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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 37 records · Page 2
All sourcesNASA NTRSDOE OSTI
DOE OSTI2025

Metallicity, Atomic Disorder, and Li-Ion Storage in Fast-Charging Anodes

Oxides of Nb with Wadsley-Roth shear structures comprise a family of stable, high-rate anode materials for Li-ion batteries. A particular pair of them offers the unusual opportunity to test how important metallic conduction of the starting electrode is for electrode performance. The selected pair of compounds with similar 4 × 3 Wadsley-Roth block structures are insulating Ti 2 Nb 10 O 29 and metallic Nb 12 O 29 . A combination of diffraction, electrochemistry, magnetic measurements, and entropic potential measurements is employed to establish key findings for these two anode materials. We find that starting with a metallic oxide is not especially advantageous over a comparable material that readily transitions into a metallic state upon lithiation. Second, the rate performance appears to be dictated by ion mobility, and atomic Ti/Nb disorder in Ti 2 Nb 10 O 29 contributes to improved capacity retention at high rates by suppressing Li-ion ordering. However, subtle details in the nature of redox processes make Nb 12 O 29 a slightly better electrode material for long-term cycling at slower rates.

crystal structure↗
DOE OSTI2026

Interface-engineered (CrMnTiZnCo) 3 O 4 @polypyrrole nano-hybrids for superior lithium storage

High-entropy oxides (HEO) have emerged as promising anode materials for lithium-ion batteries (LIBs) due to their high theoretical specific capacity. However, their practical application is hindered by several challenges, including significant volume expansion, electrode pulverization, and substantial irreversible capacity loss during initial cycles. To address these limitations, this study designed a novel core-shell composite material, denoted as HEO@PPy, which consists of a (CrMnTiZnCo) 3 O 4 -based HEO core and a polypyrrole (PPy) shell. This composite demonstrates remarkable electrochemical performance: it maintains a specific capacity of 1090.1 mAh/g after 100 cycles at 100 mA/g and retains 521.8 mAh/g after 1000 cycles at 1 A/g, highlighting its superior cycling stability. Furthermore, it exhibits excellent rate capability, delivering a capacity of 372.1 mAh/g even at a high current density of 5 A/g. These findings confirm that the strategic compositional and structural design of HEOs, combined with hybridization with conductive polymers like PPy, provides a viable pathway for developing advanced anode materials for next-generation, high-performance lithium-ion batteries.

25 ENERGY STORAGE↗
DOE OSTI2024

Zero-strain high entropy spinel oxide (FeNiCuCrMn) 3 O 4 @rGO as high-performance anode for sodium ion battery

High entropy spinel oxides (HEOs), as a new type of anode material with at least five transition metal elements and high theoretical specific capacity, have enormous promise in sodium ion batteries (SIBs). However, the influence of different transition metal elements on the structure and electrochemical performances of HEOs is not clear. Here, in this study, the addition of Mn to HEO can increase the surface oxygen vacancy (O v ) concentration, shorten the band gap, and enhance the electrochemical performance of (FeNiCuCrMn) 3 O 4 @rGO. XPS results show (FeNiCuCrMn)3O4@rGO has the highest surface O v concentration. Ab initio calculations demonstrate that the indirect band gap of (FeNiCuCrMn)3O4@rGO is 0.068 eV. In situ X-ray diffraction and synchrotron X-ray absorption spectroscopy reveal that (FeNiCuCrMn) 3 O 4 @rGO exhibits a zero-strain characteristic with an inconsequential unit cell volume change of 0.2 %. Specifically, (FeNiCuCrMn) 3 O 4 @rGO as anode materials for SIBs show good cyclic stability (with a capacity retention of 84 % at 500 mA g −1 after 3000 cycles). Overall, this work provides a new direction for optimizing transition metal elements in HEOs.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Synthesis and Lithium Storage Properties of Spinel (Al 0.2 Mn 0.2 Co 0.2 Ni 0.2 Zn 0.2 ) 3 O 4 High-Entropy Oxide

High-entropy oxides (HEOs) have garnered significant interest as next-generation anode materials for lithium-ion batteries (LIBs) due to their high theoretical specific capacity and excellent structural stability. This study successfully synthesized spinel-structured (Al 0.2 Mn 0.2 Co 0.2 Ni 0.2 Zn 0.2 ) 3 O 4 HEO via a sol–gel method. The material was characterized by XRD, Raman and TEM, confirming a homogeneous single-phase spinel structure, with uniformly distributed elements-a hallmark of HEOs. Electrochemical tests demonstrated a stable cycling performance (438 mAh g −1 at 100 mA g −1 after 100 cycles and 350 mAh g −1 at 1 A g −1 after 1000 cycles) and rate capacity of 159 mAh g −1 at 2 A g −1 , The remarkable long-term cyclability and good rate capability highlight the potential of this HEO for practical applications in durable, high-power lithium-ion batteries. This work underscores the advantage of incorporating structurally stabilizing elements in HEOs for advanced energy storage.

anode materials↗
DOE OSTI2026

Techno-Economic Analysis of Recycling Strategies for Catalyst and Acid During Catalytic Graphitization

With the aim of meeting the urgent demand for active anode materials (AAM) in energy storage systems, bio-based graphite (biographite) emerges as an affordable solution to de-risk the turbulent supply chain of critical minerals. Anode grade biographite requires high crystallinity and purity, which can be achieved by catalytic graphitization with iron, followed by acid washing. Therefore, a well-conceived process integration that recycles catalyst can be the starting point to commercialization. This study evaluates closed-loop catalyst recovery, and byproducts valorization scenarios through a technoeconomic framework to help understand the scale-up potential of biographite. For the acid washing, three reactors in series meet the required biographite purity at 99.95%. Iron and acid recovery can reduce material consumption and waste generation by ~95%, albeit at the expense of ~80% increase in capital costs. Recovery scenarios present similar capital and operational expenses, yielding minimum selling prices (MSP) near $6 kg-1 of biographite. Monte Carlo methodology reveals that feedstock price accounts for ~60% of MSP variance, followed by plant capacity ~20%. The likelihood of reaching a competitive profit margin of 30% in the U.S. AAM market sits at 85% average for recovery scenarios, and 103% when iron oxide is sold as byproduct. Additionally, an IRR >= 15% can be achieved for half of Monte Carlo simulations, representing promising early-stage results. Biographite production offers a strategic pathway to stabilize the anode market beyond China by integrating established technologies for a scalable, economically viable, and sustainable process. The role of catalyst recovery and byproducts utilization is critical for advancing the biomaterials industry.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2025

Energy, greenhouse gas, and water life cycle analysis of synthetic graphite anode production in the United States

This study presents a comprehensive life cycle analysis of potential synthetic graphite battery anode material (BAM) production in the U.S. based on industrial-scale data. The analysis focuses on three impacts: greenhouse gas (GHG) emissions, total energy use, and water consumption. We also conducted sensitivity analyses to evaluate the effect of variation in process parameters and energy sources used for synthetic graphite BAM production on its life cycle GHG emissions. A detailed supply chain analysis of graphite BAM in the U.S. was also undertaken, along with a study of its associated GHG emissions. The results show GHG emissions of 29.7 kg CO 2 -eq. per kg BAM, total energy use of 580 MJ kg −1 BAM, and water consumption of 121 L kg −1 BAM for the baseline condition. The graphitization step is a major process hotspot, contributing to over 74% of all impacts. This is attributed to the energy and material input requirements for this step, particularly through the use of crucibles. Across the entire synthetic graphite production process, electricity is the primary contributor, followed by crucibles used in graphite block production, and then calcined petroleum coke. Sensitivity analyses indicate that improvement in micronization yield, reuse of crucibles, and use of low-carbon nuclear energy can significantly reduce GHG emissions of potential domestic graphite production (by ∼70%). Supply chain analysis identified major graphite BAM sources in the U.S. and showed that the U.S. has a competitive advantage in domestic production of synthetic graphite BAM in terms of reduced life cycle GHG emissions compared to present-day imported sources (by ∼20%).

Battery anode↗
DOE OSTI2025

Transforming CO 2 to Porous Carbon as a High-Performing Sodium-Ion Battery Anode via Electrochemical Reduction in Molten Carbonates

The prevalence of sodium over lithium prompts exploration of sodium-ion batteries (SIBs) as a viable alternative to lithium-ion batteries (LIBs). Hard carbon has emerged as a promising anode material for SIBs, yet its synthesis poses sustainability challenges and emits pollutants. Here, in this study, we introduce CO 2 -derived porous carbon (graphitic and amorphous) as an anode for SIBs via electrochemical reduction of CO 2 in a molten eutectic carbonate salt at a lower temperature that yields materials with controlled microstructure, morphology, and porosity conducive to energy storage. Our CO 2 -derived carbon demonstrates remarkable specific capacity, superior rate capability, and stable cycling performance as a SIB anode. This innovative strategy harnesses waste CO 2 toward advancing SIB energy technology.

CO2-derived carbon↗
DOE OSTI2025

Enhanced Performance of Silicon Anodes through Hybrid Surface Engineering

Silicon (Si) is a promising anode material for nextgeneration lithium-ion batteries (LIBs) due to its high theoretical capacity. However, Si-containing anodes typically suffer from unacceptably short lives because of the unrestricted growth of the solid electrolyte interphase (SEI). Here, in this study, hybrid surface coatings are developed to stabilize the SEI in high loading pure Si anodes using atomic and molecular layer deposition. The coatings, consisting of LiF paired with lithicone, create an ionically conductive surface that enhances the capacity retention, rate performance, and longevity. Careful binder selection helps demonstrate the full utility of the coatings by enabling high loading electrodes to cycle continuously at current densities of 1200 mA/g Si . Uncoated controls, in comparison, fail within just 10 cycles at lower loadings. X-ray photoelectron spectroscopy and electrochemical impedance spectroscopy are used to provide supporting evidence of the coating composition and efficacy. The data indicate that our lithicone coating is converted to Li 2 CO 3 upon cycling contributing to favorable LiF/Li 2 CO 3 interfaces that enhance the space-charge effect at the active material’s surface. When applied to electrodes made with thermally stable binders and increasingly higher loadings (approaching 5 mAh/cm 2 ), ion transport through the bulk electrode, rather than SEI growth, is shown to be the limiting factor. Furthermore, data suggests a favorable interaction between lithicone precursors and poly(acrylic acid) binders mitigates thermal decomposition at higher temperatures. The work presented here represents the successful realization of composite coatings containing LiF/Li 2 CO 3 components to stabilize high-loading Si anodes. This work helps inform advanced surface engineering strategies to achieve highly reversible, high-capacity Si anodes capable of fast charging for high-performance LIBs.

atomic layer deposition↗
DOE OSTI2025

Scale-Up of Novel Li-Conducting Halide Solid State Battery Electrolyte

LBNL and project partner Saint Gobain (SG) demonstrated scalable processing of halide-based solid state batteries. SG’s innovative halide-based SSE utilized in this project is inherently scalable: it can be compressed into a dense electrolyte sheet at room temperature under moderate pressure, can be processed in dry air, and does not present any safety issues during processing or end use. The halide material forms the dense electrolyte layer, and is dispersed in the thick cathode to form a highly conductive path for Li ions. The halide also comes in contact with various environments and other materials (solvents, binders, processing equipment, etc.) throughout the battery manufacturing process, and must be stable in contact with cathode and anode materials during operation.

25 ENERGY STORAGE↗
NASA NTRS1979

Electrochemistry of lunar rocks

Electrolysis of silicate melts has been shown to be an effective means of producing metals from common silicate materials. No fluxing agents need be added to the melts. From solution in melts of diopside (CaMgSi2O6) composition, the elements Si, Ti, Ni, and Fe have been reduced to their metallic states. Platinum is a satisfactory anode material, but other cathode materials are needed. Electrolysis of compositional analogs of lunar rocks initially produces iron metal at the cathode and oxygen gas at the anode. Utilizing mainly heat and electricity which are readily available from sunlight, direct electrolysis is capable of producing useful metals from common feedstocks without the need for expendable chemicals. This simple process and the products obtained from it deserve further study for use in materials processing in space.

Lindstrom, D. J.↗
DOE OSTI2025

Comparative Study of Vinylene Carbonate and Lithium Difluoro(oxalate)borate Additives in a SiO x /Graphite Anode Lithium-Ion Battery in the Presence of Fluoroethylene Carbonate

The SiO x /graphite composite is recognized as a promising anode material for lithium-ion batteries (LIBs), owing to the high theoretical capacity of SiO x combined with the excellent stability of graphite. However, the inherent disadvantage of volume expansion in silicon-based anodes places significant challenges on the solid electrolyte interphase (SEI) and severely degrades the electrochemical performance. Rational formulation of electrolyte, including its additives, is crucial in accommodating and optimizing the composition of the SEI and enhancing the cell performance. In this work, we present a comparative study of vinylene carbonate (VC) and lithium difluoro(oxalate)borate (LiDFOB) additives combined with fluoroethylene carbonate (FEC) in the electrolyte for SiO x /graphite∥LiNi 1–x–y–z Co x Mn y Al z O 2 full cells. VC outperformed LiDFOB as an additive, delivering higher capacity cycling, higher Coulombic efficiency, and better cycle stability up to 400 cycles. XPS and impedance analyses reveal that LiDFOB contributed to SEI/CEI with both a lower proportion of LiF and a higher proportion of poly(VC), which tended to produce higher cell impedance. XRD and XANES further indicated that using the LiDFOB additive, the NCMA cycled to a shallower degree than that of the VC additive. Although the VC additive maintained a higher capacity up to 400 cycles, microstrain and SEM analyses show a higher strained NCMA along with clear evidence of cracking over the surface of the NCMA particle in VC-based electrolyte but not in LiDFOB. In conclusion, this suggests that the negative influence of LiDFOB at the anode (inferior SEI) supersedes the negative impact of both a cracked NCMA and a deeper cycled NCMA and SiO x -based anode.

36 MATERIALS SCIENCE↗
DOE OSTI2026

Precious metal oxygen-evolving anodes for electrolytic reduction of metal oxides in molten LiCl-Li 2 O electrolyte

Understanding the electrochemical stability of oxygen-evolving anode materials in molten salt electrolytes is essential to enable decarbonized electrolytic reduction of metal oxides (e.g., used nuclear oxide fuels). Here, this work investigated three precious metals (Ir, Ru, and Pt) as oxygen-evolving anodes in molten LiCl-Li 2 O (99.0-1.0 wt%) at 650 °C. For consistent measurements, this work employed a three-electrode cell comprised of a two-phase Li-Bi (65-35 at%) reference electrode and a NiO counter electrode. Anodic polarization behavior of each anode was investigated via cyclic voltammetry (CV) and chronoamperometry. The onset potential for oxygen evolution was observed at E > 2.9 V (vs. Li/Li + ) for the Ir and Ru anodes and anodic current density was as high as 1.0 A cm -2 at 3.23 V. The dimensional stability of each anode was evaluated from long-term electrolysis experiments (10.0-32.1 h) at 3.23 V. Rapid consumption of the Pt anode was observed after the application of 26,453 C cm -2 with a reduction in diameter of about 15.8% due to the formation of a non-protective Li 2 PtO 3 compound. The formation of this compound was also observed during CV measurements as additional anodic waves at potentials more negative than that of oxygen evolution. In contrast, both the Ir and Ru anodes exhibited excellent dimensional stability with a reduction in diameter or thickness of less than 1.5% even after applying greater charge density of ~41,100 C cm -2 , demonstrating superior stability during oxygen evolution in the LiCl-Li 2 O electrolyte.

11 - NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2024

CRADA Final Report: Ultralong Cycle Life and Ultrafast Charging Batteries to Electrify High Duty-Cycle, Mobile Platforms

As part of the Cyclotron Road program, Tyfast Energy Corp. aimed to investigate the Li 3 V 2 O 5 (LVO) anode material for next generation lithium batteries. State of the art and fast charging lithium-ion batteries are based on the lithium titanate or Li 4 Ti 5 O 12 (LTO) anode chemistry. LTO cells demonstrate fast charging times (<6 mins), long cycle life (>20,000 cycles), but at the expense of very low energy density (<200Wh/L, <80Wh/kg). Silicon anodes have the promise of achieving fast charging times, however, issues with cycling stability in combination with fast charging is unknown. LVO has unique properties that enable new performance window for lithium batteries. First, LVO operates at an average potential of 0.6V vs. Li/Li + , well above the Li-metal plating region allowing ultrafast charge capability without sacrificing safety. Second, the LVO has a high specific capacity of 250 mAh/g making battery pack energy density equivalent with current high-energy Li-ion chemistries.

25 ENERGY STORAGE↗
NASA NTRS1978

Photoelectrolysis of water at high current density - Use of laser light excitation of semiconductor-based photoelectrochemical cells

In the present paper, some results are given for UV laser light irradiation of the photoanode (SnO2, SrTiO3, or TiO2) in a cell for the light-driven electrolysis of H2O, at radiation intensities of up to 380 W/sq cm. The properties of the anode material are found to be independent of light intensity. Conversion of UV light to stored chemical energy in the form of 2H2/O2 from H2O was driven at a rate of up to 30 W/sq cm. High O2 evolution rates at the irradiated anodes without changes in the current-voltage curves are attributed to the excess oxidizing power associated with photogenerated holes. A test for this sort of hypothesis for H2 evolution at p-type materials is proposed.

Wrighton, M. S.↗
DOE OSTI2025

A Perspective on Pathways Toward Commercial Sodium‐Ion Batteries

Lithium-ion batteries (LIBs) have been widely adopted in the automotive industry, with an annual global production exceeding 1000 GWh. Despite their success, the escalating demand for LIBs has created concerns on supply chain issues related to key elements, such as lithium, cobalt, and nickel. Sodium-ion batteries (SIBs) are emerging as a promising alternative due to the high abundance and low cost of sodium and other raw materials. Nevertheless, the commercialization of SIBs, particularly for grid storage and automotive applications, faces significant hurdles. This perspective article aims to identify the critical challenges in making SIBs viable from both chemical and techno-economic perspectives. First, a brief comparison of the materials chemistry, working mechanisms, and cost between mainstream LIB systems and prospective SIB systems is provided. The intrinsic challenges of SIBs regarding storage stability, capacity utilization, cycle stability, calendar life, and safe operation of cathode, electrolyte, and anode materials are discussed. Furthermore, issues related to the scalability of material production, materials engineering feasibility, and energy-dense electrode design and fabrication are illustrated. Finally, promising pathways are listed and discussed toward achieving high-energy-density, stable, cost-effective SIBs.

25 ENERGY STORAGE↗
DOE OSTI2023

Polycarbonate‐Based Solid‐Polymer Electrolytes for Solid‐State Sodium Batteries

Solid-polymer electrolytes comprised of polypropylene carbonate (PPC) and varied sodium bis(fluorosulfonyl)imide (NaFSI) salt concentrations are investigated for implementation as a conductive solid polymer electrolyte into solid-state cathode composites utilizing a sodium-layered oxide active material. The ionic conductivity generally increases with NaFSI salt content, reaching ≈1 mS cm −1 at 80 °C at the highest salt concentration (PPC:NaFSI = 0.5:1). Through an all-in-one slurry casting method, Na 2/3 Ni 1/3 Mn 2/3 O 2 cathode composites are fabricated in which the dispersed PPC electrolyte acts as the primary binder. Enabled by a bilayer polymer electrolyte system, cycling performance with the PPC cathode electrolyte is optimized with respect to salt concentration and anode material. The best cyclability is achieved with a moderate salt concentration electrolyte (PPC:NaFSI = 5:1), showcasing an initial capacity of 83 mA h g −1 with a remarkable 80% capacity retention after 150 cycles at C/5 rate and 60 °C. The superior performance of the lower salt concentration electrolyte is attributed to better electrochemical stability, as confirmed by linear sweep voltammetry and online electrochemical mass spectrometry measurements. In conclusion, these results underscore the potential of carbonate-based polymer electrolytes and the importance of balancing electrolyte conductivity and stability in cell design.

25 ENERGY STORAGE↗
DOE OSTI2025

Resistive Switching of Spinel Li 4 Ti 5 O 12 Lithium-Ion Battery Material for Neuromorphic Computing

The rapid rise of AI has exposed significant limitations in conventional Von Neumann computing architecture, particularly in regard to speed and energy efficiency. To address these challenges, researchers are exploring a brain-inspired neuromorphic architecture that mimics biological neural networks, enabling massive parallel processing with reduced power consumption for complex AI computational demands. Recent interest has focused on utilizing battery electrodes and solid electrolyte materials for their resistive switching properties in developing a neuromorphic architecture. These properties are precisely tuned through local- and bulk-level chemical composition modifications via voltage bias stimuli. In this study, we demonstrate fabricating a three-terminal lithium-ion electrochemical transistor based on lithium titanium oxide (Li 4 Ti 5 O 12 ), a popular lithium-ion battery anode material. We deposited and characterized LTO thin films using RF sputtering, demonstrating a 6 orders of magnitude increase in electronic conductivity upon lithiation, with conductivity plateauing after 20% lithiation. Density functional theory calculations revealed transformation from the insulating to conducting state, supported by experimental characterization through X-Ray Photoelectron Spectroscopy (XPS) and Direct Current (DC) polarization analyses. The fabricated transistor consisted of LTO as the channel layer, gold as source/drain terminals, lithium phosphorus oxynitride (LiPON) as the lithium-ion conductor, and copper as the gate terminal. The device exhibited clear hysteresis in transfer characteristics due to lithium insertion/extraction processes. Long-term potentiation (LTP) and long-term depression (LTD) measurements showed an asymmetric ratio of 1.425 and maximum/minimum conductance ratio of 7.83. When implemented in a deep neural network (DNN) for MNIST handwritten digit recognition, the device achieved 92.03% accuracy over 20 training epochs. Detailed transport mechanism analysis revealed the crucial role of oxygen vacancies and interface effects in device operation. Our preliminary findings establish LTO-based lithium-ion electrochemical transistors as promising candidates for energy-efficient neuromorphic computing applications, offering potential solutions to traditional Von Neumann architecture limitations.

25 ENERGY STORAGE↗
DOE OSTI2025

Influence of surface chemistry on Li nucleation energetics on graphene-based surfaces

Lithium metal is a promising high-capacity anode material for solid-state batteries, but it typically suffers from poor cyclability. Carbon scaffold hosts have the potential to improve this performance due to their high electronic conductivity and large surface area, which facilitates lithium-ion adsorption and desorption. Scaffold surface chemistry is known to significantly influence performance outcomes, but the details of these interactions are not fully understood. Here, this study employs first-principles simulations to explore lithium transport and nucleation on graphene anodes with various surface chemistries. Using enhanced sampling techniques, ab initio molecular dynamics, and density functional theory calculations, we find that although surface chemistry has a minimal impact on lithium interfacial transport, it influences surface nucleation significantly. Both heteroatom dopants and intrinsic defects lower the nucleation barrier, creating a more favorable environment for lithium nucleation compared to pristine graphene. In addition, our results reveal a complex interplay between surface lithium concentration, lithium transport, and nucleation kinetics. These findings highlight the potential of surface modifications to precisely control nucleation processes on carbon-based anodes and provide design guidance for reducing dendrite formation and improving the cycle life of solid-state batteries.

36 MATERIALS SCIENCE↗