Understanding charge and mass transport across interfaces and interphases in rechargeable batteries
Robert Kostecki, Lawrence Berkeley National Laboratory, Berkeley, USA
The development of the next generation rechargeable batteries requires a fundamental understanding of the phenomena occurring at the electrode/electrolyte interface during operation. The investigation on the mechanisms governing the function and operation of battery materials, interfaces and interphases, is indissolubly linked to the successful obtainment of long life and high performance electrochemical energy stoarge systems. Interfacial reactions, which include lithium ion insertion/extraction, decomposition of the electrolyte and formation of a solid electrolyte interphase (SEI) layer determine the irreversible capacity, cycling ability and lifetime of batteries.
The chemical composition and functional mechanisms of the SEI are not well understood, due to the non-homogeneous properties of composite electrodes and the technical barriers associated with characterization methodologies across length and temporal scales that correspond to the SEI basic components and their function. Unraveling the basic function and operation of electrodes and electrode/electrolyte interfaces at the length-scale that corresponds to its basic building blocks is essential to guide development of high-energy rechargeable batteries. This work describes characterization of active materials and composite electrodes as well as studies of the properties of the individual components and their interfaces at the length-scale that corresponds to their basic building blocks. We leverage the use of model experimental systems and novel near-field optical characterization techniques to investigate and evaluate intrinsic properties of individual components such as additives and advanced binders and their effects on the composite electrodes electrochemical performance.