physics-based and data-driven modeling to reveal fundamental mechanisms and link them to electrochemical performance and durability.
Our research spans rechargeable batteries and electrochemical ammonia synthesis, including battery materials and interfaces, fast and pulsed charging, degradation and failure mechanisms, state estimation and lifetime prediction, and lithium-mediated nitrogen reduction for green ammonia production.
Solar Energy Research
Led by University Lecturer Janne Halme
Our solar energy research focuses on developing sustainable photovoltaic and photoelectrochemical technologies by integrating materials science, device physics, optics, and electrochemistry.
Our research spans coloured and flexible photovoltaics, building-integrated solar technologies, photoelectrochemical energy conversion, and nature-inclusive and regenerative approaches to renewable energy systems.
Group News and Events
- September 1, 2026 — EMI's Unite! Seed Fund proposal ElectRAmmonia, on electrode and reactor co-design for high-rate electrochemical green ammonia production, was selected for funding.
- August 18, 2026 — Midterm presentation: “Green Ammonia with Lithium Mediated Nitrogen Reduction – Engineering and Understanding Solid Electrolyte Interfaces” by Haoxuan You.
- August 1, 2026 — Welcome Allyson Robert and Subham Khange, who joined the EMI group as Postdoctoral Researchers.
- July 15, 2026 — Welcome Laela Ezra, who joined the EMI group as a Postdoctoral Researcher.
- July 10, 2026 — The EMI team enjoyed a summer event in Nuuksio National Park.
- July 1, 2026 — Welcome Jinghua Sun, who joined the EMI group as a Postdoctoral Researcher.
- February 1, 2026 — Welcome Miseung Kim, who joined the EMI group as a Doctoral Researcher.
- November 1, 2025 — Welcome Shansong Bi, who joined the EMI group as a Doctoral Researcher.
- October 1, 2025 — Welcome Lume Xi Lin, who joined the EMI group as a Doctoral Researcher.
- September 1, 2025 — Welcome Ziyi Wan, who joined the EMI group as a Doctoral Researcher.
- May 1, 2025 — Welcome Antti-Jussi Kallio, who joined the EMI group as a Postdoctoral Researcher.
- January 1, 2025 — Welcome Haoxuan You, who joined the EMI group as a Doctoral Researcher.
Selected Research Projects
Our research projects address fundamental and applied challenges across electrochemical energy storage, energy conversion, and solar technologies.
Investigating how pulse charging influences battery materials, interfaces, degradation, and lifetime by integrating electrochemical testing, advanced characterization, and modeling.
Principal Investigator: Prof. Dr. Yaolin Xu
2025–2029
Developing advanced charging strategies and battery models to enable fast charging while extending battery lifetime, preserving performance, and improving safety.
Principal Investigator: Prof. Dr. Yaolin Xu
2026–2028
Advancing electrochemical nitrogen reduction toward sustainable ammonia production through mechanistic understanding and engineering of lithium-mediated electrochemical processes.
Principal Investigator: Prof. Dr. Yaolin Xu
2026–2029
Developing customizable, efficient, and reliable coloured photovoltaic solutions using scalable roll-to-roll technologies for integration into buildings and infrastructure.
Principal Investigator: Dr. Janne Halme
2026–2029
Research Facilities & Infrastructure
EMI combines dedicated in-house laboratories with access to advanced shared research infrastructures at Aalto University and partner institutions. Our facilities support electrochemical cell preparation, testing, and cycling, advanced characterization, and the development and validation of new energy technologies.
In-house facilities
- Controlled-atmosphere glovebox facilities
- Electrochemical characterization and battery cycling systems
- Flow and batch electrochemical reactor systems for optimization and operando studies
- In situ and ex situ spectroscopy, imaging, and structural characterization
- Solar cell printing lab
- Photovoltaic characterization lab
Advanced shared infrastructure
- Center for X-ray Spectroscopy, University of Helsinki
Advanced laboratory-based X-ray absorption and emission spectroscopy for structural, chemical, and operando characterization. - Nanomicroscopy Center (NMC)
Advanced microscopy and X-ray characterization through Aalto University's OtaNano infrastructure.
The Aalto University Nanomicroscopy Center (NMC) provides high resolution microscopy to researchers, who come to work and collaborate using this high-quality equipment. The center is accessible to everyone.
Electrochemical Energy Research Team
Yaolin Xu
Haoxuan You
Antti-Jussi Kallio
Ziyi Wan
Lume Xi Lin
Shansong Bi
Miseung Kim
Jinghua Sun
Laela Ezra
Solar Energy Research Team
Janne Halme
Liza Helen Kuttappassery
Ongoing Thesis Students
Yanping Gao
Joni Ranta
Theses, Former Members & Teaching
Master's Theses
- Alessia Cicchino - Data-driven early screening of pulse charging protocols for lifetime-aware battery charging design. 2026.
- Aurora Cuffari - Data-driven rolling prediction of thermal runaway risk in thermal abuse tests. 2026.
Former Master's Students
- Alessia Cicchino — Former Visiting Master's Student
Currently continuing her Master's studies at Politecnico di Torino, Italy. - Aurora Cuffari — Former Visiting Master's Student
Currently continuing her Master's studies at Politecnico di Torino, Italy.
Battery Technologies
PHYS-E0433 — Introduction to Battery Technologies
Prof. Dr. Yaolin Xu
An introduction to rechargeable battery technologies spanning fundamental electrochemistry, battery materials and characterization, degradation and modeling, and emerging battery chemistries. The course combines lectures with hands-on battery fabrication, testing, and performance analysis.
Solar Energy and Multidisciplinary Energy Studies
PHYS-E6570 — Solar Energy Engineering
Dr. Janne Halme
A comprehensive introduction to solar energy engineering, with emphasis on photovoltaic technologies, solar-cell operation and performance, and the physical and engineering principles underlying solar-energy conversion.
PHYS-C1380 — Multi-disciplinary Energy Perspectives
Dr. Janne Halme
Explores energy challenges from technological, economic, societal, behavioral, and environmental perspectives. The course combines contributions from multiple disciplines with group work on topical energy questions.
Latest Publications
Electrothermal performance in electrically heating textiles
Influence of deposition temperature and thickness of ALD-TiO2 on planar perovskite solar cell performance
An investigation into the application of incremental capacity analysis in harsh measurement conditions : focusing on the VC model-based ICA technique and the influence of training set selection on the SOH model
Protocol-aware standardization of relaxation-induced kinetic masking in incremental capacity fingerprints of lithium-ion batteries
Advancing cryogenic electron microscopy towards the mechanistic understanding of metal electrodes and interphases
Toward near-100% initial Coulombic efficiency of Si anodes through irreducible solid electrolyte-induced dynamic interphases
Degradation and Failure Mechanisms of Lithium/LiNixCoyMn1-x-yO2 Batteries
Degradation mechanisms of LiNi0.5Mn0.3Co0.2O2/graphite battery in real-life driving scenarios
Enhancing the Performance and Photostability of Perovskite Solar Cells with a Multifunctional Light-Management Composite
Can Electrochemical Impedance Spectroscopy be Replaced by Direct Current Techniques in Battery Diagnosis?
Featured News
Future makers research batteries, cryptography and plastic recycling
The Technology Industries of Finland Centennial Foundation awarded 3.5 million euros in research funding to eight projects, five from Aalto University.
Prof. Yaolin Xu’s battery research awarded prestigious energy storage prize
Track record and future potential in building better energy storage solutions landed Assistant Professor Xu the Energy Storage Materials Young Scientist Award.