News

New paper in Angewandte Chemie International Edition: “Synthesis of Ladder and Flexible Polysulfonimides Directly From Anionic Monomers: Investigating Structure–Property Convergence in Succinonitrile–Polymer Electrolyte Blends” (Herzog-Arbeitman, Leon, Schreib, KyuJung Jun, et al.). DOI

Junho Lim started his Ph.D. in the College of Chemistry at UC Berkeley (Bingqing Cheng group). He worked with us as a visiting student on machine-learning potentials for ion transport in amorphous oxyhalide electrolytes.

Doheon Yeom (B.S. student, School of Smart Mobility) joined the group as an undergraduate researcher.

Oral presentation at the Korean Society of Industrial and Engineering Chemistry 2026 Spring Meeting (Jeju): “Understanding and designing ion conductors via machine learning”.

Oral presentation at the Korean Institute of Metals and Materials 2026 Spring Meeting (Jeju): “Developing universal algorithms for decomposing ionic transport into interpretable mechanisms”.

Junho Lim joined the group as a visiting student.

Hyeon-jong Lee (Ph.D. student, KAIST Department of Materials Science and Engineering) joined the group as an exchange Ph.D. student.

KyuJung Jun joined Korea University as an Assistant Professor in the School of Mechanical Engineering and the School of Smart Mobility, and started MINDS Lab. We are recruiting M.S./Ph.D. students, undergraduate researchers, and postdocs (Recruiting).

New preprint: “Universal Framework for Decomposing Ionic Transport into Interpretable Mechanisms” (Jun, Leon, Ruža, Nam, Gómez-Bombarelli), arXiv:2602.16636.

I will be attending ACS 2025 Spring at San Diego! At this conference, I will be giving a talk on “Quantifying transport mechanisms in molecular dynamics simulations of electrolytes via event detection algorithms” in Synthesis & Characterization of Novel Liquid Electrolytes for Rechargeable Batteries session on March 26th, 2025.

Excited to share our latest work published in Matter! 🚀

“Exploring the soft cradle effect and ionic transport mechanisms in the LiMXCl₄ superionic conductor family”

https://lnkd.in/gHRrjzme

In this study, we investigate the crystalline LiMXCl₄ (M = Nb, Ta) oxychloride family—lithium superionic conductors that recently demonstrated an impressive Li-ion conductivity of 12.4 mS/cm at room temperature. But how much higher can we push the conductivity in this framework? And what fundamental mechanisms drive such rapid ion transport?

💡 Key findings:

1. Enhancing stability without compromising conductivity – By tuning cation (M) and anion (X) substitutions, we predict that fluoro-chlorides can offer improved electrochemical stability while maintaining high ionic conductivity.

2. Pushing conductivity beyond 100 mS/cm – Our analysis shows that the LiMXCl₄ framework can be optimized to achieve conductivities up to 100 mS/cm. Compared to close-packed chlorides and LaCl₃ frameworks, its higher Meyer-Neldel energy provides a clear advantage, enabling even greater conductivity and positioning LiMXCl₄ as a strong catholyte candidate for all-solid-state batteries.

3. Revealing the “soft cradle effect” – The LiMXCl₄ structures feature a unique 1D chain of octahedra, bound together by weak van der Waals interactions. Our analysis shows that the small-angle tilting motion of these octahedra is often temporally and spatially coupled with Li-ion hops. This behavior is similar to previously studied materials such as Li₃PS₄ and Li₂SO₄, where the isolated PS₄ or SO₄ tetrahedra tilt in response to nearby Li hops, providing additional degrees of freedom to stabilize migration pathways.

It was a great pleasure to work with Grace Wei on this paper. Also thanks to Xiaochen Yang and Yu Chen for their experimental efforts and Gerbrand Ceder for his invaluable support on this project. Looking forward to further experimental exploration of these oxychlorides as potential catholytes!

Excited to have led the computational search for sacrificial cathode additives to tackle the high irreversible capacity in the first cycle of Si-based anodes! This co-first-authored paper is published today at Advanced Energy Materials. Among the candidates, we take a deeper dive into the antifluorite-structured Li6MnO4 among the candidates. Thank you to all the coauthors and especially Haegyeom Kim for leading this work!

At MRS 2024 Fall in Boston, I am participating in the “Meet the Faculty Candidates” poster session! Feel free to drop by to discuss about my research vision.

Excited to share our review article, “Diffusion Mechanisms of Fast Lithium-Ion Conductors,” which is now published in Nature Reviews Materials!

What is it about these rare, specific crystal structures like argyrodites, NASICONs, or garnets that makes them fast Li-ion conductors? It’s a question I’ve been asking for the past years. Over the last decade, the solid electrolyte community has together gained a much deeper understanding of the factors that govern fast lithium-ion diffusion in inorganic crystal structures and has greatly expanded the chemical and structural diversity of lithium superionic conductors for use in all-solid-state batteries.

In this review, we explore the structural and chemical factors that drive fast lithium-ion diffusion, including perspectives from my own PhD research, to provide a comprehensive understanding of this evolving field. From these insights, we distill the development history of ionic conductors over the last several decades, laying out the key concepts that have paved the way for today’s state-of-the-art superionic conductors. The diversity of design principles for achieving superionic conduction suggests there is still huge potential for experimental and theoretical efforts to design new fast Li-ion conductors for all-solid-state batteries.

A big thank you to Professor Gerbrand Ceder for guiding this work, and to Yu Chen, Grace Wei, and Xiaochen Yang for working together on this paper. I hope our review paper will spark new ideas to improve superionic conductors for all-solid-state batteries!

KyuJung starts postdoctoral position at MIT DMSE to work with Prof. Rafael Gómez-Bombarelli. I will be expanding my research to explore polymer-based Li-ion conductors, design of molecular systems for organic-based flow batteries, as well as machine-learning-accelerated simulations of materials.

KyuJung receives Ph.D. from UC Berkeley, Department of Materials Science and Engineering! Excited to move on to the next journey in the east coast.

KyuJung receives ECS Battery Division Graduate Student Award at Gothenburg, Sweden! I was honored to give an award presentation to the battery community, talking about how we can utilize high-throughput computing to discover Li superionic conductors, as well as how computational models can shed light on the correlation between rotational motion of polyhedra and lithium-ion hops.

KyuJung receives MRS Graduate Student Award, Silver medal at Boston!