Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “Li”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 397 records · Page 22

Screening of Li-Based Solid Electrolytes Using Bond-Valence Methods and Graph Neural Networks

Li-based solid-state electrolyte (Li-SSE) materials enable safer, all-solid-state batteries but the computational search for candidates with favorable stability and Li-ion conductivity is challenging due to the size of the search space and the cost of evaluating transport properties with ab initio methods. We present a high-throughput screening approach for Li-SSE materials using a combination of bond-valence methods and graph neural networks. We demonstrate the screening approach with a dataset containing tens of thousands of Li-containing compounds. Furthermore, we combine the machine-learning screening procedure with an isovalent substitution scheme to generate and screen additional Li SSE candidates beyond existing databases. Finally, we discuss relative importances of geometric and bond-valence quantities in the training of graph neural networks, providing insight for future modeling of ionic conductivity in Li-SSE materials.

Materials discovery↗

Distinct Dynamics of Lithium Intercalation and Plating on Graphite Anode for Li‐Ion Batteries in eVTOL Applications

In the absence of viable high-energy-density battery alternatives, lithium-ion (Li-ion) batteries remain essential for enabling electric vertical take-off and landing (eVTOL) platforms in advanced air mobility. Unlike Li-ion batteries used in electric vehicles and portable electronics, eVTOL battery systems operate under distinct high-power demands, which necessitate an independent assessment of material degradation mechanisms. This study presents a case analysis of graphite anode evolution under high-power cycling conditions. The findings reveal lithium entrapment within graphite particles, potentially resulting from incomplete Li-ion de-intercalation during a high-rate discharge event that is characteristic of eVTOL take-off and landing. This phenomenon leads to a progressive reduction in graphite-specific capacity and, over time, promotes lithium metal plating on the anode. Notably, the Li-metal plating observed in this study differs from that associated with fast-charging conditions, as it is primarily governed by concentration polarization-induced overpotential in the latter case. In conclusion, these findings highlight the inherent challenges of utilizing graphite in high-power Li-ion battery applications and elucidate the unique degradation mechanisms that arise due to the sluggish reaction kinetics of Li-ion intercalation and de-intercalation within graphite.

Li plating↗

Expandable Li Percolation Network: The Effects of Site Distortion in Cation-Disordered Rock-Salt Cathode Material

Cation-disordered rock-salt (DRX) materials receive intensive attention as a new class of cathode candidates for high-capacity lithium-ion batteries (LIBs). Unlike traditional layered cathode materials, DRX materials have a three-dimensional (3D) percolation network for Li + transportation. The disordered structure poses a grand challenge to a thorough understanding of the percolation network due to its multiscale complexity. In this work, we introduce the large supercell modeling for DRX material Li 1.16 Ti 0.37 Ni 0.37 Nb 0.10 O 2 (LTNNO) via the reverse Monte Carlo (RMC) method combined with neutron total scattering. Here, through a quantitative statistical analysis of the material’s local atomic environment, we experimentally verified the existence of short-range ordering (SRO) and uncovered an element-dependent behavior of transition metal (TM) site distortion. A displacement from the original octahedral site for Ti 4+ cations is pervasive throughout the DRX lattice. Density functional theory (DFT) calculations revealed that site distortions quantified by the centroid offsets could alter the migration barrier for Li + diffusion through the tetrahedral channels, which can expand the previously proposed theoretical percolating network of Li. The estimated accessible Li content is highly consistent with the observed charging capacity. The newly developed characterization method here uncovers the expandable nature of the Li percolation network in DRX materials, which may provide valuable guidelines for the design of superior DRX materials.

25 ENERGY STORAGE↗

Visualizing interfacial collective reaction behaviour of Li–S batteries

Benefiting from high energy density (2,600 Wh kg -1 )) and low cost, lithium-sulfur (Li-S) batteries are considered promising candidates for advanced energy-storage systems. Despite tremendous efforts in suppressing the long-standing shuttle effect of lithium polysulfides, understanding of the interfacial reactions of lithium polysulfides at the nanoscale remains elusive. This is mainly because of the limitations of in situ characterization tools in tracing the liquid-solid conversion of unstable lithium polysulfides at high temporal-spatial resolution. There is an urgent need to understand the coupled phenomena inside Li-S batteries, specifically, the dynamic distribution, aggregation, deposition and dissolution of lithium polysulfides. Here, by using in situ liquid-cell electrochemical transmission electron microscopy, we directly visualized the transformation of lithium polysulfides over electrode surfaces at the atomic scale. Notably, an unexpected gathering-induced collective charge transfer of lithium polysulfides was captured on the nanocluster active-centre-immobilized surface. It further induced an instantaneous deposition of nonequilibrium Li2S nanocrystals from the dense liquid phase of lithium polysulfides. Without mediation of active centres, the reactions followed a classical single-molecule pathway, lithium polysulfides transforming into Li 2 S 2 and Li 2 S step by step. Molecular dynamics simulations indicated that the long-range electrostatic interaction between active centres and lithium polysulfides promoted the formation of a dense phase consisting of Li + and S n 2- (2 < n ≤ 6), and the collective charge transfer in the dense phase was further verified by ab initio molecular dynamics simulations. Finally, the collective interfacial reaction pathway unveils a new transformation mechanism and deepens the fundamental understanding of Li-S batteries.

