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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 613 records · Page 34
All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

Viscosity of transient glass-forming melt and its relation to foaming during batch-to-glass conversion

Primary foam, which affects the heat transfer into the glass batch and the final glass quality, occurs when a sufficient quantity of transient glass-forming melt evolves with viscosity low enough to close the open porosity of the reacting glass batch. To better understand how the fraction of transient melt and its viscosity affect the primary foam temperature range, we determined, with x-ray diffraction, the fraction and composition of the transient glass-forming melt in a heated waste glass melter feed as a function of temperature. Then we prepared a set of transient melts that occurred within the foaming temperature interval and measured their viscosities with spindle and falling sphere viscometers. Further, the results agree with the Adam-Gibbs and VFT viscosity-composition models, even for transient melt compositions outside of the models compositional validity range. As silica and other refractory particles dissolved in the predominantly borate transient melt while temperature increased, viscosity increased from the initial value of ~500 Pa s at the onset of foaming (~650°C) to a maximum of ~770 Pa s when silica dissolution was almost complete (~700°C). As temperature increased further, transient melt viscosity decreased to ~220 Pa s (~850°C) when the primary foam collapsed.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Characteristics of the sub-micron ash aerosol generated during oxy-coal combustion at atmospheric and elevated pressures

This paper is concerned with the effect of pressure on the particle size distribution and the size-segregated composition of the sub-micron ash aerosol created during oxy-coal combustion under near practical self-sustaining combustion conditions. The problem is important because pressurized oxy-coal combustion has been proposed as one promising technology to minimize CO 2 emissions. Sub-micron ash plays a major role in ash deposition mechanisms, which, in turn, can control boiler performance. In this work, the same bituminous coal was burned at pressures of 1, 8 and 15 bar in O 2 /CO 2 environments. Here, tests employed a 100 kW (rated) oxy-fuel combustor (OFC) operated at atmospheric pressure (1 bar) and a 300 kW (rated) entrained-flow pressurized reactor (EFPR) at elevated pressures (8 and 15 bar). Although these tests were conducted under near practical combustion conditions, confounding effects of peak flame temperature variations were minimized for the 1 bar and 15 bar tests, allowing the role of elevated pressure to be isolated. For the EFPR tests, a specially designed sampling system was used to sample sub-micron ash aerosols from the pressurized combustor and is described in detail. Results showed that at the same peak temperature but higher pressure, the fractions of ash aerosol partitioned into the PM 0.6 and PM 1 size fractions were greatly diminished. Moreover, elevated pressures caused significant changes in the composition of the (size-segregated) sub-micron aerosol, especially in its alkali content, which increased significantly. Examination of fractions of each element that ended up in the sub-micron fume suggested that, at constant temperature, the effect of pressure on vaporization of semi-volatile metals was very different from that on the release into the gas phase of non-volatile metals and could not be explained by equilibrium.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Hierarchical porous silicon structures with extraordinary mechanical strength as high-performance lithium-ion battery anodes

Abstract Porous structured silicon has been regarded as a promising candidate to overcome pulverization of silicon-based anodes. However, poor mechanical strength of these porous particles has limited their volumetric energy density towards practical applications. Here we design and synthesize hierarchical carbon-nanotube@silicon@carbon microspheres with both high porosity and extraordinary mechanical strength (>200 MPa) and a low apparent particle expansion of ~40% upon full lithiation. The composite electrodes of carbon-nanotube@silicon@carbon-graphite with a practical loading (3 mAh cm −2 ) deliver ~750 mAh g −1 specific capacity, <20% initial swelling at 100% state-of-charge, and ~92% capacity retention over 500 cycles. Calendered electrodes achieve ~980 mAh cm −3 volumetric capacity density and <50% end-of-life swell after 120 cycles. Full cells with LiNi 1/3 Mn 1/3 Co 1/3 O 2 cathodes demonstrate >92% capacity retention over 500 cycles. This work is a leap in silicon anode development and provides insights into the design of electrode materials for other batteries.

