ChE PhD Dissertation Defense: Eric Zimmerer

Name:
Eric Zimmerer

Title:
Rechargeable alkaline Zn-MnO₂ batteries for grid-scale energy storage

Date:
02/02/2026

Time:
2:00:00 PM

Committee Members:
Prof. Joshua Gallaway (Advisor)
Prof. Hannah Sayre
Lu Ma
Prof. Magda Barecka

Location:
333 Curry Student Center

Abstract:
Grid-scale batteries enable the integration of renewable energy from intermittent sources and level demand on power plants, but recent installations have been almost exclusively lithium-ion. Aqueous batteries, such as the ubiquitous primary alkaline Zn-MnO₂ battery, are free from the flammability, toxicity, and supply chain concerns that surround lithium. Rechargeable alkaline Zn-MnO₂ batteries currently rely on a low depth of discharge (DOD) of both the MnO₂ cathode and Zn anode, however, worsening their economics.

Detailed in this work are developments to the mechanistic understanding and electrochemical performance of rechargeable alkaline MnO₂ cathodes cycling their full capacity of two electrons per Mn atom. During cycling the cathode undergoes intercalation and dissolution-precipitation type reactions involving disordered species, making characterization difficult. Furthermore, MnO₂ cathodes need to be modified with Bi to cycle reversibly, but the mechanism through which Bi makes MnO₂ rechargeable is not well defined.

An interfacial region of disordered β-MnOOH is identified for the first time and found to be stabilized by Bi using operando extended x-ray absorption fine structure (EXAFS) and post-mortem selected area electron diffraction (SAED). Furthermore, irreversible Mn₃O₄ formation is proven not to occur in Bi-modified alkaline MnO₂ electrodes using in-situ Raman spectroscopy and energy dispersive X-ray diffraction (EDXRD). An alternative degradation mechanism is investigated through characterization of Bi-doped MnO₂. Finally, a cell with decoupled catholyte and anolyte is designed to prevent zinc poisoning of the MnO₂ cathode.

Eric Zimmerer is a member of the Analysis of Complex Electrochemical Systems (ACES) lab led by advisor Professor Joshua Gallaway. In February 2026, Eric will defend his Ph.D. thesis on the development of low-cost and sustainable batteries for grid-scale energy storage. While at Northeastern, Eric served as lab safety officer, treasurer for the Graduate Student Council, and a mentor for undergraduate researchers. During his time at Northeastern, Eric specialized in the development and characterization of aqueous battery chemistries. Specifically, he used synchrotron characterization techniques, performed at Brookhaven and Argonne National Laboratories to characterize disordered structures present during battery cycling and to characterize the materials inside of sealed batteries under compression. After graduating, Eric hopes to work in battery research in the San Francisco Bay Area.