25 ENERGY STORAGE↗

Materials Data on Li(CO)2 by Materials Project

Li(CO)2 crystallizes in the monoclinic C2/m space group. The structure is one-dimensional and consists of two Li(CO)2 ribbons oriented in the (0, 0, 1) direction. Li is bonded to four O atoms to form a mixture of edge and corner-sharing LiO4 tetrahedra. There are two shorter (1.98 Å) and two longer (2.02 Å) Li–O bond lengths. There are two inequivalent C sites. In the first C site, C is bonded in a distorted single-bond geometry to one O atom. The C–O bond length is 1.27 Å. In the second C site, C is bonded in a distorted single-bond geometry to one O atom. The C–O bond length is 1.26 Å. There are two inequivalent O sites. In the first O site, O is bonded in a distorted T-shaped geometry to two equivalent Li and one C atom. In the second O site, O is bonded in a trigonal planar geometry to two equivalent Li and one C atom.

36 MATERIALS SCIENCE↗

Materials Data on Li(Sn3Pd)2 by Materials Project

Li(PdSn3)2 is Khatyrkite-derived structured and crystallizes in the tetragonal P4/mbm space group. The structure is three-dimensional. Li is bonded in a distorted q6 geometry to two equivalent Pd and eight equivalent Sn atoms. Both Li–Pd bond lengths are 2.85 Å. All Li–Sn bond lengths are 2.99 Å. Pd is bonded in a 9-coordinate geometry to one Li and eight Sn atoms. There are four shorter (2.82 Å) and four longer (2.97 Å) Pd–Sn bond lengths. There are two inequivalent Sn sites. In the first Sn site, Sn is bonded in a 7-coordinate geometry to four equivalent Pd atoms. In the second Sn site, Sn is bonded in a 4-coordinate geometry to two equivalent Li and two equivalent Pd atoms.

36 MATERIALS SCIENCE↗

Materials Data on Li(Mg4Al3)4 by Materials Project

Li(Mg4Al3)4 crystallizes in the cubic I-43m space group. The structure is three-dimensional. Li is bonded in a 4-coordinate geometry to four equivalent Mg and twelve equivalent Al atoms. All Li–Mg bond lengths are 3.08 Å. All Li–Al bond lengths are 3.21 Å. There are two inequivalent Mg sites. In the first Mg site, Mg is bonded in a 12-coordinate geometry to seven Mg and five equivalent Al atoms. There are a spread of Mg–Mg bond distances ranging from 3.06–3.16 Å. There are a spread of Mg–Al bond distances ranging from 2.90–3.16 Å. In the second Mg site, Mg is bonded in a 10-coordinate geometry to one Li, three equivalent Mg, and six equivalent Al atoms. All Mg–Al bond lengths are 3.07 Å. Al is bonded in a 11-coordinate geometry to one Li, seven Mg, and three equivalent Al atoms. There are one shorter (2.70 Å) and two longer (2.77 Å) Al–Al bond lengths.

36 MATERIALS SCIENCE↗

Materials Data on Li(ErGe)4 by Materials Project

Li(ErGe)4 is delta Molybdenum Boride-derived structured and crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Li is bonded in a 3-coordinate geometry to five Ge atoms. There are a spread of Li–Ge bond distances ranging from 2.68–3.13 Å. There are two inequivalent Er sites. In the first Er site, Er is bonded in a 6-coordinate geometry to six Ge atoms. There are a spread of Er–Ge bond distances ranging from 2.83–3.01 Å. In the second Er site, Er is bonded in a 7-coordinate geometry to seven Ge atoms. There are a spread of Er–Ge bond distances ranging from 2.95–3.35 Å. There are three inequivalent Ge sites. In the first Ge site, Ge is bonded in a 1-coordinate geometry to one Li, six Er, and one Ge atom. The Ge–Ge bond length is 2.56 Å. In the second Ge site, Ge is bonded in a 9-coordinate geometry to two equivalent Li, six Er, and one Ge atom. In the third Ge site, Ge is bonded in a 9-coordinate geometry to one Li, seven Er, and one Ge atom. The Ge–Ge bond length is 2.66 Å.

