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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 1,675 records · Page 93
All sourcesNASA NTRSDOE OSTI
DOE OSTI2015

Compatibility of a Conventional Non-aqueous Magnesium Electrolyte with a High Voltage V 2 O 5 Cathode and Mg Anode

A major roadblock for magnesium ion battery development is the availability of an electrolyte that can deposit Mg reversibly and at the same time is compatible with a high voltage cathode. We report a prospective full magnesium cell utilizing a simple, non-aqueous electrolyte composed of high concentration magnesium bis(trifluoromethane sulfonyl)imide in diglyme, which is compatible with a high voltage vanadium pentoxide (V 2 O 5 ) cathode and a Mg metal anode. For this system, plating and stripping of Mg metal can be achieved with magnesium bis(trifluoromethane sulfonyl)imide in diglyme electrolyte over a wide concentration range, however, reversible insertion of Mg into V 2 O 5 cathode can only be attained at high electrolyte concentrations. Reversible intercalation of Mg into V 2 O 5 is characterized and confirmed by X-ray diffraction, X-ray absorption near edge spectroscopy and energy dispersive spectroscopy.

Sa, Niya↗
DOE OSTI2017

"Ion" B-Dot and Faraday Cup Results Located Inside The Cathode Knob Of The Self Magnetic Pinch (Smp) Diode (A New Diagnostic For Diode Behavior?)

This paper describes our effort to measure the back-streaming ions emitted from the target x-ray convertor and thus estimate the ion contribution to the A-K gap bipolar current flow. Knowing the ion contribution is quite important in order to calculate the expected x-ray dose and compare it with the actual measurements. Our plans were first to measure the total ion current using B-dot monitors, Rogowski coils, and Faraday cups and then to utilize filtered Faraday cups and time of flight techniques to identify and measure the various ionic species. The kinetic energy (velocities) of the ions should help evaluate the actual voltage applied at the anode-cathode (A-K) gap. LSP simulations found that the most prominent ions are protons and carbon single plus (C+). For an 8-MV A-K voltage, the estimated proton current back-streaming through an 1 cm in diameter hollow cathode tip was on the average 3 kA and the carbon current 0.7 kA. Since only a small fraction of the ions will make it through the cylindrical aperture, the corresponding total currents were calculated to be respectively 25kA for proton and 7 kA for carbon ions, a quite substantial contribution to the total bipolar beam current. Hence, approximately only 10% of the total back-streaming ionic currents could make it through the hollow cathode tip aperture. Unfortunately the diagnostic cables connecting the Faraday cup and the B-dot monitors to the screen room scopes experienced a large amount of charge pick-up that obliterated our effort to directly measure those relatively small currents. However, we succeeded in measuring those currents indirectly with activation techniques [Contribution of the back-streaming ions to the self-magnetic pinch (SMP) diode Current., M. G. Mazarakis, M. G. Mazarakis, M. E. Cuneo, S. D. Fournier, M. D. Johnston, M. L. Kiefer, J. J. Leckbee, D. S. Nielsen, B.V.Oliver, M. E. Sceiford, S. C. Simpson, T. J. Renk, C. L. Ruiz, T. J. Webb, and D. Ziska. Subitted for publication.]. In the following sections we present some typical cable pick-up results and also our efforts to verify that the observed “current” scope traces were indeed not ion currents but instead cable charge pic-up. Interestingly enough we also discovered that the appearance of those “currents” are in synchronism with the A-K gap impedance variation (decrease) and the MITL sheath current re-trapping. Hence those B-dots or Faraday cups could be utilized as diode behavior diagnostics.

Mazarakis, Michael G.↗
DOE OSTI2010

Influential fuel cell systems including effective cathodes and use with remediation efforts

Embodiments may include efficient fuel cell systems including an anode, a cathode, a lead-containing cathode catalyst, at least one proton exchange connector, and perhaps even an external circuit between the anode and the cathode. Other embodiments may include enhanced degradation of contaminants in environmental media such as perhaps petroleum hydrocarbon in groundwater with microbial fuel cells and the like.

