Description of the thesis topic

Li-ion batteries (LIBs), one of the major advancement in the history of technology is widely in use for various applications such as portable electronics, electric vehicles as well as stationary energy storage. However, the limited lithium resources in the earth crust necessitate the search for alternate energy storage technologies for backing up with Li-ion batteries. Though prototype Na-ion batteries are demonstrated by several start-up companies, the maturation of technology is not reached yet due to lack of optimized electrode and electrolyte materials. In order to answer this issue, the current thesis work will focus on developing new electrode materials for Na-ion battery applications. The electrode materials for study will be selected from oxide, fluorides, oxy-fluorides and sulfides. The phase pure material will be synthesized using different synthetic methods and their chemical/ electrochemical properties will be evaluated. The optimized electrode materials will then be evaluated for their electrochemical performance in Na-ion batteries by combining them with different electrolyte formulations. Studying the interfacial reaction between the developed electrode and electrolyte is one of the major requirements for transferring the lab scale knowledge to real applications. So, equal importance will be given to study the interfacial reactions and optimize the electrolyte for the developed electrode materials.
A multi-disciplinary profile with notions of materials science and electrochemistry would be welcome as well as fluency in English.

Work Context

Syntheses of inorganic materials using different synthesis method need to be carried out. The phase purity of the synthesized the material will be analyzed and complete structural evolution will be carried out using Rietveld refinement of XRD and neutron powder diffraction patterns when required. Electrochemical analyses will be carried out in Na-half cells as well as Na-ion full cells. The experiments will be done by varying the electrolyte formulations. The possible transition metal dissolutions during electrochemical reactions will be followed by ICP analyses. The materials will also be tested for their thermal stability while being in contact with the electrolyte under study. The study will be extended to prototype 18650 cells with the optimized electrode- electrolyte combinations.

The position is located in a sector under the protection of scientific and technical potential (PPST), and therefore requires, in accordance with the regulations, that your arrival is authorized by the competent authority of the MESR.

Constraints and risks

N/A