25 ENERGY STORAGE↗
DOE OSTI2021

Compositional patterning in irradiated alloys: Effective potentials and effective interfacial energy

Compositional patterning (CP) in binary alloys during energetic particle irradiation is studied using a kinetic model that considers two competing kinetic processes, a thermally activated one promoting macroscopic phase separation (MPS) of the concentration field c(r,t) and a forced one resulting in finite-range random atomic mixing. The forced mixing is modeled by a Gaussian relocation distribution with a characteristic distance R. A series of approximate kinetic models are introduced by expanding the mixing function into a series of n terms, thus replacing the non-local evaluations of the concentration field c(r'-r,t) by local derivatives of c(r,t). This approach makes it possible to obtain exact effective potentials and build steady-state diagrams for each order-n model. Phase field (PF) simulations using these order-n models reveal that near the onset of patterning, phase evolution is accurately described using an order-3 model, which changes smoothly from an extended Cahn-Hilliard free energy in the MPS regime to a one-mode Swift-Hohenberg functional in the CP regime. Deeper into the patterning regime, higher-order models are required to achieve convergence, yielding square-like concentration profiles characteristic of a strong segregation regime. These higher-order effective free energies are analogous to multimodal Swift-Hohenberg functionals. Here, a new definition for the effective interfacial energy is proposed in the CP regime, since the interfacial area is no longer an excess quantity in that regime, precluding the use of the standard thermodynamic definition of interfacial energy.

36 MATERIALS SCIENCE↗
DOE OSTI2026

Stabilizing Cathode–Electrolyte Interphase of Nickel-Rich Single-Crystal Cathodes for Lithium-Ion Batteries

Nickel-rich single-crystal (SC) layered oxides are promising cathode candidates for next-generation lithium-ion batteries (LIBs) owing to their high energy density and structural robustness against intergranular cracking. However, their intrinsic surface reactivity with liquid electrolytes accelerates parasitic reactions at the cathode–electrolyte interphase (CEI), leading to transition-metal dissolution, gas generation, and impedance buildup. In this work, we synthesized SC-Li x Ni 0.9 Mn 0.05 Co 0.05 O 2 (NMC9055, 1 ≤ x ≤ 1.2) using a eutectic-assisted method and investigated interface stabilization strategies. A nickel-deficient Li x Ni 0.6 Mn 0.2 Co 0.2 O 2 (NMC622, 1 ≤ x ≤ 1.2) coating was applied via evaporation-based deposition to suppress CEI degradation pathways. Structural and compositional analyses confirmed uniform shell formation and preserved particle integrity. Half-cell electrochemical testing against lithium metal revealed ∼10% higher capacity retention and improved reversibility compared with pristine SC NMC9055, particularly under high-voltage operation. In conclusion, these results highlight the critical role of controlled surface chemistry in mitigating CEI instability in nickel-rich SC cathodes, offering a pathway toward enabling durable high-energy LIBs.

Coating processes↗
DOE OSTI2026

Multiplicity dependence of f 0 (980) production in pp collisions at $\mathbf{\sqrt{s}}$ = 13 TeV

The dependence of f 0 (980) production on the final-state charged-particle multiplicity is reported for proton–proton (pp) collisions at the centre-of-mass energy, $\mathbf{\sqrt{s}}$ = 13 TeV. The production of (980) is measured with the ALICE detector via the decay channel in a midrapidity region of |y| < 0.5. The evolution of the integrated yields and mean transverse momentum of f 0 (980) as a function of charged-particle multiplicity measured in pp at $\mathbf{\sqrt{s}}$ = 13 TeV follows the trends observed in pp at $\mathbf{\sqrt{s}}$ = 5.02 TeV and in proton–lead (p–Pb) collisions at$\mathbf{\sqrt{s_{NN}}}$ = 5.02 TeV. Particle yield ratios of f 0 (980) to π ± and K* (892) are found to decrease with increasing charged-particle multiplicity. These particle ratios are compared with calculations from the canonical statistical thermal model as a function of charged-particle multiplicity. The thermal model calculations provide a better description of the decreasing trend of particle ratios when no strange or antistrange quark composition for f 0 (980) is assumed, which suggests that the data do not support significant hidden strangeness in the f 0 (980).