30 DIRECT ENERGY CONVERSION↗
DOE OSTI2014

High voltage cathode material for Li-ion batteries

A cathode electrode material for use in rechargeable Li-ion batteries, based on the integration of two Li-based materials of NASICON- and Spinel-type structures, is described in the present invention. The structure and composition of the cathode can be described by a core material and a surface coating surrounding the core material, wherein the core of the cathode particle is of the formula LiMn2-xNixO4−δ (0.5≦x≦0 & 0≦δ≦1) and having a spinel crystal structure, the surface coating is of the formula Li1+xMxTi2-x(PO4)3 (M: is a trivalent cation, 0.5≧x≧0) having a NASICON-type crystal structure.

Hagh, Nader Marandian↗
DOE OSTI2019

Polyanthraquinone-based organic cathode for high-performance rechargeable magnesium-ion batteries

A rechargeable magnesium ion electrochemical cell comprising an anode, a cathode, and a non-aqueous magnesium electrolyte disposed between the anode and the cathode is described herein. The cathode comprises a redox-active anthraquinone-based polymer comprising one or more of 1,4-polyanthraquinone or 2,6-polyanthraquinone. Both 2,6-polyanthraquinone and 1,4-polyanthraquinone can operate with 1.5-2.0 V with above 100 mAh/g capacities at a reasonable rate, higher than the state-of-the-art Mg—Mg6S8 battery. More than 1000 cycles with very small capacity loss can be realized.

Liao, Chen↗
DOE OSTI2019

Ultrastable cathodes for lithium sulfur batteries

A cathode for a lithium-sulfur battery includes a copper-containing current collector, over which an active material layer is disposed. A method of producing the cathode is provided. A lithium-sulfur battery including the cathode provides improved capacity and cycleability.

Elam, Jeffrey W.↗
DOE OSTI2020

Dual conductor surface modified SOFC cathode particles and methods of making same

A novel method to produce ALD films disposed on powders is disclosed. Examples include the formation of a cobalt doped zirconia (CDZ), hafnia, and cobalt doped hafnia (CDH) films on lanthanum strontium cobalt iron oxide (LSCF) powder for solid oxide fuel cell cathodes. The coated powders are sintered into porous cathodes that have utility for preventing the migration of cations in the powder to the surface of the sintered cathode and/or other performance enhancing attributes.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2021

Li-substituted layered spinel cathode materials for sodium ion batteries

Systems, methods, and compositions are disclosed for a Li-substituted layered-tunneled O3/spinel Na(NixFeyMnz)O2 cathode material, Na0.87Li0.25Ni0.4Fe0.2Mn0.4O2+∂ (LS-NFM) for enhanced sodium ion storage and cycling stability. The LS-NFM electrode is prepared by adjusting the stoichiometric ratio of the Na ion over the sum of Li and transition metal ions below 1. The Rietveld refinement of XRD data indicates that the cathode is composed of 94% layered and 6% spinel components. When cycled at a high current density of 100 mA g−1, LS-NFM cathode exhibited a first-cycle Coulombic efficiency of 88% and reversible discharge capacity of 107 mAh g−1 after 50 cycles with the capacity retention of 95%.

Xiong, Hui↗
DOE OSTI2022

Next-Generation Cobalt-Free Cathodes – A Prospective Solution to the Battery Industry's Cobalt Problem*

Lithium-ion batteries are over-reliant on cobalt-containing cathodes. Current projections estimate hundreds of millions of electric vehicles (EVs) will be on the road by 2050, and this ever-growing demand threatens to deplete global cobalt reserves at an alarming rate. Moreover, cobalt supply-chain issues have significantly increased cobalt prices throughout the last decade. As such, energy storage research and development need to reduce reliance on cobalt to meet ever-growing demands for lithium-ion batteries. This chapter summarizes the science/technology gaps and potential of numerous cobalt-free Li-ion cathodes, including layered, spinel, olivine, and disordered rocksalt systems. Despite the promising performance of these Co-free cathodes, scale-up and manufacturing bottlenecks associated with these materials must also be addressed to enable widespread adoption in commercial batteries. Overall, this review broadly highlights the enormous promise of “zero-cobalt” Li-ion batteries to enable sustainable production of EVs in the coming decades.

