NANOTECH LAB | YUSHIN GROUP

Transforming the energy materials landscape from the nanoscale to the macro

Our research group focuses on finding nanotechnology-driven solutions to enable the next generation of lighter, more energy dense, more cost effective energy storage devices by studying their materials structure-property relationships. We have developed nano-scale synthesis strategies to bypass macro-scale limitations of energy and structural materials with applications in clean tech, electric vehicles, wearable electronics, and more.

Publications

Scalable, safe, high-rate supercapacitor separators based on the Al2O3 nanowire Polyvinyl butyral nonwoven membranes

2020

Nano Energy

Mengting Liu, Kostiantyn Turcheniuk, Wenbin Fu, Yang Yang, Michael Liu, Gleb Yushin

High-performance supercapacitor nonwoven separators based on polyvinyl butyral (PVB) with uniformly distributed Al2O3 nanowires (NW) fillers (up to 40 wt %) have been developed using a low-cost casting (stir-pour-dry) technique utilized under ambient conditions for the first time. These novel nonwoven separators with highly porous network demonstrated tensile strength of >30 MPa, extremely high electrolyte absorption (>200 wt. %), low-to-no swelling behavior and stable electrochemical performance, substantially exceeding that of analogous cells with commercial separators. Thermal properties of the produced separators were also exceptional with >15 MPa of ultimate strength, high flexibility and minimal thermal shrinkage maintained at temperatures as high as 200 °C. The one-dimensional (1D) ceramic nanofillers improved PVB's mechanical and thermal properties and enabled formation of highly porous membranes with self-organized nanopores and high ionic conductivity of up to 13.5 mS/cm in 1 M Na2SO4 aqueous electrolyte. This simple and innovative method and separator design is attractive for manufacturing of high-strength, low-cost and flexible separators and suitable for various polymers-ceramic nonwoven compositions for fast charging, high-power and safe electrochemical capacitors, hybrid devices and batteries.

Understanding Li‐Ion Dynamics in Lithium Hydroxychloride (Li2OHCl) Solid State Electrolyte via Addressing the Role of Protons

2020

Advanced Energy Materials

Ah‐Young Song, Kostiantyn Turcheniuk, Johannes Leisen, Yiran Xiao, Lamartine Meda, Oleg Borodin, Gleb Yushin

Low‐melting‐point solid‐state electrolytes (SSE) are critically important for low‐cost manufacturing of all‐solid‐state batteries. Lithium hydroxychloride (Li2OHCl) is a promising material within the SSE domain due to its low melting point (mp < 300 °C), cheap ingredients (Li, H, O, and Cl), and rapid synthesis. Another unique feature of this compound is the presence of Li vacancies and rotating hydroxyl groups which promote Li‐ion diffusion, yet the role of the protons in the ion transport remains poorly understood. To examine lithium and proton dynamics, a set of solid‐state NMR experiments are conducted, such as magic‐angle spinning 7Li NMR, static 7Li and 1H NMR, and spin‐lattice T1(7Li)/T1(1H) relaxation experiments. It is determined that only Li+ contributes to long‐range ion transport, while H+ dynamics is constrained to an incomplete isotropic rotation of the OH group. The results uncover detailed mechanistic understanding of the ion transport in Li2OHCl. It is shown that two distinct phases of ionic motions appear at low and elevated temperatures, and that the rotation of the OH group controls Li+ and H+ dynamics in both phases. The model based on the NMR experiments is fully consistent with crystallographic information, ionic conductivity measurements, and Born–Oppenheimer molecular dynamic simulations.

Collaborators

Some of the Institutions we’ve collaborated in the past. For collaboration inquiries, contact Professor Gleb Yushin.

Central South University
Xavier University of Louisiana
Technische Universität Dresden
Spanish National Research Council

Contact Us

Get in touch! Send an email to Professor Yushin at yushin@gatech.edu.