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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 73 records · Page 4
All sourcesNASA NTRSDOE OSTI
DOE OSTI2016

Controlled synthesis of MnOOH multilayer nanowires as anode materials for lithium-ion batteries

MnOOH multilayer nanowires have been successfully synthesized by a hydrothermal method. It is found that the uniform multilayer structure of nanowires ran through the entire nanowire, which is formed via a layer by layer. The electrochemical properties of MnOOH multilayer nanowires as an anode material for Li-ion batteries (LIB) were investigated, and excellent capacity retention, superior cycling performance, and high rate capability were achieved. Specifically, the reversible capacity of MnOOH multilayer nanowires is 521 mAh/g after 500 cycles at 0.1 C, with excellent electrochemical stability. The multilayer nanowire electrodes exhibit short electron path lengths, high internal dislocation densities and large surface to volume ratio, resulting in increased specific capacity, cycling stability and rate performance in the energy storage devices, which serves as an indication of their potential application in LIBs. - Highlights: •MnOOH multilayer nanowires were synthesized by a hydrothermal method. •The uniform multilayer structure of nanowires was formed via layer by layer. •The reversible capacity of product shows 521 mAh/g after 500 cycles at 0.1 C. •MnOOH multilayer nanowires showed higher property as anode material in LIB.

36 MATERIALS SCIENCE↗
DOE OSTI2018

A Combined Experimental and Theoretical Study of Lithiation Mechanism in ZnFe2O4 Anode Materials

ABSTRACT ZnFe 2 O 4 (ZFO) represents a promising anode material for lithium ion batteries, but there is still a lack of deep understanding of the fundamental reduction mechanism associated with this material. In this paper, the complete visualization of reduction/oxidation products irrespective of their crystallinity was achieved experimentally through a compilation of in situ X-ray diffraction, synchrotron based powder diffraction, and ex-situ X-ray absorption fine structure data. Complementary theoretical modelling study further shed light upon the fundamental understanding of the lithiation mechanism, especially at the early stage from ZnFe 2 O 4 up to Li x ZnFe 2 O 4 (x = 2).

36 MATERIALS SCIENCE↗
DOE OSTI2020

A 3D porous honeycomb carbon as Na-ion battery anode material with high capacity, excellent rate performance, and robust stability

Motivated by the synthesis of three-dimensional (3D) honeycomb carbon structures and the subsequent theoretical prediction of an energetically more favorable hexagonal carbon phase composed of 28 carbon atoms in the unit cell (hC28) with ordered pores, excellent mechanical properties, and metallic feature, we explore its potential for a Na-ion battery (NIB) anode material. Using density functional theory based calculations, we find that hC28 is a promising candidate whose specific capacity of 717 mAh/g is almost three times larger than that of hard carbon (~250 mAh/g). In addition, migration barrier of Na ions along the honeycomb channel is only 0.08 eV and the volume change during the charging/discharging process is merely 2.30%, which are much less than those of other carbon-based NIB anode materials. The average voltage is also low (0.36 eV) which can provide high operating voltage when connected to the cathode. Finally, these encouraging results would pave the way towards the development of hC28 as NIB anode with high capacity, excellent rate performance, low open-circuit voltage, and long-term cycle life.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Chromate based ceramic anode materials for solid oxide fuel cells

The disclosure relates to solid oxide fuel cell (SOFC) anode materials that comprise various compositions of chromate based oxide materials. These materials offer high conductivity achievable at intermediate and low temperatures and can be used to prepare the anode layer of a SOFC. A method of making a low- or intermediate-temperature SOFC having an anode layer comprising a chromate based oxide material is also provided.

