Graduate Student at CCNY Defends Ph.D. Dissertation

On Thursday, May 9, 2024, Jungsang Cho, a graduate student at the City College of New York (CCNY), under the tutelage of Professor Sanjoy Banerjee, successfully defended his Ph.D. dissertation titled “Understanding the Application of Hydrogel Electrolytes for Rechargeable Alkaline Zinc-Manganese Dioxide Batteries.” Cho’s thesis work was the result of a collaborative effort with Sandia National Laboratories’ Energy Storage Program, specifically a project on Advanced Zn Batteries (PI: Sandian Timothy N. Lambert). The goal of this research is to advance Zn-based batteries for grid and long duration energy storage applications.

Zinc (Zn)–manganese dioxide (MnO2) rechargeable batteries have high specific theoretical capacity, are environmentally friendly, intrinsically safe, and low-cost. Liquid electrolytes, such as potassium hydroxide, are historically used in these batteries; however, many failure mechanisms of the Zn–MnO2 battery chemistry result from the use of liquid electrolytes, including the formation of electrochemically inert phases on the MnO2 cathodes and shape change of the Zn anode.

This thesis details the development and use of polymer gel electrolytes to mitigate many of the failure mechanisms for Zn-MnO2. Improved Zn-MnO2 cells are demonstrated for both the 1-electron and 2-electron regimes for MnO2, whereby cells utilizing the gel electrolyte showed higher capacity retention compared to the tests with the liquid electrolyte. Improved cell safety was also achieved as the hydrogels are ‘non-spillable’, according to standards from the US Department of Transportation.

This material is based upon work supported by the U.S. Department of Energy, Office of Electricity (OE), Energy Storage Division.

J. Cho, G.G. Yadav, M. Weiner, J. Huang, A. Upreti, X. Wei, R. Yakobov, B. Hawkins, M. Nyce, T.N. Lambert, D.J. Arnot, N.S. Bell, N.B. Schorr, D. Turney, G. Cowles, S. Banerjee “Hydroxyl Conducting Hydrogels Enable Low-Maintenance Commercially Sized Rechargeable Zn-MnO2 Batteries for Use in Solar Microgrids” Polymer 2022, 14 (3), 417. DOI: 10.3390/polym140304417.

J. Cho, D.E. Turney, G.G. Yadav, M. Nyce, B.R. Waygant, T.N. Lambert, S. Banerjee “Use of Hydrogel Electrolyte in Zn-MnO2 Rechargeable Batteries: Characterization of Safety, Performance, and Cu2+ Ion Diffusion” Polymer 2024, 16(5), 658,

G. G. Yadav, M. Sammy, J. Cho, M. Booth, M. Nyce, J. Huang, T. N. Lambert, D. Turney, X. Wei, S. Banerjee “A Report on the Performance of Low Cost and Highly Energy Dense Hybrid Zinc|Manganese Dioxide-Copper Scaled-Cells” Batteries 2024 manuscript under review.