Engineering Solid-State Electrochemical Devices: From Void Suppression to Microstructure & Interphase Control (21/09/26)
Speaker and Affliation:
Dr. Vikalp Raj
Postdoctoral Research Associate at Oak Ridge National Laboratory
When?
21st September, 2026 (Monday), 03.00 PM (India Standard Time)
Where
KPA Auditorium, Dept. of Materials Engineering, IISc, Bangalore
Abstract:
Solid-state batteries with lithium metal anodes promise higher energy density and safety, but dendrite growth remains the key barrier. In garnet LLZTO, we found voids form before dendrites, even below critical currents, and that metallic interlayers can delay dendrites by addressing the root causes of void growth (Nat. Mater. 2022, 21, 1050). Dendrites preferentially propagate along grain boundaries in small-grain regions; comparing conventional versus high-energy milled microstructures (Adv. Energy Mater. 2024, 2303062). A two-phase microstructure, in which reactive TaC drove grain-boundary precipitation of amorphous ZrO2, improved toughness, and density, while cryogenic FIB-SEM revealed previously unseen transgranular propagation (Nat. Mater. 2026, 25, 249). Extending this to sulfide argyrodite (LPSCl), where interphase instability governs failure, an anode-free electrode hosts two distinct SEIs that must both be controlled; tailoring them improved efficiency and cycling without excess lithium (Adv. Mater. 2025, 2410948). Together these establish a unifying framework, void suppression, microstructural toughening, and interphase control across solid electrolytes.
Speaker Bio:
Dr. Vikalp Raj is a Postdoctoral Research Associate at Oak Ridge National Laboratory, leading research on Energy storage. He earned his Ph.D. (2022) and M.S. from the Indian Institute of Science, Bangalore. His work centers on solid-state electrochemical interfaces: interfacial failure mechanisms, fracture mechanics of ceramic electrolytes, and microstructure engineering. During his doctorate he linked void formation to dendrite growth in garnet electrolytes; as a postdoc at UT Austin, he worked on microstructure engineering of LLZTO and extended this to argyrodite and anode-free architectures. Currently at ORNL, he is working on Zinc batteries and electrocatalysts.