Lithium microbatteries are developed at LMBE (Laboratory of Micro-Batteries Embedded) in a common laboratory between ST microelectronics and the CEA/LETI/DCOS. Microbatteries consist of a stack of thin films made by Physical Vapor Deposition: current collector, cathode, electrolyte, anode and encapsulation. The whole stack is developed at the laboratory from current collector until encapsulation of the final product. One of the issues for the microbatteries integration in electronic circuits is the decrease of the internal resistance. This issue needed the optimization of the electrolyte performances and the interfaces electrode/electrolyte optimization.

The goal of this PhD is to developed microbatteries with low internal resistance by an action on two points: the ionic conductivity of the electrolyte and the resistance at the interfaces. The work is going to run through two parts: the first is going to focus on the development of new electrolytes with very high ionic conductivity and the second one on the integration of this electrolyte in a microbattery to do a study of the interfaces.

Firstly, the candidate will develop a PVD electrolyte with high performances doing variations of deposition conditions and chemical composition. Physicochemical characterizations like SEM, ICP-MS, XPS… and electrical characterizations like impedance spectroscopy or I(t) will be realized to defined the performances of the new electrolyte.

The best electrolyte will be integrated in microbatteries realized at the laboratory to study the batteries performances and the interfaces electrode/electrolytes. The candidate will characterize the interfaces with electrical measurements correlated to physicochemical interfaces study realized at the nanocharacterization platform of the CEA.

The candidate will have to understand the conduction and interfaces mechanisms in order to propose inovating solutions to optimize the performances.

This position is open until it is filled.

Department: Département Composants Silicium (LETI)
Laboratory: Laboratoire Composants micro stockage de l’Energie
Start Date: 01-10-2015
ECA Code: SL-DRT-15-0147
Contact: lucie.levan-jodin<στο>cea.fr