Li-ion batteries (LIBs) are ubiquitous, used as energy storage devices in portable electronics and electrical vehicles. Increasing the energy density of these batteries is necessary to allow for longer runtime of cell phones and the increased range of electrical vehicles. Critical to increasing the energy density of LIBs is enabling high-voltage charging of current LIB cathodes. This effort is hindered by the rapid capacity fading over charge-discharge cycles caused by parasitic reactions between the cathode and the electrolyte that also undermine the battery’s safety. One effective strategy to overcome this problem is to coat the cathode surface with a chemically inert material as a barrier to prevent the parasitic reactions from occurring. The goal of this project is to understand the functionality of the surface coating to enable high-voltage cathodes for high energy density LIBs. This research will address a major challenge in the advancement of LIBs. To broaden the participation in STEM, an art-science partnership will be implemented to connect scientific advances to real-world applications. This will be implemented in the existing First-year Research Immersion and the NSF Research Experience for Undergraduates programs at Binghamton University. This research will also offer workforce training opportunities for students to gain proficiency in manufacturing-level battery assembly.
Commercialized Li-ion battery technologies are reliant on Ni-rich layered oxide cathodes to achieve the high energy density and power output required for today’s applications (electric vehicles, grid storage, etc.). Coating layers have been widely employed as engineering solutions to improve the performance and reliability of these oxide cathodes, yet their underlying functionality during cycling remains unclear. This project addresses aluminum oxide coatings (Al2O3 and LiAlO2) and their impact on Li-ion transport, cathode-electrolyte interface stability, and cycling performance for two systems: high quality LiCoO2 thin films and commercial LiNi0.8Mn0.1Co0.1O2 (NMC 811) micron-sized particles. Atomic and chemical X-ray spectroscopic and diffraction characterization will be connected to ab initio molecular dynamics simulations to directly identify the extent to which detrimental degradation pathways, e.g. particle cracking, oxygen loss, and transition metal reduction, are avoided with the use of aluminum coatings. The research will provide insight into atomic level processes in order to guide the development of robust coating layers that can be scaled up into manufacturing-grade testing.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