Abualrob, I. J. [University of Houston] (ORCID:000↗
DOE OSTI2021

Effect of Composition on the Phase Structure and Magnetic Properties of Ball-Milled LaFe11.71-xMnxSi1.29H1.6 Magnetocaloric Powders

Magnetocaloric alloys are an important class of materials that enable non-vapor compression cycles. One promising candidate for magnetocaloric systems is LaFeMnSi, thanks to a combination of factors including low-cost constituents and a useful curie temperature, although control of the constituents’ phase distribution can be challenging. In this paper, the effects of composition and high energy ball milling on the particle morphology and phase stability of LaFe11.71-xMnxSi1.29H1.6 magnetocaloric powders were investigated. The powders were characterized with optical microscopy, dynamic light scattering, X-ray diffraction (XRD), and differential scanning calorimetry (DSC). It was found that the powders retained most of their original magnetocaloric phase during milling, although milling reduced the degree of crystallinity in the powder. Furthermore, some oxide phases (<1 weight percent) were present in the as-received and milled powders, which indicates that no significant contamination of the powders occurred during milling. Finally, the results indicated that the Curie temperature drops as Fe content decreases (Mn content increases). In all of the powders, milling led to an increase in the Curie temperature of ~3–6 °C.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2021

BETO 2021 Peer Review - FCIC Task 6: High Temperature Conversion

The impacts of feedstock variability on pyrolysis processes are significant but poorly defined. Current engineering designs are based on empirical guidelines, useful only over a narrow range of feedstock properties. The objectives of this project are to (1) Develop science-based knowledge of how feedstock attributes and operational parameters impact pyrolysis process reliability and product quality; and (2) Build an experimental and computational toolset that predicts these outcomes, enabling processes to optimize reliability and product quality. Biomass is a complex feedstock. Controlling for and testing the effects of individual attributes is very challenging. This project couples multiscale experimentation and modeling to accurately capture the fundamental physics and chemistry of biomass flow and conversion behavior in feeding and pyrolysis reactor operations. Our focus is on pine residue attributes – anatomical fraction (bark, needles, wood), particle morphology (size/shape distribution, density, porosity), and chemical composition (extractives, biopolymers, alkali metals) – that impact product quality for downstream catalytic upgrading. Because detailed pyrolysis product characterization is limited, cutting-edge analytical techniques are being developed to reveal impactful product attributes. The tools and knowledge developed here will enable integrated pyrolysis-based processes that are more robust, flexible, and market-responsive with respect to feedstock variability.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2025

An open-source hybrid unstructured mesh - CAD fusion multiphysics analysis workflow in SALAMANDER

Plasma facing components in fusion devices will endure extreme neutron and heat fluxes. To facilitate their design using simulation tools, the open-source Fusion Module, Fusion ENergy Integrated multiphys-X (FENIX) framework is being developed to model these components with a high-fidelity multi-physics multi-dimensional approach. It can iteratively resolve couplings between all the physics at play, from neutron radiation, to thermomechanics, to near-wall plasma dynamics. This framework is based on the Multiphysics Object Oriented Simulation Environment (MOOSE), which is developed by a collaboration of US National Laboratories since 2008, for advanced nuclear, geomechanics simulations and other applications. FENIX couples numerous simulation tools, including OpenMC, the Tritium Migration Analysis Program v8, the NekRS CFD software, and most MOOSE modules. For the coupling of radiation transport and other physics, FENIX supports a hybrid workflow between Computer Assisted Design (CAD) and unstructured mesh geometries. The CAD can be generated from skinning the unstructured mesh, to enable a coarse geometry for efficient particle transport, but still resolving the local material compositions and temperature gradients. Neutron transport is performed using DAGMC on the CAD, and Cardinal, integrated in FENIX, maps tallied quantities, such as the heat deposition or the tritium generation rates, from a tally volumetric mesh to the other physics’ unstructured mesh. This coupling was exercised on a simplified tokamak geometry, coupling neutron transport with the heat conduction equation, and on a monoblock divertor problem, coupling additionally with tritium migration. Mesh convergence studies highlight the importance of the mapping conservativeness. Coupling with thermo-mechanics is further enabled by the generalization of the approach to moving meshes. The presentation will include these coupled analysis as well as an update on status of the FENIX framework.

