Research Projects

This interdisciplinary proposal is aimed at developing an energy dense SSB cell through the processing and integration of (1) composite cathodes incorporating high voltage, morphologically optimized (single/poly-crystal) cobalt-free cathodes (LiNi0.9M0.05Al0.05O2, where M=Mn, Fe, Ti, Mg etc), (2) low temperature processable Li-rich anti-perovskite SE (Li₃OX with X = Cl, Br, or a combination with potential dopants, etc.), (3) ultrathin lithium metal anodes (integrated with Cu foils), and (4) bipolar current collectors (Ti or carbon fiber based) for efficient device assembly to achieve high energy and power densities. The high voltage critical material free NMA class of cathodes in various tailored nano-scale, single crystalline and customized poly-crystalline cathode morphologies with stable Li conducting surface coatings (LiNbO3, metal-inorganic-organic layers, MIOLs, etc.) are specifically targeted to achieve high energy and densities, mechanical and chemical robustness and to overcome the kinetics and transport limitations of SSB cathodes. The anti-perovskite family of solid electrolytes (Li₃OX with X = Cl or Br or a combination of both) famed for their high chemical stabilities, wide electrochemical windows (up to and over 5V), and enhanced ion transport properties in their glassy states coupled with low temperature processability (300 oC melt state) demonstrate properties desirable for ideal solid electrolytes.[4] Additionally, the anti-perovskite structure is also flexible to chemical substitution and modification, allowing for the further enhancement of ionic conductivity/stability (0.001 S/cm at 25 C, comparable to widely studied garnet SE).[5] Furthermore, we expect the Li metal to easily wet the surface of Li3OX thus minimizing interfacial contact resistance resulting in mitigated dendrite growth. Leveraging these unique features, this proposal is aimed at pursuing the development of scalable melt processing protocols that can easily facilitate the infiltration of SE into specifically engineered cathode architectures which can then be readily assembled into SSB cells. For anodes, we would employ ultrathin lithium metal foils (50 µm) obtained through mechanical calendaring/pressing onto copper foils achieving size reduction of commercial lithium metal foils which will also be coated with sputtered/thermally deposited electro-chemo-mechanically stable seeding or interlayers. Additionally, we also aim to implement bipolar stacking architectures enabled by bipolar plates (sputtered/thermally deposition) as current collectors made of titanium or conducting carbon fiber instead of conventional copper and aluminum. Throughout the scope of this effort, we would also employ the unique material and electrochemical characterization techniques (using: X-Ray, XPS, GC-Mass Spec., HR-TEM, etc.) for guiding our scientific decisions through a positive data driven feedback loop.