Recently, a new class of high-energy-density, Li- and Mn-rich layered cathode materials has been discovered. The project aims to build the fundamental knowledge base needed to progress towards design and processing of the materials with desired properties through integrated first-principles calculations, CALPHAD modeling, materials processing, and battery assembling and testing. This fundamental knowledge base also builds the genome foundation to discover new cathode materials. The new cathode material resides in a multi-component space of xLi2MnO3ª(1-x)LiMO2 with M being alloying elements including Mn, Co, and Ni. In the project, first-principles calculations will be used to systematically investigate the effects of these common alloying elements and potential outliers on electronic structures and charge transfers and predict thermodynamic properties of individual phases as a function of temperature and compositions. CALPHAD modeling will be utilized to establish phase relations and optimize the composition space (x and M) for superior charging-discharging performance. To validate the predictions from first-principles calculations and CALPHAD modeling, cathode materials will be synthesized with tailored composition and assemble coin cells to test battery performance. The project objectives are:
1.Establish fundamental understanding of effects of alloying elements and search for potential outliers; 2.Develop a thermodynamic description of the Li-Mn-Co-Ni-O system plus potential outliers; 3.Synthesize and characterize cathode materials and test battery performance based on computational modeling and feedback to improve databases.
Nontechnical Summary
The development of new materials and the capability of tailoring existing materials to meet new and demanding applications are critical for continued improvements in the quality of human life. Materials are a determining factor in the global competitiveness of the U.S. manufacturing industry as materials account for up to half of the costs of most manufactured products. Li-ion rechargeable batteries are the key constituent for low cost and high-energy-density storages needed for numerous applications such as electronic devices and electric vehicles. The development of novel cathodes is critical because of the limitations of cost and energy density for cathodes used in current rechargeable Li-ion batteries. Recently, a new class of high-energy-density, Li- and Mn-rich layered cathode materials has been discovered. The project aims to build the fundamental knowledge base needed to progress towards design and processing of the materials with desired properties through integrated first-principles calculations, thermodynamic modeling, materials processing, and battery assembling and testing. This fundamental knowledge base also builds the genome foundation to discover new cathode materials. The proposal's intellectual merit lies on its collaborative, synergistic approaches between theory, computation, and experiments to rapidly build a chemistry-processing-structure-property-performance knowledge base for the Li- and Mn-rich layered cathode materials. This integrated approach will be based on the combined expertise in simulations, syntheses, and evaluation of battery materials. The research project aims to move the low cost and high-energy-density cathode materials research in the US to a new level by further building the foundation to answer fundamental questions that can only be addressed efficiently via combined computational and experimental methodology. These include: what is the best combination of Li/Mn/M layers in terms of cost and performance? what are the composition/temperature variations for their robust processing? and what are the potential outliers of alloying elements for superior performances? Broader impacts include following aspects, in addition to economic impact of low-cost and high-energy-density cathode materials on battery manufacturing, a) educate students to be professionals mastering both innovative computational and experimental approaches with cross-disciplinary knowledge of materials and batteries; b) encourage students to make presentations at professional meetings to improve communication skills; c) foster students' writing skills through peer reviewed journal publications; d) participate in activities to broaden the participation of underrepresented groups through the SEEMS (Summer Experience in Earth and Mineral Science) programs for high school students and WISER (Women in Science and Engineering Research) program for first year students, e) contribute to new materials research paradigm in shortening the time for developing new materials and improving existing materials to minimize the cost to the society and the negative impact to the environment, and increasing the competitiveness of US manufacturing.