70 - PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2024

Simulant Development of Potential 200 West Area Waste Feeds

Preliminary planning for retrieval, qualification, and pretreatment of waste in Hanford’s 200 West Area (200W) has begun as part of the West Area Risk Management project. Experimental studies to technically mature pretreatment process operations will likely be needed because of the uniqueness of 200W waste. Pacific Northwest National Laboratory formulated five simulants to represent 200W-qualified feed based on the preliminary flowsheet provided by Washington River Protection Solutions, LLC. The simulant recipes were devised using applicable historical information as a reference point to support the use of the flowsheet waste vectors, which were combined into five distinct groups. These five groups formed the basis for the liquid composition targets that were adapted into recipes using charged-balanced salt species. The liquid phase recipes were batched in 1-L quantities and analyzed at Pacific Northwest National Laboratory. Once confirmed to be stable, the liquid solutions were tested for compatibility with candidate solid components. Specific solid components were recommended based on cross-examining the proposed solid phases in the flowsheet with relevant data from the literature. Mixtures of solid components were added to aliquots of the liquid batches and sub-sampled to measure particle size distribution. The measured distribution was compared to independently created benchmark distributions appropriate for each simulant. This process was iterated until a solid phase composition that resulted in a representative particle size distribution was found. After the final compositions were confirmed, a suite of chemical and physical characterization data was collected. This report describes the simulant basis, formulation methodology, laboratory measurements, and data collected for the recipes recommended to represent 200W waste feeds.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2023

Quality Control Methods for Measurement of UCO Kernel Composition and SiC Microstructure

Quality control (QC) is critically important to tristructural-isotropic (TRISO) particle fuels owing to the complexity of and reliance on the fuel form to contain fission products during irradiation. Characterization methods for particle fuel QC have decades of history and have continued to develop as new insights into fuel performance inform revised fuel specifications and as advances in underlying technologies expand the possibilities of what may be characterized. Two relatively new methods for characterization of TRISO fuels have been published in open literature: optical microscopy image analysis for mixed uranium carbide/uranium oxide (UCO) kernel composition analysis and automated grain boundary detection in backscattered electron (BSE) images of the silicon carbide (SiC) layer in TRISO particles for grain size characterization. Suggestions and guidelines for the application of these methods to TRISO fuel qualification are provided in this report.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2022

Atmospheric particle abundance and sea salt aerosol observations in the springtime Arctic: a focus on blowing snow and leads

Abstract. Sea salt aerosols play an important role in the radiation budget and atmospheric composition over the Arctic, where the climate is rapidly changing. Previous observational studies have shown that Arctic sea ice leads are an important source of sea salt aerosols, and modeling efforts have also proposed blowing snow sublimation as a source. In this study, size-resolved atmospheric particle number concentrations and chemical composition were measured at the Arctic coastal tundra site of Utqiaġvik, Alaska, during spring (3 April–7 May 2016). Blowing snow conditions were observed during 25 % of the 5-week study period and were overpredicted by a commonly used blowing snow parameterization based solely on wind speed and temperature. Throughout the study, open leads were present locally. During periods when blowing snow was observed, significant increases in the number concentrations of 0.01–0.06 µm particles (factor of 6, on average) and 0.06–0.3 µm particles (67 %, on average) and a significant decrease (82 %, on average) in 1–4 µm particles were observed compared to low wind speed periods. These size distribution changes were likely caused by the generation of ultrafine particles from leads and/or blowing snow, with scavenging of supermicron particles by blowing snow. At elevated wind speeds, both submicron and supermicron sodium and chloride mass concentrations were enhanced, consistent with wind-dependent local sea salt aerosol production. At moderate wind speeds below the threshold for blowing snow as well as during observed blowing snow, individual sea spray aerosol particles were measured. These individual salt particles were enriched in calcium relative to sodium in seawater due to the binding of this divalent cation with organic matter in the sea surface microlayer and subsequent enrichment during seawater bubble bursting. The chemical composition of the surface snowpack also showed contributions from sea spray aerosol deposition. Overall, these results show the contribution of sea spray aerosol production from leads on both aerosols and the surface snowpack. Therefore, if blowing snow sublimation contributed to the observed sea salt aerosol, the snow being sublimated would have been impacted by sea spray aerosol deposition rather than upward brine migration through the snowpack. Sea spray aerosol production from leads is expected to increase, with thinning and fracturing of sea ice in the rapidly warming Arctic.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2025