Abdul Jabbar, Mohammed Hussain↗
DOE OSTI2022

Hydrogenated and Carbon-coated Na2Ti6O13 Nanowires as High-Rate Anode Materials for Lithium Ion Batteries

The main disadvantage for sodium titanate as an anode material for LIBs is its low electronic conductivity, resulting in poor rate capability. Several approaches have been taken in an attempt to improve the electronic conductivity of sodium/lithium titanate, such as electronic material coating/mixing, ionic doping, comminution, etc.; but as of yet there has been no uniform carbon coating reported on sodium titanate for LIBs. In this work, we detail a facile technique to create uniform thin carbon coating layers on Na2Ti6O13 nanowires (NTO-C). In addition, we also explored self-doped Ti3+ on carbon coated Na2Ti6O13 nanowires (H-NTO-C) in an effort to further improve its electronic conductivity. The detailed results of the synthesis, characterization, and electrochemical performance of the NTO-based materials (NTO, NTO-C and H-NTO-C) will be presented.

25 ENERGY STORAGE↗
NASA NTRS1991

Evaluation of lithium alloy anode materials for Li-TiS2 cells

A study was performed to select candidate lithium alloy anode materials and establish selection criteria. Some of the selected alloy materials were evaluated for their electrochemical properties and performance. This paper describes the criteria for the selection of alloys and the findings of the studies. Li-Si and Li-Cd alloys have been found to be unstable in the EC+2-MeTHF-based electrolyte. The Li-Al alloy system was found to be promising among the alloy systems studied in view of its stability and reversibility. Unfortunately, the large volume changes of LiAl alloys during charge/discharge cycling cause considerable 'exfoliation' of its active mass. This paper also describes ways how to address this problem. The rate of disintegration of this anode would probably be surpressed by the presence of an inert solid solution or a uniform distribution of precipitates within the grains of the active mass. It was discovered that the addition of a small quantity of Mn may improve the mechanical properties of LiAl. In an attempt to reduce the Li-Al alloy vs. Li voltage, it was observed that LiAlPb(0.1)Cd(0.3) material can be cycled at 1.5 mA/sq cm without exfoliation of the active mass.

Huang, C.-K.↗
DOE OSTI2022

Insight into the Fast-Rechargeability of a Novel Mo 1.5 W 1.5 Nb 14 O 44 Anode Material for High-Performance Lithium-Ion Batteries

Wadsley–Roth phased niobates are promising anode materials for lithium-ion batteries, while their inherently low electrical conductivity still limits their rate-capability. Herein, a novel doped Mo 1.5 W 1.5 Nb 14 O 44 (MWNO) material is facilely prepared via an ionothermal-synthesis-assisted doping strategy. The detailed crystal structure of MWNO is characterized by neutron powder diffraction and aberration corrected scanning transmission electron microscope, unveiling the full occupation of Mo 6+ -dopant at the t1 tetrahedral site. In half-cells, MWNO exhibits enhanced fast-rechargeability. In this work, the origin of the improved performance is investigated by ultraviolet–visible diffuse reflectance spectroscopy, density functional theory (DFT) computation, and electrochemical impedance spectroscopy, revealing that bandgap narrowing improves the electrical conductivity of MWNO. Furthermore, operando X-ray diffraction elucidates that MWNO exhibits a typical solid-solution phase conversion-based lithium-ion insertion/extraction mechanism with reversible structural evolution during the electrochemical reaction. The boosted lithium-ion diffusivity of MWNO, due to the Mo 6+ /W 6+ doping effect, is confirmed by a galvanostatic intermittent titration technique and DFT. With the simultaneously enhanced electrical conductivity and lithium-ion diffusivity, MWNO successfully demonstrates its fast-rechargeability and practicality in the LiNi 0.5 Mn 1.5 O 4 -coupled full-cells. Therefore, this work illustrates the potential of ionothermal synthesis in energy storage materials and provides a mechanistic understanding of the doping effect on improving material's electrochemical performance.