Muralidharan, Nitin↗
DOE OSTI2022

Stabilized birnessite cathode for high power and high energy density applications

A battery comprises a housing, an electrolyte disposed in the housing, an anode disposed in the housing, a stabilized cathode disposed in the housing and comprising a cathode material. The cathode material comprises a composition selected from birnessite or layered-polymorph of manganese dioxide (δ-MnO2), the composition being stabilized by bismuth and copper ions, a conductive carbon, and a binder. The anode can be at least 50% (m/m) lithium, magnesium, aluminum, or zinc.

Yadav, Gautam G.↗
DOE OSTI2022

Carbon dioxide treatment of cathodes

A method for producing water resistant cathodes is discussed. The method uses mixing cathode powder with solid carbon dioxide to create a mixture and heating the mixture to a temperature. The heating occurs for a time sufficient to cause lithium carbonate coatings to form on the powder. A method for coating lithium-containing cathode surfaces is also discussed. This method uses simultaneously sublimating solid CO 2 and condensing atmospheric water vapor onto surfaces. Afterwards allowing the lithium to react with the sublimated CO 2 for a time sufficient to create a lithium carbonate film on the surface.

Kahvecioglu, Ozgenur↗
DOE OSTI2023

Coatings for cathode active materials

A cathode active material includes a plurality of cathode active compound particles and a coating disposed over each of the cathode active compound particles. The coating includes a lithium (Li)-ion conducting oxide containing lanthanum (La) and titanium (Ti).

Wu, Huiming↗
DOE OSTI2023

Demarcating the Impact of Electrolytes on High–Nickel Cathodes and Lithium–Metal Anode

The ever-growing demand for low-cost, high-energy-density lithium-ion batteries (LIBs) makes high-nickel layered oxide cathodes, especially LiNiO 2 (LNO), one of the most appealing candidates. However, poor structural and surface instability that leads to a short cycle life remains a formidable challenge. Herein, a systematic investigation of LNO performance in two different electrolytes (a conventional carbonate-based LP57 electrolyte and an ether-based localized high-concentration electrolyte (LHCE)) with different charge cut-off voltages is presented. These findings show that the cathode-electrolyte reactivity is the main factor dictating the performance degradation of LNO at high voltages rather than bulk integrity. While LHCE can provide good stability beyond 4.2 V with a robust, uniform solid–electrolyte interphase (SEI) layer on the Li-metal anode, there is no significant difference in cyclability at 4.15 V (96% capacity retention after 200 cycles) for both LP57 and LHCE. From LNO symmetric cells, carbonate-based electrolyte is found to be good for LNO stability while ether-based electrolyte is beneficial toward Li-metal anode. Furthermore, a suitable electrolyte or a low cut-off voltage is necessary to maintain a decent cycle life. Altogether, this work highlights the impact of electrolyte and cut-off voltage on LNO and Li-metal, which can help guide the development of cells based on LNO.

