Research · Energy Materials Lab

Research areas

High energy density Li-ion cathodes

Linking redox chemistry, ion transport, and structural evolution to design cathodes with high capacity and durable cycling.

Our group studies Li-rich layered oxides, high-Ni layered cathodes, and disordered-rocksalt materials. We resolve how high-valent transition-metal and oxygen redox, cation migration, oxygen dimerization, and phase evolution control capacity, voltage hysteresis or decay, and long-term stability. By integrating atomistic computation, synthesis, electrochemistry, and multiscale characterization, we translate degradation mechanisms into practical design rules.

O2-type layered structure, reversible transition-metal migration mechanism, and microscopy images after the first charge and discharge

Selected publications

Voltage decay and redox asymmetry mitigation by reversible cation migration in lithium-rich layered oxide electrodesNature Materials · 2020 Oxygen Dimerization-driven Cation Migration Induces Voltage Hysteresis in Disordered Rocksalt CathodesJournal of the American Chemical Society · 2025

Computational materials design

Using first-principles calculations, high-throughput screening, and machine learning to explore chemical space systematically.

First-principles calculations reveal mechanisms at time and length scales that are difficult to access experimentally. We screen synthesis feasibility, phase stability, redox energetics, voltage, ion diffusion, defect chemistry, and interfacial reactions across broad compositional spaces. High-throughput workflows and machine learning expand this search, while targeted synthesis and characterization close the loop between prediction and experiment.

Examples of atomistic structural relaxation, theoretical voltage prediction, and energy-landscape mapping

Selected publications

A theoretical framework for oxygen redox chemistry for sustainable batteriesNature Sustainability · 2022 Using first-principles calculations for the advancement of materials for rechargeable batteriesAdvanced Functional Materials · 2017

Sodium-ion battery materials

Establishing chemistry-specific design rules for affordable sodium-ion electrodes with high energy and long cycle life.

The larger size and distinct chemistry of Na ions produce stacking preferences, phase transitions, and transport behavior that cannot be treated as a simple extension of lithium-ion materials. We map the chemical space of layered sodium transition-metal oxides, predict structure and redox activity, and validate promising compositions experimentally. The goal is to discover electrode materials that combine energy density, rate capability, and structural reversibility.

Chemical-space mapping and cationic-potential-based structure prediction for P2 and O3 sodium layered oxides

Selected publications

Coupling structural evolution and oxygen-redox electrochemistry in layered transition metal oxidesNature Materials · 2022

Solid-state ion conductors and interfaces

An emerging direction connecting superionic-conductor design with stable solid-solid interfaces.

Building on our work on defect chemistry in sulfide electrolytes and cation order-disorder in halide superionic conductors, we investigate how lattice topology, defects, and local structure govern ion transport. We are extending these principles toward electrochemical and chemo-mechanical stability at buried electrode-electrolyte interfaces for durable all-solid-state batteries.

Cation-ordering models, ionic conductivity, and structural motifs in a trigonal halide lithium-ion conductor

Selected publications

Design of a trigonal halide superionic conductor by regulating cation order-disorderScience · 2023 Native defects in Li₁₀GeP₂S₁₂ and their effect on lithium diffusionChemistry of Materials · 2018