25 ENERGY STORAGE↗
DOE OSTI2017

Facile synthesis of MoO{sub 2}@C nanoflowers as anode materials for sodium-ion batteries

Graphical abstract: The as-obtained MoO{sub 2}@C nanoflowers deliver a reversible capacity of 172 mAh g{sup −1} at 0.1 A g{sup −1} and a capacity of 166 mA h g{sup −1} after 1000 cycles at 1.0 A g{sup −1}. - Highlights: • MoO{sub 2}@C nanoflowers are synthesized. • Irregular MoO{sub 2}@C nanoparticles are synthesized. • MoO{sub 2}@C nanoflowers deliver a reversible capacity of 172 mAh g{sup −1} at 0.1 A g{sup −1}. - Abstract: Sodium-ion batteries (NIBs) have been considered to be the promising alternative to lithium-ion batteries (LIBs) due to the limited availability and uneven distribution of lithium resources. The exploration of anode materials for SIBs was still limited, and transition metal oxides (TMOs) have been widely studied for a long time. MoO{sub 2}@C nanoflowers were synthesized through a grinding method, followed by an annealing process. In addition, irregular MoO{sub 2}@C nanoparticles could be synthesized, when the amount of ammonium molybdate was increased by twice while other condition kept the same. With excellent dispersity and structural integrity, the as-obtained MoO{sub 2}@C nanoflowers deliver a reversible capacity of 172 mAh g{sup −1} at 0.1 A g{sup −1} and a capacity of 166 mA h g{sup −1} after 1000 cycles at 1.0 A g{sup −1}.

36 MATERIALS SCIENCE↗
DOE OSTI2021

MnSn 2 and MnSn 2 –TiO 2 nanostructured anode materials for lithium-ion batteries

The high theoretical lithium storage capacity of Sn makes it an enticing anode material for Li-ion batteries (LIBs); however, its large volumetric expansion during Li–Sn alloying must be addressed. Combining Sn with metals that are electrochemically inactive to lithium leads to intermetallics that can alleviate volumetric expansion issues and still enable high capacity. Here, we present the cycling behavior of a nanostructured MnSn 2 intermetallic used in LIBs. Nanostructured MnSn 2 is synthesized by reducing Sn and Mn salts using a hot injection method. The resulting MnSn 2 is characterized by x-ray diffraction and transmission electron microscopy and then is investigated as an anode for LIBs. The MnSn 2 electrode delivers a stable capacity of 514 mAh g -1 after 100 cycles at a C/10 current rate with a Coulombic efficiency >99%. Unlike other Sn-intermetallic anodes, an activation overpotential peak near 0.9 V versus Li is present from the second lithiation and in subsequent cycles. We hypothesize that this effect is likely due to electrolyte reactions with segregated Mn from MnSn 2 . To prevent these undesirable Mn reactions with the electrolyte, a 5 nm TiO 2 protection layer is applied onto the MnSn 2 electrode surface via atomic layer deposition. The TiO 2 -coated MnSn 2 electrodes do not exhibit the activation overpotential peak. The protection layer also increases the capacity to 612 mAh g -1 after 100 cycles at a C/10 current rate with a Coulombic efficiency >99%. This higher capacity is achieved by suppressing the parasitic reaction of Mn with the electrolyte, as is supported by x-ray photoelectron spectroscopy analysis.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2018

Understanding the electrochemical lithiation/delithiation process in the anode material for lithium ion batteries NiFeOPO 4 /C using ex-situ X-ray absorption near edge spectroscopy and in-situ synchrotron X-ray

Here, nickel iron (III) oxyphosphate NiFeOPO 4 (NFP) was successfully synthesized using solid-state route and modified with carbon layer using sucrose as carbon source. The electrochemical performances of the composite anode material NiFeOPO 4 /C (NFP/C) vs. Li + /Li 0 were investigated at C/5 current rate and in a wide voltage window 0.01-3.0 V. During the first lithiation at C/5, NFP/C was able to uptake more than six lithium ions into the structure delivering a capacity of 736.63 mAh g -1 . In this study, NFP phosphate was characterized using XRD, SEM, EDS mapping, and Raman spectroscopy. The first cycle was investigated using high energy spectroscopies including: in-situ synchrotron X-Ray Diffraction and ex-situ X-ray Absorption Near Edge Spectroscopy (XANES). In-situ synchrotron XRD revealed that the crystal structure of NFP/C undergoes structural transformations leading to lower degrees of crystallinity during the first lithiation. Ex-situ XANES measurements disclosed that the redox reaction of iron and nickel during the first lithiation and delithiation is reversible.