25 ENERGY STORAGE↗
DOE OSTI2020

Kinetic Limitations in Single-Crystal High-Nickel Cathodes

High-nickel cathodes attract immense interest for use in lithium-ion batteries, to boost Li-storage capacity while reducing cost. For overcoming the intergranular-cracking issue in polycrystals, single-crystals are considered an appealing alternative, but aggravating concerns on compromising the electrochemical kinetics of electrodes. We report here a quantitative assessment of electrochemical reaction in single-crystal LiNi 0.8 Mn 0.1 Co 0.8 O 2 using operando hard X-ray microscopy/spectroscopy, revealing a strong dependence of redox kinetics on the state of charge (SOC) - being sluggish at low SOC while increasing rapidly as SOC increases both in the bulk electrode and individual particles. The observation is corroborated by transport measurements and finite-element simulation, indicating that the sluggish kinetics in single-crystals is governed by ionic transport at low SOC and may be alleviated through synergistic interaction with polycrystals integrated into a same electrode. Finally, with the elucidated mechanistic origin and alleviation solution of kinetic limitations in single-crystal high-Ni cathodes, this work constitutes a step forward in enabling their practical deployment.

25 ENERGY STORAGE↗
DOE OSTI2024

In situ Synchrotron X‐ray Metrology Boosted by Automated Data Analysis for Real‐time Monitoring of Cathode Calcination

Abstract Synchrotron X‐ray‐based in situ metrology is advantageous for monitoring the synthesis of battery materials, offering high throughput, high spatial and temporal resolution, and chemical sensitivity. However, the rapid generation of massive data poses a challenge to on‐site, on‐the‐fly analysis needed for real‐time process monitoring. Here, a weighted lagged cross‐correlation (WLCC) similarity approach is presented for automated data analysis, which merges with in situ synchrotron X‐ray diffraction metrology to monitor the calcination process of the archetypal nickel‐based cathode, LiNiO 2 . The WLCC approach, incorporating variables that account for peak shifts and width changes associated with structural transformations, enables rapid extraction of phase progression within 10 seconds from tens of diffraction patterns. Details are captured, from initial precursors to intermediates and the final layered LiNiO 2 , providing information for agile on‐site adjustments during experiments and complementing post hoc diffraction analysis by offering insights into early‐stage phase nucleation and growth. Expanding this data‐powered platform paves the way for real time calcination process monitoring and control, which is pivotal to quality control in battery cathode manufacturing.

36 MATERIALS SCIENCE↗
DOE OSTI2019

On the Use of Voltammetry to Estimate the Effectiveness of Cathodic Protection of Buried Steel Structures

Buried steel structures, e.g., oil and gas pipelines, are often protected against corrosion by the combination of organic coating and cathodic protection. The effectiveness of cathodic protection can be monitored over time using voltammetry via a computer fitting of the polarization curves with theoretical electrochemical kinetic laws. In this study, the influence of the scan rate and the procedure used for the acquisition of the polarization curve was investigated. Reliable, though slightly overestimated, residual corrosion rates were obtained using a specific procedure and a low potential scan rate. However, the residual corrosion rate has a meaning only if the wet area of the electrode is known, which can be achieved by measuring another parameter linked to the wet area, e.g., the electrolyte resistance R{sub s}. In a soil at 25% saturation, the wet area, which is the surface of the metal in contact with the soil electrolyte, may be actually significantly different from the whole surface of the electrode.

36 MATERIALS SCIENCE↗
DOE OSTI2011

Hybrid CFx–Ag2V4O11 as a high-energy, power density cathode for application in an underwater acoustic microtransmitter

This study demonstrates the excellent electrochemical performance of the hybrid carbon fluoride(CFx)/silver vanadium oxide(SVO)/graphene(G) cathode and its potential utilization in Acoustic Telemetry System Transmitter (ATST). The impedance increase issue caused by LiF formation from CFx is effectively addressed by the deposition of conductive silver metal from the reduction of SVO aided by the coexistence of graphene additive thus a prolonged operation voltage is observed with enhanced electronic conductivity throughout the whole discharge process. In particular, the hybrid shows capacity retention of {approx}462 mAhg-1 at 5C rate and 661 mAhg-1 at 1C rate. The peak current delivered from the as-designed hybrid cathode is improved compared with that of commercial Zn/Ag2O batteries suggesting the possibility of the further reduction on the size/weight of the micro batteries which is critical for the transmitters.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