Development and characterization of an aerosol-generated multi-method analytical particle test material

Ceria (CeO 2 ) particles with low to ultra-low loading of nickel dopant were produced using an aerosol-based, droplet-to-particle synthesis via an in-line calcination technique. This aerosol-based synthesis method enables the production of particles with a monodisperse size distribution. These produced and well-characterized, multi-element, ceria-based particles demonstrate a material exemplar for multi-method analytical testing. They were prepared from a cerium nitrate feedstock where low loading nickel dopant was added at target Ni/(Ni + Ce) atomic percents of 1 %, 0.1 %, and 0.01 %, using a nickel nitrate spike. This methodology proved to produce ceria particles doped with a dynamic range of low to ultra-low loadings of nickel over a 24-h period, with consistent size distribution, morphology, and composition. The successful incorporation of nickel was demonstrated with bulk and single particle inductively coupled plasma mass spectroscopy and revealed notable particle-to-particle elemental homogeneity. X-ray photoelectron spectroscopy demonstrated the presence of a high concentration of nickel dopant incorporated preferentially toward the surface of the particles, and that this dopant aided oxidation of surface Ce(III) atoms to Ce(IV). These particle test materials were then validated through X-ray absorption near edge spectroscopy, comparing the ultra-low 0.01 % Ni and low 1 % Ni-doped ceria samples. This revealed a more-reduced oxidation state of the nickel with an increase in dopant concentration. Finally, this work demonstrates a synthesis and systematic characterization scheme to produce multi-method analytical test particulates.

36 MATERIALS SCIENCE↗
DOE OSTI2024

Gamma-ray imaging of Np-237 metal using an organic glass imager

Neutron and gamma-ray imaging systems are deployed within the field of nuclear safeguards for the detection and localization of special nuclear materials and other materials of interest. 237 Np is one of these materials of interest due its presence in spent nuclear fuel and potential for use in nuclear weapons when purified. Here, for the first time, a 6 kg neptunium sphere (98.8 wt% 237 Np) was measured using a dual-particle imager, from the University of Michigan, consisting of organic glass and inorganic scintillators. The novel composition of organic glass scintillator was recently developed at Sandia National Labs and has been used in particle imaging systems due to its time resolution and particle discrimination capabilities. Gamma-ray energy spectra from single and coincident events were extracted and the sequencing of Compton scatter and photoelectric absorption gamma-ray events was used to generate images using simple backprojection. The emissions of interest in this work are the 312 keV and 416 keV gamma rays from 233 Pa, a daughter isotope from the neptunium decay series. The results of this work show that there is close agreement between the true source location in angular space and the converged location from the gamma ray images created using the system. The gamma spectroscopy from single and coincident events also identified the characteristic emission from the daughter isotope and could be used to assist with the identification of 237 Np. Furthermore, successful localization of the source with 5 s of data demonstrates the practical application of the imaging system for imaging and detection of material in weapons-useable quantities.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2021

Rapid consolidation method for preparing bulk metastable iron-rich materials

Interstitially modified compounds of rare earth element-containing, iron-rich compounds may be synthesized with a ThMn 12 tetragonal crystal structure such that the compounds have useful permanent magnet properties. It is difficult to consolidate particles of the compounds into a bulk shape without altering the composition and magnetic properties of the metastable material. A combination of thermal analysis and crystal structure analysis of each compound may be used to establish heating and consolidation parameters for sintering of the particles into useful magnet shapes.

