PhD in In-Operando Diagnostics of Li-ion and Post-Li-ion Batteries Using Acoustic Technology

Det Ingeniør- og Naturvidenskabelige Fakultet, Institut for Energi; Aalborg; On-site; DKK 312,000 - 357,000; Full time

Job summary

AAU Energy in Aalborg invites applications for a PhD stipend in In-Operando Diagnostics of Li-ion and Post-Li-ion Batteries Using Acoustic Technology. The three-year position starts 15 November 2026 or soon after and is hosted within the Batteries research group.

You will study acoustic-based diagnostics, design a coin-cell sensing setup, perform degradation tests with simultaneous acoustic and electrical measurements, and develop a physics-validated model.

Qualifications

• PhD candidates hold a Master’s degree in a relevant field.
• Experience with electrical characterization of batteries, acoustic sensing, and laboratory instrumentation will be advantageous.
• Strong English communication skills are required; Danish is desirable but not required for supervision duties.
• Willingness to supervise BSc/MSc projects and contribute to teaching will be expected.

Responsibilities

• Review the state of the art in acoustic-based battery diagnostics.
• Design and build a coin-cell acoustic sensing setup.
• Perform degradation tests with simultaneous acoustic and electrical measurements.
• Develop a physics-validated acoustic-based diagnostic model; aim for higher accuracy and efficiency.
• Contribute to teaching, supervision of students, and dissemination activities within the department.

Skills

Electrical characterization of battery

Acoustic/ultrasonic sensing

Laboratory instrumentation

Signal processing & modelling

Problem Based Learning (PBL)

English communication

Education

Master's degree in electrical engineering, energy engineering or mechatronics

Tools

MATLAB

Python

Job description

PhD in In-Operando Diagnostics of Li-ion and Post-Li-ion Batteries Using Acoustic Technology

At AAU Energy, a PhD stipend position is available within the general study program. The stipend is open for appointment from 15 November 2026 or soon hereafter. The duration of the position is three years.

Your work tasks

Battery performance assessment and diagnostics rely today on standardised electrical measurements complemented by post-mortem analysis. None of these methods is suited for in-operando diagnostics, as they are either destructive or require the battery to be taken out of its daily operation. Acoustic techniques, based either on passive listening to acoustic emissions or on active ultrasound signal injection, have recently been proposed as an alternative; however, further research is needed to establish the relationship between materials degradation and the sensed acoustic signals. The aim of this PhD project is to establish a mechanistic understanding of the coupling between battery ageing mechanisms and measured acoustic signals, and to translate this understanding into a diagnostic method applicable to both Li-ion and post-Li-ion chemistries.

You will start by reviewing the state of the art in acoustic-based battery diagnostics, and you will then design and build a set-up for sensing acoustic emissions in coin cells. Using this set-up, you will carry out degradation tests over a wide range of operating conditions with simultaneous acoustic and electrical measurements, and you will analyse how the acoustic signatures relate to the electrical ones and to the underlying degradation mechanisms. On this basis, you will develop an acoustic-based, physics-validated model for battery diagnostics; the resulting algorithm is targeted to be at least 25% more accurate than conventional impedance-based estimation and at least 50% less energy demanding than traditional diagnostic approaches. While most of the experimental work will be carried out at coin-cell level, a proof of concept at single-layer pouch-cell level is expected, which will facilitate further demonstration towards innovation.

The work will be supported by critical analysis of the results, benchmarking against the state of the art, and high-quality publications and conference presentations. In addition to the research activities, you will contribute to teaching and to the supervision of student projects, as well as to broader dissemination activities within the department.

The position is offered in relation to the research group Batteries, and the PhD Student will be positioned to the section for Power Electronics Systems Integration and Materials.

Your competencies

We are looking for a motivated PhD candidate who is eager to work at the intersection of battery testing, sensing instrumentation and signal processing, and who enjoys combining fundamental understanding with hands‑on experimental work. The ideal candidate is curious and persistent in the laboratory, excels at troubleshooting, can plan and execute experiments independently, and motivated to collaborate closely with colleagues in an international and interdisciplinary environment.

