A thyristor will stay conducting until the current through the device is zero (“current zero”) or perhaps slightly negative.  LLNL’s approach is to use the opticondistor (“OTV”) to force this current zero in order to force the device into an “off” state.  By combining a light-activated thyristor with an OTV, a noise-immune, high efficiency, high-power switching device can be constructed. The…

LLNL researchers have invented an ultrafast PCSS to drive a high-power laser diode with arbitrary pulse widths.  These devices operate by supplying a high voltage (>10 kV) to one side of the switch.  A short pulse of light illuminates the semiconductor, instantly turning it from highly resistive to highly conductive.

The approach is to leverage the fact that a momentary “load” equal to the power transmission line impedance, (Z0), during the transient can suppress its propagation.  Z(0) is typically a fixed impedance of several hundred ohms based on the geometry of most single wire transmission lines.

So, an isolated self-powered opticondistor (OTV) system may provide an ultrafast method of…

LLNL’s novel approach is to use diamond substrates with the desired donor (nitrogen) and acceptor (boron) impurities.   In order to optically activate these deep impurities, the invention requires at least one externally or internally integrated light source.  The initial exposure to light can set up the desired conduction current, after which the light source could be turned off.  Even with…

Instead of producing individual DSRDs and bonding them, Tunnel DSRD's entire stack structure is grown epitaxially on a n- or p-type silicon wafer, resulting in a novel, “monolithic” stacked DSRD.  A tunnel diode is essentially a diode with very highly doped p and n regions such that the reverse breakdown voltage is 200 meV or lower. 

LLNL’s novel approach to enable MVDC power systems to operate safely is to develop a wideband gap bulk optical semiconductor switch (WBG BOSS) circuit breaker.  For higher power, efficiency and temperature operation, vanadium-doped silicon carbide (V-doped SiC) appears to be the most promising basis for WBG BOSS circuit breaker (other dopants like aluminum, boron and nitrogen may further…

LLNL researchers has developed an approach to mitigate HER on the ‘plating’ electrode, which uses a sub-device as a rebalancing cell to restore electrolyte properties, including pH, conductivity, and capacity across the main device of the flow battery.  This sub-device, which may need to be powered externally, has three major physical components: (1) a cathode electrode, (2) an anode electrode…

LLNL has developed a novel methodology for using commercially available automated sensors and actuators which can be deployed at scale in large appliances and plug-in EVs to provide as needed electric grid stabilization capabilities. The approach comprises of a population of voltage relays with a range of setpoints that would gradually reduce load as voltage falls. More severe voltage…

Improving the active material of the Zn anode is critical to improving the practicality of Zn-MnO2 battery technology. LLNL researchers have developed a new category of 3D structured Zn anode using a direct-ink writing (DIW) printing process to create innovative hierarchical architectures.  The DIW ink, which is a gel-based mixture composed of zinc metal powder and organic binders, is extruded…

To address many of the aforementioned challenges of manufacturing LIBs and SSBs, LLNL researchers have developed a number of inventions that offer proposed solutions for their components:

For cooling a high power device, the novel approach is to use a thermoelectric cooler (TEC)-based embedded substrate with proper selection of the TEC material as an active cooler.  The packaging configuration of TEC allows cooling the entire die without the use of a fluid.  The process is compatible with the thin film TEC material.  Standard semiconductor processes can be used to manufacture…

For this method, a Silicon on Insulator (SOI) wafer is used to tailor etch rates and thickness in initial steps of the process.  The simple three step process approach is comprised of grayscale lithography, deep reactive-ion etch (DRIE) and liftoff of the SOI wafer.  The liftoff process is used to dissolve the insulating layer, thus separating sections of the wafer as individual silicon…

The approach is to use Charge Balance Layers (CBLs) to create a superjunction device in wide bandgap materials.  These CBLs enable the device to effectively spread the electric field over 2- or 3-dimensions within a semiconductor voltage sustaining layer instead of 1-dimension, thereby increasing the maximum voltage a device is capable of withstanding.  The challenge of using CBLs is the…

Lawrence Livermore National Laboratory (LLNL) is offering the opportunity to collaborate in accelerating artificial intelligence (AI) for applied science, including research in key areas such as advanced material design, 3D printing, predictive biology, energy systems, “self-driving” lasers and fusion energy research.

Clinical images have a wealth of data that are currently untapped by physicians and machine learning (ML) methods alike. Most ML methods require more data than is available to sufficiently train them. In order to obtain all data contained in a clinical image, it is imperative to be able to utilize multimodal, or various types of, data such as tags or identifications, especially where spatial…

Some COVID-19 diagnoses are utilizing computed tomography (CT)-scans for triage. CT-scans produce immediate results with high sensitivity. The digital images produced by a CT-scan require physicians to identify objects within the image to determine the presence of disease. Object identification can be done using machine learning (ML) techniques such as deep learning (DL) to improve speed and…

MimicGAN represents a new generation of methods that can “self-correct” for unseen corruptions in the data out in the field. This is particularly useful for systems that need to be deployed autonomously without needing constant intervention such as Automated Driver Assistance Systems. MimicGAN achieves this by treating every test sample as “corrupt” by default. The goal is to determine (a) the…

LLNL has developed a new system, called the Segmentation Ensembles System, that provides a simple and general way to fuse high-level and low-level information and leads to a substantial increase in overall performance of digital image analysis. LLNL researchers have demonstrated the effectiveness of the approach on applications ranging from automatic threat detection for airport security, to…

The design calculations that have been performed in exploring the potentialities of LLNL's new approaches to flywheel energy storage have been built on existing and past LLNL flywheel programs, including a program aimed at flywheel systems for the bulk storage of electricity at utility scale. To achieve the requirements of such systems, as mentioned above, LLNL has developed some key new…