25 ENERGY STORAGE↗
DOE OSTI2018

Synthesis and Characterization of Li4Ti5O12 Anode Materials with Enhanced High-Rate Performance in Lithium-Ion Batteries

ABSTRACT Li 4 Ti 5 O 12 (LTO) represents a promising anode material for lithium ion batteries, however, it suffers from limitations associated with poor intrinsic electron conductivity as well as moderate ionic conductivity. Hence, to achieve the goal of creating LTO anodes with improved high-rate performance, we have put forth a number of targeted fundamental strategies. Herein we discuss the roles of controllably tuning (i) morphology, (ii) attachment modalities of carbon, and (iii) ion doping of the LTO material. In addition, we also demonstrated in situ studies of lithiation-driven structural transformations in LTO via a combination of X-ray absorption spectroscopy and ab initio calculations, which have been proven to be powerful tools to probe the negligible volume change and extraordinary stability of LTO upon repeated charge/discharge cycles.

energy storage (including batteries and capacitors↗
DOE OSTI2018

Synthesis of hierarchical 1D NiO assisted by microwave as anode material for lithium-ion batteries

Highlights: • Fast microwave solvothermal reaction is applied to obtain hierarchical 1 D NiO. • NiC{sub 2}O{sub 4}·2H{sub 2}O template forms within 30 min without any organic chelating agent. • High surface area of 208.8 m{sup 2} g{sup −1} is obtained due to the porous structure. • High initial capacity above 1000 mAh g{sup −1} is reached at 1.0 A g{sup −1}. • At 5.0 A g{sup −1}, high charge/discharge capacity of 574/611 mAh g{sup −1} is obtained. - Abstract: Fast solvothermal reaction assisted with microwave is performed to obtain hierarchical 1 D NiO with porous structure. First, the 1D NiC{sub 2}O{sub 4}·2H{sub 2}O precursor template grows within only 30 min without any other organic chelating agent. Then, a facile heat-treatment is carried out to get the final NiO through gas removal. High surface area of 208.8 m{sup 2} g{sup −1} is obtained due to the porous structure and small particle size of NiO. Thus, high initial charge/discharge capacity of 1020/1427 mAh g{sup −1} is obtained at 100 mA g{sup −1}. Even increasing the current density to 5.0 A g{sup −1}, high charge/discharge capacity of 574/611 mAh g{sup −1} can be obtained. Such good rate capability is attributed to the special hierarchical 1D structure which offers fast transfer of electrons and Li ions. Such facile strategy is considered as one of the most promising candidates to get anode material with remarkable electrochemical performances for application in lithium ion batteries.

36 MATERIALS SCIENCE↗
DOE OSTI2017

Role of calcination atmosphere in vanadium doped Li{sub 4}Ti{sub 5}O{sub 12} for lithium ion battery anode material

