New 3D-Printed Electrode Improves Energy Storage
Next-generation electrochemical energy storage devices (EESDs) use ultrahigh active material loading (thicker electrodes) to increase energy density. However, thicker conventional electrodes increase the ion diffusion length and cause larger ion-concentration gradients, limiting reaction kinetics and EESD storage capacity. Livermore scientists, with collaborators at the University of California, Santa Cruz, have 3D printed a new compact device configuration to overcome these challenges. Their results are published in the July 25, 2024, issue of Nano-Micro Letters.
The new device has two interpenetrated, individually addressable electrodes, enabling precise control of the geometric features and interactions between them. The team used Livermore’s high-performance computing (HPC) capabilities to demonstrate through simulation that this electrode design improved the ion-diffusion kinetics in EESDs by shortening the ion-diffusion length and reducing ion-concentration inhomogeneity. In tests, the device enhanced volumetric energy density and capacity retention rate for a zinc–manganese dioxide battery system.
The new EESD architecture is applicable to lithium-ion and sodium-ion batteries, supercapacitors, and other storage systems and could benefit from enhancing the ion diffusion kinetics during the charging and discharging processes. “This new toolkit of materials and designs will enable high-performance energy storage in conditions relevant to national security missions and the broader energy storage community,” says Livermore’s Marcus Worsley, a co-lead author and group leader for Applied & Emerging Materials.
Contact: Marcus Worsley (925) 424-4831 (worsley2 [at] llnl.gov (worsley2[at]llnl[dot]gov)).
Demonstrating Grain-Boundary Phases in Alloys
Materials science faces a new frontier in grain boundary (GB) phase transitions. Grain boundaries are the interfaces between individual crystals in a material, and they heavily dictate the material’s strength, durability, and overall performance. GB phase transitions, or abrupt changes at a material’s interface, lead to distinct material structures and properties. Researchers from Lawrence Livermore, Ruhr-Universität Bochum, Stanford University, and the Max Planck Institute for Sustainable Materials have demonstrated for the first time how iron atoms undergo a GB transition when introduced to titanium. Their findings are published in the October 24, 2024, issue of Science.
To examine the effect of iron atoms on the structure of GBs in titanium, the team used atomic-resolution scanning transmission electron microscopy and correlated their observations with advanced computer simulations. They found that iron atoms segregate, or concentrate, to form unusual quasicrystalline-like structures at the interface—something never seen previously in alloys. This behavior, originating from the fivefold symmetry of icosahedral (having 20 faces, 12 vertices, and 30 edges) units formed during iron segregation, deviates from the classic picture of segregation and deepens understanding of interface complexity. Livermore physicist Timofey Frolov says, “This segregated alloy structure is nothing like we have seen before. The icosahedral units cluster together at the interface forming agglomerates of different sizes and shapes depending on the amount of iron.”
Contact: Timofey Frolov (925) 423-1469 (frolov2 [at] llnl.gov (frolov2[at]llnl[dot]gov)).
Livermore to Lead Lithography Research Effort
For decades, Lawrence Livermore has supported advanced laser, optics, and plasma physics research. This work has been critical to develop the underlying scientific principles the semiconductor industry uses to manufacture advanced microprocessors. Today, these computer chips drive innovations in areas from AI to HPC. Now, Livermore will lead a new research partnership to lay the groundwork for the next evolution of extreme ultraviolet (EUV) lithography, centered around a Laboratory-developed driver system called the Big Aperture Thulium (BAT) laser.
Along with scientists from SLAC National Accelerator Laboratory, Advanced Semiconductor Materials Lithography San Diego, and the Advanced Research Center for Nanolithography, the Livermore-led team will collaborate with other researchers through the Department of Energy’s Microelectrons Science Research Centers that aim to advance the basic science driving future microelectronic systems. The Livermore project is specifically focused on expanding the fundamental science around EUV generation and plasma-based particle sources. The team will test the BAT laser’s ability to increase EUV source efficiency by about 10 times compared to current industry standard carbon dioxide lasers. “This project will establish the first high-power, high-repetition-rate, target-shooting laser at Livermore,” says project co-principal investigator Jackson Williams. “The capabilities enabled by the BAT laser will have a significant impact on the fields of high-energy-density physics, inertial fusion energy, and industrial imaging.”
Contact: Jackson Williams (925) 423-8856 (williams270 [at] llnl.gov (williams270[at]llnl[dot]gov)).
