Interfacial study of electron transport in Li-batteries using a microfabricated thin-film model structures

Lithium-ion batteries are a mature technology that powers most of our portable technology. Significant effort is devoted to improving energy density, getting longer life cycle, and having better safety. Lithium-ion batteries are electrochemical systems composed of two electrodes separated by an electrolyte. The electrochemically active material at the electrode exchanges lithium with the electrolyte and the charge is balanced by releasing electrons into the external circuitry. The efficiency of this charge transfer plays a significant role in the performance of the battery. Many research efforts are focused on the interaction between the active material and the electrolyte (lithium transport), however, the transfer of electrons with the current collector is often overlooked.  

In imec, we work with thin-film electrodes as a platform to study in detail these interfaces. Thin films offer control over the interfaces compared with composite electrodes, and it has a wide range of in-situ and ex-situ characterization techniques. Moreover, with the help of lithographic techniques, metals can be patterned on top of the active material and properties such as the contact resistance can be determined.  

In this research topic, the student will fabricate different metals patterned on active material. The work will comprise understanding electron transport in composite electrodes and how thin films can be used as a platform to characterize the interfaces in a battery. The student will learn fundamentals of electrochemistry, hands-on experience with an argon-filled glovebox, lithographic techniques inside the cleanroom, physical vapor deposition systems and characterization tools such as a parameter analyzer, SEM, XRD, etc. The student will work in the Energy Storage and Conversion team in imec, as a part of an interactive research environment. For more information on this topic, please contact Rodrigo.LopezBaez@imec.be.