Highlights: • First comparison on V doped Li{sub 4}Ti{sub 5}O{sub 12} (VLTO) synthesized in air and argon. • Ti{sup 4+} do not reduce to Ti{sup 3+} in air calcined VLTO. • V doping enhances reducing of Ti{sup 4+} to Ti{sup 3+} in argon calcined VLTO. • Li{sub 4}Ti{sub 4.9}V{sub 0.1}O{sub 12} calcined in argon shows best charge-discharge behaviors. • Conductivity enhancement in argon calcined VLTO upto three orders. - Abstract: Li{sub 4}Ti{sub 5}O{sub 12} (LTO) with enhanced properties can replace the conventional carbonaceous anode material of lithium ion battery. Vanadium doped LTO (Li{sub 4}Ti{sub 5-x}V{sub x}O{sub 12}, x = 0, 0.05, 0.1, 0.15) materials are synthesized by sol-gel process followed by calcination of dried gel in air and argon atmosphere. No additional phase corresponding V is indicated in XRD patterns. Calcination in argon reduces the particle size of Li{sub 4}Ti{sub 5-x}V{sub x}O{sub 12} while V doping reduces particle size distribution. XPS reveals that Ti{sup 4+} get reduced to Ti{sup 3+} only in argon calcined Li{sub 4}Ti{sub 5-x}V{sub x}O{sub 12} which is enhanced by V doping. Electrochemical impedance spectroscopy confirms that compared to LTO, lithium ion diffusion coefficient of air and argon calcined Li{sub 4}Ti{sub 4.85}V{sub 0.15}O{sub 12} is approximately two and three times higher. Argon calcined Li{sub 4}Ti{sub 4.9}V{sub 0.1}O{sub 12} shows highest charge-discharge capacities at almost all C-rates (0.1 to 5C; 1C = 175mAg{sup −1}). Electronic conductivity of argon calcined Li{sub 4}Ti{sub 4.9}V{sub 0.1}O{sub 12} is 1.7 × 10{sup −2} S cm{sup −1} which is three orders higher than that of LTO.

36 MATERIALS SCIENCE↗
DOE OSTI2018

MnSb 2 S 4 Monolayer as an Anode Material for Metal-Ion Batteries

Here, we present density functional calculations showing that monolayer MnSb 2 S 4 is promising as an anode material for Li-, Na-, and Mg-ion batteries, and that the adsorption of Zn or Al atoms on the surface of MnSb 2 S 4 monolayer is not energetically favorable. The calculations show electron transfer from Li, Na, or Mg to the empty orbitals of nearby Sb and S atoms. The calculations indicate that an adsorption mechanism is followed by a conversion mechanism during charging, and the storage capacities can reach as high as 879 mA h/g for Li, Na, and Mg. The most favorable diffusion path for Li, Na, and Mg on the surface of MnSb2S4 monolayer is along the b direction; the lowest diffusion barriers for one Li, Na, and Mg are 0.18, 0.10, 0.32 eV, respectively. Good charge–discharge rates can be expected for the MnSb 2 S 4 monolayer when it is used as an electrode for Li-, Na-, and Mg-ion batteries.

25 ENERGY STORAGE↗
DOE OSTI2025

Multiscale electro-chemo-mechanical model of high-capacity amorphous silicon anode material in sodium-ion batteries

The growing interest in sodium-ion batteries (SIBs) is fueled by their abundant resources and environmentally friendly nature, with amorphous silicon (a-Si) emerging as a promising anode material for enhancing capacity. However, the key challenge lies in sustaining reversible capacity during cycling. Here, in this work, we developed a multiscale electrochemical model incorporating an a-Si anode to elucidate the performance parameters of SIBs. Additionally, we integrated an electro-chemo-mechanical model at the particle level to capture stress generation, an essential factor in the degradation of high-capacity electrodes. Unlike existing models, our approach accounts for large-deformation chemo-mechanics at the particle scale and includes simulations under varying charge rates to explore multiscale behavior. The results reveal that coupled sodiation significantly prolongs complete cycling times and influences discharge dynamics, indicating that neglecting this coupling leads to an underestimation of actual capacity. Furthermore, we observed pronounced polarization effects at higher charge rates, resulting in heterogeneous stress distributions across the anode. With the identification of critical failure parameters for both active particles and binder materials, offering novel insights for mitigating degradation in high-capacity electrode systems.

Amorphous silicon anode↗