Applicants must hold an M.Sc. degree in electrical engineering, energy engineering or mechatronics. Experience with one or more of the following will be considered an advantage: electrical characterisation of batteries, acoustic or ultrasonic sensing and laboratory instrumentation, and signal processing and data‑driven modelling (e.g., in MATLAB or Python). Experience with Problem Based Learning (PBL) is required, as the PhD student will be involved in the supervision of BSc and MSc student projects. Strong communication skills in English, both written and spoken, are required, as the project will be carried out in an international research environment. Danish language skills are highly desirable and will support co‑supervision of BSc student projects; however, they are not a formal requirement.

Qualification requirements

PhD stipends are allocated to individuals who hold a Master's degree. PhD stipends are normally for a period of 3 years. It is a prerequisite for allocation of the stipend that the candidate will be enrolled as a PhD student at the Doctoral School of Engineering and Science in accordance with the regulations of Ministerial Order No. 1124 of September 19, 2025 on the PhD Programme at the Universities and Certain Higher Artistic Educational Institutions. According to the Ministerial Order, the progress of the PhD student shall be assessed at regular points in time. As part of the PhD study, you are among other things required to complete PhD courses corresponding to 30 ECTS, gain experience with teaching or other forms of knowledge dissemination and complete an external research stay outside of Aalborg University, preferably 3-6 months at a foreign research institution.

Who we are

AAU Energy is a research department at Aalborg University dedicated to the development of clean and sustainable energy systems. Our activities cover electrical, thermal and mechatronic energy technologies, and we work closely with industrial partners, utilities and other academic environments to address real world energy challenges.

Aalborg University has been ranked as the best university in Europe within energy research and is among the very best universities worldwide in this field. At AAU Energy you will be part of a top international environment where research, innovation and collaboration are used to develop solutions to global challenges such as the green transition and future energy systems.

The department is located in both Aalborg and Esbjerg, and this position is based at the Aalborg campus. AAU Energy employs around 250 staff members at different career stages and with diverse national and disciplinary backgrounds, which creates an international and interdisciplinary research environment with many opportunities for collaboration and knowledge sharing. English is widely used as working language in both research and teaching, which supports the integration of international colleagues.

We offer access to advanced laboratory and workshop facilities and an environment where you can develop your academic profile through research, teaching and collaboration with both Danish and international external partners. As a workplace we value a collegial and inclusive culture with room for professional discussion, initiative and mutual support in everyday work.

New colleagues, whether they come from elsewhere in Denmark or from abroad, can draw on the university’s support services related to relocation, housing and practical matters. Aalborg University offers general onboarding support to all new employees, as well as dedicated support for international staff through its International Staff Unit (ISU). You can read more about relocation support and services here: https://www.en.hr.aau.dk/relocation-support

Aalborg University also offers Danish language courses to support international employees in settling into both the workplace and Danish society. International employees typically can attend Danish language courses during their first years in Denmark (depending on individual eligibility and national schemes).

Aalborg University wants to reflect the surrounding society and has diversity as a core value. Therefore, everyone, regardless of personal background and orientation, is encouraged to apply for the position.

Do you have any questions?

If you have any questions about the position, you are more than welcome to contact us. You will find contact persons at the bottom of the jobpost.

Further information
Read more about our recruitment process here.

The assessment of candidates for the position will be carried out by qualified experts.
Shortlisting will be applied. This means that after the application deadline, the head of the department, with the assistance of the hiring committee, will select the applicants to be assessed. All applicants will be informed whether they have been shortlisted for assessment or not.

The hiring process at Aalborg University may include a risk assessment as a tool to identify potential risks associated with new hires, ensuring the safety, compliance, and integrity of the workplace.

Salary and terms of employment
The employment is in accordance with the Ministerial Order on the Appointment of Academic Staff at Universities and the Ministerial Order on Job Structure for Academic Staff at Universities. Furthermore, your terms of employment and salary are in accordance with the collective agreement between the Danish Confederation of Professional Associations and the state (AC collective agreement).

There is a mutual probationary period of 3 months for the position.

Aalborg University - Knowledge for the world

Type of employment

Type of employment Temporary position more than 6 months

Contract type

Contract type Full time

Number of positions

Number of positions 1

Full-time equivalent 37

City

City Aalborg

County *

Country

Reference number

Reference number 2026/1212

Contact

• Daniel-Ioan Stroe, [phone], [e-mail]