Zhou, Chen↗
DOE OSTI2025

Compositing and Characterization of SE Quadrant Waste Exemplars

This report outlines the experimental investigation and characterization of transport properties in Hanford SE quadrant High-Level Waste (HLW). The goal of the study was to establish baseline behaviors of bulk composite rheology and settling characteristics to facilitate waste treatment process design for the Waste Treatment and Immobilization Plant (WTP) and avoid waste conditions and properties favorable to bubble cascade gas release events. The study focused on two major objectives: 1) identifying, obtaining, and preparing relevant Hanford tank waste samples for evaluation and 2) quantifying the “as-received” rheology and transport properties of the samples. Twenty-three centrifuged core segments originating from tanks AN-101, AN-106, and AW-105 were selected based on compositional relevance to SE quadrant PUREX cladding waste. These materials were composited into five waste composites enriched with target analytes: aluminum (Al), iron (Fe), phosphate (PO 4 ), uranium (U), and zirconium (Zr). Physical property and transport testing examined particle size distributions, bulk densities, settling behaviors, rheological properties, shear strengths, and just-suspended mixing speeds (NJS). Testing revealed two distinct composite classifications based on rheological characteristics: non-Newtonian composites (Fe and PO 4 ) and Newtonian composites (Al, U, and Zr). The Fe and PO 4 composites exhibited slow settling rates and reduced mobilization proclivity, attributable to strong particle-particle interactions and the formation of yield structures within non-Newtonian slurries. In contrast, the Al, U, and Zr composites displayed rapid settling and dense compaction behaviors, indicative of minimal structuring and interactions. Shear strengths for all composites were generally low relative to prior studies of SE quadrant waste, with only the U composite showing elevated strength approaching values reported in previous literature. Repeat shear strength measurements revealed contributions from dense granular material in the U composite and stronger cohesive properties in the Al composite. Settling data highlighted hindered settling behavior, with rates falling more than one order of magnitude below estimates based on Stokes’ law and rate decreasing as composite UDS content increased. NJS testing demonstrated different mobilization behaviors between cohesive and granular composites. The Fe composite required the highest mixing rate for resuspension, while the Al composite was the easiest to resuspend. Comparison of measured NJS against predictions made using the Zwietering correlation suggests non-Newtonian behavior alters resuspension mechanics, rendering non-Newtonian systems more stable against resuspension lift forces relative to their granular counterparts.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2025

Challenges and Opportunities in State‐of‐the‐Art Proteomics Analysis for Biomarker Development From Plasma Extracellular Vesicles

Extracellular vesicles (EVs) are membrane-bound particles secreted by cells, playing crucial roles in intercellular communication. The composition of EVs can undergo changes in response to stress and disease conditions, making them excellent biomarker candidates. However, extracting protein information from EVs can be challenging due to their low abundance in complex biofluids and copurification with contaminant proteins and particles. Techniques to enrich EVs have their strengths and limitations, without one being able to purify EVs to complete homogeneity. This can lead to compromised recovery rates and increased complexity, making data interpretation difficult. In this viewpoint article, we explore the concept that better characterization of EV composition, followed by quantification of EV proteins in complex samples, might be a more viable route for biomarker development. Mass spectrometers can provide reproducible deep coverage of the EV proteome, despite sample impurities. This paradigm shift presents opportunities to integrate advanced bioinformatics tools to refine the EV proteome landscape, identify novel biomarkers, and streamline validation processes in biomarker development. By focusing on leveraging technology rather than achieving absolute purity, this approach can transform current practices and open opportunities for robust biomarker discovery. Herein, we highlight not only such opportunities but also challenges to implement this concept.

Dakup, Panshak P. [Pacific Northwest National Labo↗
DOE OSTI2023

A04-0491 - Reduced Electrolyte Reactivity of Pitch-Carbon Coated Si Nanoparticles for Li-Ion Battery Anodes

Silicon-based anodes for Li-ion batteries (LIB) have the potential to increase the energy density over graphite-based LIB anodes. However, silicon anodes exhibit poor cycle and calendar lifetimes due to mechanical instabilities and high chemical reactivity with the carbonate-based electrolytes that are typically used in LIBs. In this work, we synthesize a pitch-carbon coated silicon nanoparticle composite active material for LIB anodes that exhibits reduced chemical reactivity with the carbonate electrolyte compared to an uncoated silicon anode. Silicon primary particle sizes <10 nm minimize micro-scale mechanical degradation of the anode composite, while conformal coatings of pitch-carbon minimized the parasitic reactions between the silicon and the electrolyte. When matched with a high voltage NMC622 cathode, the pitch-carbon coated Si anode retains -75% of its initial capacity over 1000 cycles. Efforts to increase the areal loading of the pitch-carbon coated silicon anodes to realize real energy density improvements over graphite anodes results in severe mechanical degradation on the electrode level. Developing procedures to engineer the architecture of the composite silicon anode may be a solution to this mechanical challenge.

DIRECT ENERGY CONVERSION,ENERGY STORAGE↗