Post-Doctoral position: Intermediate temperature sodium sulphur battery for residential energy storage - NaSTOR prototype

DIFFER (Dutch Institute for Fundamental Energy Research) is one of the Netherlands Organisation for Scientific Research (NWO) institutes and focuses on a multidisciplinary approach to energy research, combining physics, chemistry, engineering and materials science. The institute is based on two main strands, solar fuels for the conversion and storage of renewable energy and fusion-energy as clean and unlimited source of energy. DIFFER is developing and supporting a national network on fundamental energy research and is closely collaborating with academic institutions, research institutes and industry.

Post-Doctoral position: Intermediate temperature sodium sulphur battery for residential energy storage - NaSTOR prototype

Through a joint collaboration Exergy Storage (SME) and DIFFER aim with a consortium of partners to realize a prototype battery operating in this intermediate temperature window suitable for residential storage unit through the project NaSTOR. In this context, the role of DIFFER is particularly to focus on the challenges related with the NaSBs cathodic compartment. Therefore a postdoctoral position is available in the DIFFER group, Catalysis and electrochemical processes for energy applications, for investigating the effect of catholyte composition and refreshment on the efficiency and stability during charge-discharge cycles.

Scientific aim: 

Energy storage concepts will be increasingly used in the near future as a result of increased implementation of renewable energy sources in energy infrastructure. In this aspect, batteries are considered as suitable candidates for compensating the intermittency of the renewable sources like solar and wind energy. Sodium-sulphur batteries (NaSBs), are considered as potential energy storage systems for stationary electric storage applications. The main advantages of NaSBs  are the high energy density, high efficiency of charge/discharge, long cycle life, and that they are fabricated from abundant and low cost materials. NaSBs batteries employ sodium (Na) and sulphur (S) as active electrode materials, and beta-alumina (Al2O3) ceramic membranes as the Na+-conducting electrolyte. Traditional NaSBs operate at high temperatures of 300-350 oC, where both of the electrodes are in a molten state for having the optimum electrochemical reactivity, and for the beta-alumina membranes to have the optimum ionic conductivity. However, safety issues related with high temperature operation triggered novel NaSBs battery concepts, which aims at operating temperatures just above the melting point of sodium (i.e. 120-150 oC). These operating conditions introduce challenges that need to be addressed for optimizing the new NaSBs.

Responsibilities and tasks: 
  • Cathode formulations characterization with suitable electrochemical methods and operando Raman spectroscopy
  • Support development of optimal cathode formulation for NaSTOR battery:
    • Investigation of performance limiting mechanisms (e.g. transport phenomena, liquid-solid phase transformations etc.)
    • Determination of operating windows, phase diagrams
  • Part-time involved in testing in Exergy’s laboratory in Arnhem.
  • Prepare scientific papers and conference communications.
  • Contribute to the scientific and collaborative research environment at DIFFER.

We seek enthusiastic candidates with a proven can-do attitude, coming up with practical working solutions is a must. The candidates has experience in electrochemical characterization techniques such as cyclic voltammetry, electrochemical impedance spectroscopy (with equivalent circuit modeling) and other diagnostic tools to improve performance. The candidates should have a PhD degree in electrochemistry or chemical engineering. Good verbal and written communication skills (in English) are mandatory. The successful candidate should have demonstrated expertise in batteries research. Experience with Raman spectroscopy is a plus.

Employment conditions: 

Our institute offers a first class and international research environment with various interdisciplinary but related research topics and projects. You will be employed by the NWO institute Foundation for a fixed period of 1.5 years. Your salary will be up to a maximum of 4,154 Euro gross per month, depending on your level of experience. The salary is supplemented with a holiday allowance of 8 percent and an end-of-year bonus of 8.33 percent. NWO and DIFFER have number of regulations that support employees in finding a good work-life balance. Such as conditions for teleworking, partly paid parental leave and the possibility to purchase and sell holiday leave. General information on working at NWO can also be found at the NWO website (

The position will be based at DIFFER - the Dutch Institute for Fundamental Energy Research ( and the working locations will be at TU Eindhoven and (part-time) at the Industry Park IPKW in Arnhem.

Further information: 

The 'NWO job interview code' applies to this position. DIFFER strives to achieve a diverse workforce to develop talent and creativity by bringing together different perspectives. As such we encourage applications from women and minorities. Further information on the vacancy is available through, Dr M. Tsampas, e-mail: m [368] tsampas [28] differ [368] nl and CEPEA website For information on the NaSTOR development please contact: Dr. Gert Jan Jongerden, gertjan [368] jongerden [28] exergy-storage [368] nl

Application procedure: 

In case you are interested you can apply by submitting an application letter, a grade list and full resume. Please refer to vacancy 17.015. The letter of application and other documents may be sent electronically as single PDF-files (in the following format lastname_appl.letter, lastname_CV, etc), to vacancies [28] differ [368] nl .

Closing date: 
Saturday, December 15, 2018
Vacacany number: