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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 55 records · Page 3
All sourcesNASA NTRSDOE OSTI
DOE OSTI2022

Toward practical issues: Identification and mitigation of the impurity effect in glyme solvents on the reversibility of Mg plating/stripping in Mg batteries

Reversible electrochemical magnesium plating/stripping processes are important for the development of high-energy-density Mg batteries based on Mg anodes. Ether glyme solutions such as monoglyme (G1), diglyme (G2), and triglyme (G3) with the MgTFSI 2 salt are one of the conventional and commonly used electrolytes that can obtain the reversible behavior of Mg electrodes. However, the electrolyte cathodic efficiency is argued to be limited due to the enormous parasitic reductive decomposition and passivation, which is governed by impurities. In this work, a systematic identification of the impurities in these systems and their effect on the Mg deposition–dissolution processes is reported. The mitigation methods generally used for eliminating impurities are evaluated, and their beneficial effects on the improved reactivity are also discussed. By comparing the performances, we proposed a necessary conditioning protocol that can be easy to handle and much safer toward the practical application of MgTFSI 2 /glyme electrolytes containing impurities.

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

Improving Interface Stability of Si Anodes by Mg Coating in Li-Ion Batteries

Silicon (Si) is a promising anode material for high-energy-density lithium-ion batteries (LIBs), but its short calendar life and poor cycling performance prevent its large-scale adoption. Introducing magnesium (Mg) salt into the electrolyte has been recently shown to form a ternary Li–Mg–Si Zintl phase upon lithiation of Si and improve the cycling performance. However, the ternary Zintl phase formation mechanism and its impact on the solid electrolyte interphase (SEI) are not yet well understood. In this work, we demonstrate the formation of a ternary Li–Mg–Si Zintl phase by Mg coating of the Si anode, where Mg diffuses into the Si film upon deposition and intermixes further during the lithiation process. The presence of the Zintl phase improves the interface stability, alters the nature of the SEI, and enhances the cycling performance of the Si anode. This study provides insights into the formation mechanism of the ternary Zintl phase and guidelines for the future design of Si anodes.

25 ENERGY STORAGE↗
NASA NTRS2017

Magnesium Alloys for Space Hardware Design

There have been advances in magnesium alloy development that NASA has not taken into consideration for space hardware because of a lack of test data. Magnesium alloys offer excellent weight reduction, specific strength, and deep space radiation mitigation. Traditionally, magnesium has been perceived as having too poor of a flammability resistance and corrosion resistance to be used for flight. Recent developments in magnesium alloying has led to the formation of two alloys, WE43 and Elektron 21, which are self-extinguishing and significantly less flammable because of their composition. Likewise, an anodizing process called Tagnite was formulated to deter any concern with galvanic and saltwater corrosion. The Materials Science Branch at Kennedy Space Center is currently researching these new alloys and treatments to better understand how they behave in the harsh environment of space. Successful completion of the proposed testing should result in a more thorough understanding of modern aerospace materials and processes, and possibly the permission to use magnesium alloys in future NASA designs.

microstructure↗
NASA NTRS1999

The Mars Environmental Compatibility Assessment (MECA) Wet Chemistry Experiment on the Mars 2001 Lander

The Mars Environmental Compatibility Assessment (MECA) is an instrument suite that will fly on the Mars Surveyor 2001 Lander Spacecraft. MECA is sponsored by the Human Exploration and Development of Space (HEDS) program and will evaluate potential hazards that the dust and soil of Mars might present to astronauts and their equipment on a future human mission to Mars. Four elements constitute the integrated MECA payload: a microscopy station, patch plates, an electrometer, and the wet chemistry laboratory (WCL). The WCL consists of four identical cells, each of which will evaluate a sample of Martian soil in water to determine conductivity, pH, redox potential, dissolved C02 and 02 levels, and concentrations of many soluble ions including sodium, potassium, magnesium, calcium and the halides. In addition, cyclic voltammetry will be used to evaluate reversible and irreversible oxidants present in the water/soil solution. Anodic stripping voltammetry will be used to measure concentrations of trace metals including lead, copper, and cadmium at ppb levels. Voltammetry is a general electrochemical technique that involves controlling the potential of an electrode while simultaneously measuring the current flowing at that electrode. The WCL experiments will provide information on the corrosivity and reactivity of the Martian soil, as well as on soluble components of the soil which might be toxic to human explorers. They will also guide HEDS scientists in the development of high fidelity Martian soil simulants. In the process of acquiring information relevant to HEDS, the WCL will assess the chemical composition and properties of the salts present in the Martian soil.

Grannan, S. M.↗
DOE OSTI2021

Self-discharge of magnesium–sulfur batteries leads to active material loss and poor shelf life

Due to its high theoretical energy density and relative abundancy of active materials, the magnesium–sulfur battery has attracted research attention in recent years. A closely related system, the lithium-sulfur battery, can suffer from serious self-discharge behavior. Until now, the self-discharge of Mg–S has been rarely addressed. Herein, we demonstrate for a wide variety of Mg–S electrolytes and conditions that Mg–S batteries also suffer from serious self-discharge. For a common Mg–S electrolyte, we identify a multi-step self-discharge pathway. Covalent S8 diffuses to the metal Mg anode and is converted to ionic Mg polysulfide in a non-faradaic reaction. Mg polysulfides in solution are found to be meta-stable, continuing to react and precipitate as solid magnesium polysulfide species during both storage and active use. Mg–S electrolytes from the early, middle, and state-of-the-art stages of the Mg–S literature are all found to enable the self-discharge. The self-discharge behavior is found to decrease first cycle discharge capacity by at least 32%, and in some cases up to 96%, indicating this is a phenomenon of the Mg–S chemistry that deserves focused attention.

25 ENERGY STORAGE↗
DOE OSTI2020

Ambient Temperature Graphitization Based on Mechanochemical Synthesis

Graphite has become a critical material because of its high supply risk and essential applications in energy industries. Its present synthesis still relies on an energy-intensive thermal treatment pathway (Acheson process) at about 3000 °C. Herein, a mechanochemical approach is demonstrated to afford highly crystalline graphite nanosheets at ambient temperature. The key to the success of our methodology lies in the successive decomposition and rearrangement of a carbon nitride framework driven by a denitriding reaction in the presence of magnesium. The afforded graphite features high crystallinity, a high degree of graphitization, a thin nanosheet architecture, and a small flake size, which endow it with superior efficiency in lithium-ion batteries as an anode material in terms of rate capacity and cycle stability. Finally, the mild and cost-effective pathway used in this study could be a promising alternative for graphite production.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
NASA NTRS1984

Atmospheric emissions photometric imaging experiment

The atmospheric emissions photometric imaging experiment was flown on Spacelab 1 to study faint natural and artificial atmospheric emission phenomena. The instrument imaged optical emission in the region 2000 to 7500 angstroms with a television system consisting of two optical channels, one wide-angle and one telephoto. A third optical channel imaged onto the photocathode of a microchannel plate photomultiplier tube that has 100 discrete anodes. A hand-held image intensifier camera with an objective grating permitted spectral analysis of the earth's airglow and the Shuttle glow. Preliminary data show magnesium ion emission features in the lower ionosphere as well as the spacecraft glow spectrum.

Mende, S. B.↗
DOE OSTI2023

Understanding the Effect of Electrochemical Properties and Microstructure on the Microgalvanic Corrosion of Mg Alloys via Phase-Field Simulations

In this work, we apply a phase-field model to gain insights into the corrosion behavior of Mg alloys. Specifically, we study the effect of electrochemical properties of the materials and their environment and the spatial distribution of second phases in a magnesium alloy. To this end, we perform sensitivity analyses in which we separately vary the exchange current density and corrosion potential of the second phase, as well as the electrolyte conductivity. We describe the effects of these parameters on the corrosion current and the resulting corrosion-front morphology. We also confirm that the ratio between the Wagner length, calculated for the anodic phase, and the initial width of the anodic domain is a good predictor of the morphological characteristic of the corroding surface. In addition, we examine the effect of the microstructure on the corrosion behavior in both 2D and 3D systems by varying the shape, size, and distribution of the second-phase regions. Our findings provide insights into the influence of the two-phase microstructure on the corrosion behavior in a magnesium alloy.

Electrochemistry↗
DOE OSTI2022

Fully Conjugated Poly(phthalocyanine) Scaffolds Derived from a Mechanochemical Approach Towards Enhanced Energy Storage

Phthalocyanines (Pc)-derived materials represent an attractive category of porous organic scaffolds featured by extensive π-conjugated networks, but their construction is still limited to the solution-based pathways, producing materials with inferior conductivity and porosity. Herein, a mechanochemistry-driven approach was developed leveraging the on-surface polymerization of aromatic nitrile monomers with ortho-positioned dicyano groups in the presence of metal catalysts (magnesium, zinc, or aluminum) under neat and ambient conditions. Diverse Pc-functionalized conjugated porous networks (Pc-CPNs) were obtained featured by extensively and fully π-conjugated skeletons, high surface areas, and hierarchical porosities. The monomers in this mechanochemical approach could be extended to those difficult to be handled in solution-based procedures. In this work, the Pc-CPNs displayed attractive electrochemical performance as supercapacitor and anodes in batteries, together with superb long-term stability.

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

A Cobalt– and Manganese–Free High–Nickel Layered Oxide Cathode for Long–Life, Safer Lithium–Ion Batteries

High-nickel LiNi 1–x–y Mn x Co y O 2 and LiNi 1–x–y Co x Al y O 2 cathodes are receiving growing attention due to the burgeoning demands on high-energy-density lithium-ion batteries. The presence of both cobalt and manganese in them, however, triggers multiple issues, including high cost, high toxicity, rapid surface deterioration, and severe transition-metal dissolution. Herein, a Co- and Mn-free ultrahigh-nickel LiNi 0.93 Al 0.05 Ti 0.01 Mg 0.01 O 2 (NATM) cathode that exhibits 82% capacity retention over 800 deep cycles in full cells, outperforming two representative high-Ni cathodes LiNi 0.94 Co 0.06 O 2 (NC, 52%) and LiNi 0.90 Mn 0.05 Co 0.05 O 2 (NMC, 60%) is presented. It is demonstrated that a titanium-enriched surface along with aluminum and magnesium as the stabilizing ions in NATM not only ameliorates unwanted side reactions with the electrolyte and structural disintegrity, but also mitigates transition-metal dissolution and active lithium loss on the graphite anode. As a result, the graphite anode paired with NATM displays an ultrathin (≈8 nm), monolayer anode-electrolyte interphase architecture after extensive cycling. Furthermore, NATM displays considerably enhanced thermal stability with an elevated exothermic temperature (213 °C for NATM vs 180 and 190 °C for NC and NMC, respectively) and remarkably reduced heat release. This work sheds light on rational compositional design to adopt ultrahigh-Ni cathodes in lithium-based batteries with low cost, long service life, and improved thermal stability.

25 ENERGY STORAGE↗
DOE OSTI2022

Cycling protocol for alkaline batteries

A method of operating a battery comprises discharging a cathode comprising manganese dioxide to within a 2nd electron capacity of the manganese dioxide at a C-rate of equal to or slower than C/10, recharging the battery, and cycling the battery during use a plurality of times. The cathode is in a battery, and the battery comprises the cathode, an anode, a separator disposed between the anode and the cathode, and an electrolyte. The cathode comprises the manganese dioxide and a conductive carbon. The anode comprises: a metal component and a conductive carbon. The metal component can be a metal, metal oxide, or metal hydroxide, and the metal of the metal component can be zinc, lithium, aluminum, magnesium, iron, cadmium and a combination thereof.

Kolhekar, Snehal↗
DOE OSTI2023

High capacity, air-stable, structurally isomorphous lithium alloy multilayer porous foams

The invention relates to composite multilayer lithium ion battery anodes that include a porous metal alloy foam, and a lithium ion conductor coating applied to the metal alloy foam. The metal alloy foam can include structurally isomorphous alloys of lithium and, optionally, lithium and magnesium. The lithium ion conductor coating can include ternary lithium silicate, such as, lithium orthosilicate. Lithium ions from the ternary lithium silicate may be deposited within the pores of the metal alloy foam. Optionally, the lithium ion conductor coating may include a dopant. The dopant can include one or more of magnesium, calcium, vanadium, niobium and fluorine, and mixtures and combinations thereof.

Kumta, Prashant N.↗
DOE OSTI2021

Metal alloy layers on substrates, methods of making same, and uses thereof

Metal alloy layers on substrates. The metal-alloy layers (e.g., lithium-metal layers, sodium-metal layers, and magnesium-metal layers) can be disposed on, for example, a solid-state electrolyte material. The metal-alloy layers can be used in, for example, solid-state batteries. A metal alloy layer can be an anode or part of an anode of a solid state battery.

Hu, Liangbing↗
DOE OSTI2020

Challenges and Development of Tin-Based Anode with High Volumetric Capacity for Li-Ion Batteries

Abstract The ever-increasing energy density needs for the mass deployment of electric vehicles bring challenges to batteries. Graphitic carbon must be replaced with a higher-capacity material for any significant advancement in the energy storage capability. Sn-based materials are strong candidates as the anode for the next-generation lithium-ion batteries due to their higher volumetric capacity and relatively low working potential. However, the volume change of Sn upon the Li insertion and extraction process results in a rapid deterioration in the capacity on cycling. Substantial effort has been made in the development of Sn-based materials. A SnCo alloy has been used, but is not economically viable. To minimize the use of Co, a series of Sn–Fe–C, Sn y Fe, Sn–C composites with excellent capacity retention and rate capability has been investigated. They show the proof of principle that alloys can achieve Coulombic efficiency of over 99.95% after the first few cycles. However, the initial Coulombic efficiency needs improvement. The development and application of tin-based materials in LIBs also provide useful guidelines for sodium-ion batteries, potassium-ion batteries, magnesium-ion batteries and calcium-ion batteries. Graphic Abstract

25 ENERGY STORAGE↗
DOE OSTI2022

Formation of carbon and oxygen rich surface layer on high purity magnesium by atmospheric carbon dioxide plasma

Carbon and oxygen-rich corrosion barrier layer formed on Mg by a simple and scalable CO 2 atmospheric plasma (CO 2 -AP) process. The reactive CO 2 -AP interacts with the Mg surface and forms a unique layered structure with the top MgCO 3 /MgO-intermixed particulates pillars and the bottom dense layer. The surface features were simultaneously formed on the nano-/micro-structured MgO layer by carbonate molecules, plasma-active CO 2 molecules, and/or other volatile organic compounds on the nano-/micro-structured MgO particle layer. The resulting surfaces after CO 2 -AP were either hydrophobic or hydrophilic and exhibited lower anodic current or high resistance for Mg corrosion. For the hydrophobic surfaces of CO 2 -AP treated Mg, molecular dynamic simulations were performed to understand the origin of hydrophobicity and identified that the amorphous carbon layers formed on the Mg surface are the source. The environmentally benign abundant-gas-based process enables the cost reduction associated with waste treatment, generation of by-product, and supply of raw material.

36 MATERIALS SCIENCE↗
DOE OSTI2020

The potential application of VS 2 as an electrode material for Mg ion battery: A DFT study

Herein, by means of first-principle calculations based on density functional theory (DFT), the electrochemical properties of monolayer VS 2 (M-VS 2 ), double-layer VS 2 (D-VS 2 ) and bulk VS 2 (B-VS 2 ) as electrode materials for Mg-ion batteries (MIBs) were comprehensively explored. The computation results reveal that Mg atom can strongly bind with the three different forms of VS 2 . All of the Mg adsorbed VS 2 systems demonstrate metallic characteristics, which indicates a good electronic conductivity. In addition, crystal orbital hamiltonian population shows that the stability of V-S bond is weakened after adsorption of Mg atom. The low diffusion barriers of Mg give rise to the high rate performance of VS 2 in MIBs. More interestingly, the three types of VS 2 display same storage ability for Mg cations, which can adsorb 0.5 Mg atoms for VS 2 , producing maximum theoretical capacity 233 mA h g -1 for MIBs. Furthermore, the average working voltages results suggest that M-VS 2 can be employed as anode materials, while D-VS 2 , B-VS 2 can be used as cathode materials for MIBs.

25 ENERGY STORAGE↗
DOE OSTI2025

Conjugation effect of amine molecules in non-aqueous Mg redox flow batteries

Nonaqueous magnesium redox flow batteries (Mg RFBs) are attractive for low-cost, high-energy-density and long-cycle-life stationary energy storage applications. However, state-of-the-art cathode redox-active molecules suffer from low solubility and low redox potential. Herein, we screened a range of cathode redox-active molecules and identified amine molecules as optimal to couple with the Mg anode. The properties of amine derivatives and their performances were collected to establish the correlation between molecular structures and electrochemical performances. The redox potential and solubility of these amine molecules were influenced by the π-conjugated and non-conjugated structures of amine derivatives. Density functional theory (DFT) simulations and the inverse aromatic fluctuation index (FLU −1 ) verified that conjugation had an important role in stabilizing the molecule and increasing its redox potential. Notably, tris[4-(diethylamino)phenyl]amine (TDPA) achieved the highest theoretical energy density (∼120 Wh L −1 ) due to its high solubility (∼0.9 M) and voltage (∼2.5 V vs. Mg/Mg 2+ ). We also demonstrated that ether solvents were crucial for stable, high-solubility catholytes, while bulk anions did not affect the redox potential of these p-type molecules. In a Mg-amine RFB configuration, the battery delivered 2.50 V, a specific discharge capacity of 106.5 mAh g −1 , an initial coulombic efficiency of 90.74%, and a capacity retention of 93.88% after 150 cycles.

Qin, Yunan [University of Utah, Salt Lake City, UT↗
DOE OSTI2023

Phase Field Modeling of Corrosion for Design of Next-Generation Magnesium-Aluminum Vehicle Joints

In this study, WPI and its partners sought to understand galvanic corrosion in Mg-Al friction stir weld (FSW) joints. Unlike fusion welds, FSW is done in the solid state. This limits (but does not eliminate) the formation of brittle Al-Mg intermetallics, resulting in better joint strength and corrosion resistance. This study aimed to understand corrosion behavior of Mg-Al FSW joints by using a Cahn-Hilliard phase field electrochemistry model based on the work of Pongsaksawad et al. Its context challenge problem was an ultra-light door designed by Magna with 6061-Al sheet outer and ZEK100-Mg sheet inner panels, joined by an adhesive and FSW. Unlike most FSW joints, which weld through the softer material into the harder one, the Al sheet’s hem joint around Mg required the FSW tool to through the harder Al into the softer Mg, which was itself a challenge. Despite this challenge, PNNL succeeded in consistently making very strong FSW lap joints, by using a triflute tool and power control. Characterization showed mostly separate Al and Mg regions in the weld, usually with a hook protruding from Al into Mg, which likely contributed to high joint strength. Nanohardness mapping showed higher hardness in thin Mg swirls into the Al nugget, likely due to the intermetallics. The study used the industry standard SAE J2334 Cyclic Corrosion Test (CCT) to simulate corrosion conditions over the life of a vehicle, as well as linear polarization testing and ASTM G71 pitting corrosion testing. Corrosion reactions were: H 2 O + ½O 2 + 2e - → 2OH - at the Al cathode, and either Mg → Mg 2+ + 2e - or Mg + 2OH - → Mg(OH) 2 + 2e - at the Mg anode, with electron transfer through the joint. Mass loss increased with Al section length, supporting the hypothesis that galvanic corrosion in Al-Mg joints is limited by the cathodic reaction. Both pitting corrosion (first anode reaction) and hydroxide film formation (second reaction) were observed. The J2334 CCT test method was slightly modified, adding a chromium solution cleaning step after each week of corrosion testing, in order to remove Mg oxides and hydroxides and accurately measure mass loss over time. That said, FSW joints treated in this way did not did not exhibit significant reduction in lap shear strength of the joints vs. newly welded samples which had not undergone corrosion. Corrosion appeared to consist mainly of pitting in Mg in a way which did not directly affect the bond between the materials where the joints failed. A Cahn-Hilliard phase field model coupled with electrical potential described the electronically mediated galvanic corrosion electrochemical reactions described above in the four-component Al-Mg-H 2 O-(H 2 O+½O 2 ) system. This 2-D model successfully predicted Mg(OH)₂ formation at the anode in some circumstances, and Mg pitting corrosion in others, and showed the correct electric field directions in both cases. The model predicted Mg pit corrosion depth within a factor of two of measured pits.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