Increasing interest in renewable energy technologies has recently brought compact and cost-effective energy storage into the spotlight. A wide variety of applications could benefit from an appropriate high-energy storage medium capable of efficiently collecting and releasing electrical energy. In this work, the lithium metal battery is introduced as one of the most exciting candidates with the potential to fill this need. In chapter one, today's leading battery solution is explored and compared to the lithium metal cell, and challenges to cycle and calendar life in each system are explained. In particular, the advantages and limitations of the state-of-the-art Li-ion chemistry, including its graphite-based negative electrode, are discussed. Specific challenges to the implementation of metallic lithium - the negative electrode with the highest possible specific energy - are also presented, with the pervasive growth of catastrophic lithium dendrites being the most significant obstacle to its success. An active body of investigation into the formation of these dendritic microstructures in lithium metal cells and various strategies toward eliminating them are introduced. Finally, with support from recent research, we propose that the hard-soft, nanostructured block copolymer electrolyte, poly(styrene-block-ethylene oxide), (PS-b-PEO), represents a fundamentally new approach toward stopping lithium dendrite failure and, in so doing, realizing a metallic lithium anode as part of a stable higher-energy rechargeable battery.

The second chapter presents a complete set of fundamental transport measurements on the solid electrolyte, PS-b-PEO containing the lithium bis(trifluoromethane)sulfonimide (LiTFSI) salt. The LiTFSI mutual diffusion coefficient, measured by restricted diffusion in symmetric lithium cells, is reported along with the ionic conductivity, measured by potentioelectrochemical impedance spectroscopy, for a wide range of salt concentrations at 80 °C. A comparison between these results and those for the homopolymer-PEO system are also discussed. In addition, a straightforward approach toward measuring the lithium transference number in solid electrolyte samples is reported and compared to various existing methods. The transference measurement reported herein depends on an experimental determination of the limiting current, which is undertaken for a range of salt concentrations, also in lithium symmetric cells at 80 °C.

In the third chapter, the focus turns to practical batteries containing lithium metal as a negative electrode and lithium iron phosphate (LiFePO4) as a positive electrode. An extensive electrochemical characterization on batteries with these electrodes and the solid electrolyte PS-b-PEO containing LiTFSI is first reported. In cells with high specific energy, exceptional electrochemical and high-temperature stability is demonstrated over months of repeated charge and discharge cycling. Data collected at charge/discharge rates in the appropriate range for electric vehicle applications (i.e., C/2, which is defined as the current necessary to fully charge or discharge a cell in 2 hours) are compared to data collected on comparable homopolymer-based cells. In order to project ultimate cycle and calendar life limitations, coulombic and energy efficiency measurements are taken for each system, and electron micrographs demonstrate the unprecedented reversibility of the metallic lithium electrochemical reaction in all-solid-state batteries containing the block copolymer electrolyte.

Finally, chapter four describes high-resolution in situ concentration mapping of dissolved LiTFSI in working lithium symmetric cells containing the same block copolymer electrolyte. By synchrotron scanning transmission X-ray microscopy (STXM), performed on all-solid-state batteries, real-time ion composition data, generated by quantitative X-ray absorption measurements, are reported under galvanostatic charge and discharge conditions. In particular, nanometer-resolution fluorine 1s absorbance data within working batteries are converted to Li+ concentration maps to elucidate the evolution of ion composition changes in cells during cycling. Furthermore, a general approach toward accurate, in situ, fundamental transport measurements, including a representative measurement of the lithium transference number for LiTFSI in PS-b-PEO, is reported. We believe this technique represents a seminal effort toward a general method of in situ, nanoscale, soft-X-ray characterization of lithium-based batteries that can be extended to the investigation of other electrolytes as well as to a wide variety of electrode materials for electrochemical systems of all types.

Art of Analysis (AoA) is a cooperative effort of the Ohio State University College of Medicine (OSUCOM) and Columbus Museum of Art (CMA) aimed at medical students who are participating in learning communities, groups formed in pre-clinical medical student education to emotionally support and encourage students through the arduous process of medical training, to develop critical thinking skills; engender empathy; increase tolerance for ambiguity; build team problem solving abilities; and consider multiple perspectives through the observation of artwork. While several medical education institutions in the past have described similar programs, AoA uses a unique critical thinking strategy called “ODIP” (Observe, Describe, Interpret, Prove). Group participants include medical students, the learning community faculty (faculty members from OSUCOM) and CMA educators who facilitate and direct the AoA program. The groups set expectations before the program, emphasizing the goals and objectives of the program. Students then use the ODIP strategy to interpret one work of art as a group before they individually venture into the galleries to find artwork that answers a question posed by facilitators. Students present their theories and defend these ideas in a group discussion format during the two-hour program. The formalized ODIP process provides a framework for students to express their ideas, and by utilizing learning communities create an opportunity for openness and discussion that may not exist between new acquaintances participating in the AoA program de novo. The ODIP strategy is not unique to the AoA program but has been developed by CMA in its efforts to aid critical and personal interpretations of artwork. It is designed to apply to various learners, and is easily applicable to the adult-style learners with varying backgrounds unique to medical training. It is the goal of the AoA program to create abilities in teamwork, tolerance of alternate ideas, an empathy particular to the visual arts, and critical thinking skills. Correlation between the AoA program and ODIP format can easily be made with medical rounds and the process of developing a differential diagnosis as healthcare continues to transition into a more inclusive, multi-disciplinary team approach to health and disease prevention. The AoA program at CMA serves as an important tool in the education of physicians at OSUCOM, helping in the development of skills essential to the clinical practice of medicine.