Metal Chalcogenides for Pseudocapacitive Applications (Case No. 2016-178)

Summary

Researchers at UCLA have developed nanocrystalline, defect-rich metal dichalcogenide materials with expanded interlayer spacing that enable pseudocapacitive charge storage for Li⁺, Na⁺, Mg²⁺, and Ca²⁺ ion systems. These materials deliver high rate performance, suppress deleterious phase transformations, and enable fast charging/discharging while maintaining structural stability.

Background

Modern energy storage technologies require electrodes that can combine high energy density, fast kinetics, robust cycle life, and compatibility with various ion chemistries. Traditional layered dichalcogenides (e.g. MoS₂) often suffer from slow ion diffusion, phase changes under cycling, limited performance with multivalent ions, and poor rate capability. There's a significant need for materials that maintain pseudocapacitive behavior (fast surface or near-surface redox), avoid structural degradation, and deliver stable performance at high rates.

Innovation

This technology introduces metal chalcogenide nanoscale materials engineered with high density of defects and expanded interlayer spacing. The engineered structure allows for easier intercalation/deintercalation of ions without triggering major phase transitions that normally degrade performance. The innovations include optimizing synthesis to introduce stable defect structures, controlling layer spacing to balance ion access with material integrity, and demonstrating pseudocapacitive behavior (i.e. fast, reversible redox at or near surfaces) across multiple ion types. The system design yields devices (capacitor or battery style) with high power and good capacity retention.

Advantages

• High rate performance: supports fast charge/discharge cycles across multiple ions.

• Suppressed phase transitions: avoids degradation or hysteresis tied to structural changes.

• Good capacity and energy density for multiple ion types (Li, Na, Mg, Ca).

• Expanded interlayer spacing improves ion transport and accessibility.

• Robust structural stability, enabling longer cycle life and consistent performance.

• Compatible with composite electrode fabrication (with binders, conductive additives).

Potential Applications

• High-power supercapacitors or hybrid devices where fast energy delivery is required.

• Rechargeable battery systems with Li-ion, Na-ion, Mg-ion, or Ca-ion chemistries, especially in portable electronics or grid buffer roles.

• Applications where fast charging and high power are critical: EV fast-charging, backup power, load balancing.

• Wearable or flexible energy storage where durability, rate, and shape matter.

• Advanced energy storage in harsh environments or under high cycling demands.

Patent / Application

US 10,734,649 B2 — Metal Chalcogenides for Pseudocapacitive Applications
Metal Chalcogenides for Pseudocapacitive Applications (US10734649B2)

Publications by the Inventors

• John B. Cook, Hyung-Seok Kim, Terri C. Lin, Chun-Han Lai, Bruce Dunn, Sarah H. Tolbert, “Metal dichalcogenides for pseudocapacitive energy storage”, (Authors matching the patent), Advanced Energy Materials. DOI: 10.1002/aenm.201601283 — This paper reports the experimental validation of these pseudocapacitive metal chalcogenides, including data on cyclic voltammetry, rate capability, and structural stability in Li⁺/Na⁺/Mg²⁺/Ca²⁺ ion systems.