36 MATERIALS SCIENCE↗

Materials Data on Li(BH)6 by Materials Project

Li(BH)6 crystallizes in the cubic Pa-3 space group. The structure is zero-dimensional and consists of eight Li(BH)6 clusters. Li is bonded in a distorted octahedral geometry to six H atoms. There are three shorter (2.09 Å) and three longer (2.24 Å) Li–H bond lengths. There are two inequivalent B sites. In the first B site, B is bonded in a single-bond geometry to one H atom. The B–H bond length is 1.21 Å. In the second B site, B is bonded in a single-bond geometry to one H atom. The B–H bond length is 1.20 Å. There are two inequivalent H sites. In the first H site, H is bonded in a distorted water-like geometry to one Li and one B atom. In the second H site, H is bonded in a water-like geometry to one Li and one B atom.

36 MATERIALS SCIENCE↗

Materials Data on Li(YGe)4 by Materials Project

Li(YGe)4 is delta Molybdenum Boride-derived structured and crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Li is bonded in a distorted T-shaped geometry to five Ge atoms. There are a spread of Li–Ge bond distances ranging from 2.71–3.17 Å. There are two inequivalent Y sites. In the first Y site, Y is bonded in a 6-coordinate geometry to six Ge atoms. There are a spread of Y–Ge bond distances ranging from 2.87–3.04 Å. In the second Y site, Y is bonded in a 7-coordinate geometry to seven Ge atoms. There are a spread of Y–Ge bond distances ranging from 2.99–3.40 Å. There are three inequivalent Ge sites. In the first Ge site, Ge is bonded in a 8-coordinate geometry to one Li, six Y, and one Ge atom. The Ge–Ge bond length is 2.57 Å. In the second Ge site, Ge is bonded in a 9-coordinate geometry to two equivalent Li, six Y, and one Ge atom. In the third Ge site, Ge is bonded in a 9-coordinate geometry to one Li, seven Y, and one Ge atom. The Ge–Ge bond length is 2.68 Å.

36 MATERIALS SCIENCE↗

Materials Data on Li(LuGe)4 by Materials Project

Li(LuGe)4 is delta Molybdenum Boride-derived structured and crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Li is bonded in a 3-coordinate geometry to five Ge atoms. There are a spread of Li–Ge bond distances ranging from 2.65–3.09 Å. There are two inequivalent Lu sites. In the first Lu site, Lu is bonded in a 6-coordinate geometry to six Ge atoms. There are a spread of Lu–Ge bond distances ranging from 2.79–2.98 Å. In the second Lu site, Lu is bonded in a 7-coordinate geometry to seven Ge atoms. There are a spread of Lu–Ge bond distances ranging from 2.91–3.30 Å. There are three inequivalent Ge sites. In the first Ge site, Ge is bonded in a 1-coordinate geometry to one Li, six Lu, and one Ge atom. The Ge–Ge bond length is 2.56 Å. In the second Ge site, Ge is bonded in a 9-coordinate geometry to two equivalent Li, six Lu, and one Ge atom. In the third Ge site, Ge is bonded in a 9-coordinate geometry to one Li, seven Lu, and one Ge atom. The Ge–Ge bond length is 2.66 Å.

36 MATERIALS SCIENCE↗

An Ultra-long Life, High-performance, Flexible Li-CO2Battery Based on Multifunctional Carbon Electrocatalysts

Integrating CO2 utilization and renewable energy delivery/storage, the rechargeable Li–CO2 battery has been considered as a promising candidate for next-generation secondary batteries. However, high-performance catalyst(s) for efficient formation and decomposition of the discharge product, Li2CO3, are an imperative part of a Li–CO2 battery. The development of flexible Li–CO2 batteries extends their applications into compliant and wearable devices/systems, but at the same time imposes a big challenge for battery fabrication and lifetime enhancement. In this study, a rechargeable quasi-solidus flexible Li–CO2 battery was designed and fabricated using highly active N,S-doped carbon nanotubes (N,S-doped CNTs) as the cathode catalyst, and a smart polymer gel as the flexible electrolyte. This newly-developed flexible Li–CO2 battery exhibited a capacity as high as 23560 mAh g−1 based on the catalyst mass and an ultra-long lifetime of up to 538 cycles with excellent mechanical flexibility. This work provides a platform for the design and development of high-performance flexible Li–CO2 batteries from low-cost, earth-abundant, carbon-based multifunctional cathode catalysts.

Superior stability↗

Li 2 S 6 ‐Integrated PEO‐Based Polymer Electrolytes for All‐Solid‐State Lithium‐Metal Batteries

Abstract The integration of Li 2 S 6 within a poly(ethylene oxide) (PEO)‐based polymer electrolyte is demonstrated to improve the polymer electrolyte's ionic conductivity because the strong interplay between O 2− (PEO) and Li + from Li 2 S 6 reduces the crystalline volume within the PEO. The Li/electrolyte interface is stabilized by the in situ formation of an ultra‐thin Li 2 S/Li 2 S 2 layer via the reaction between Li 2 S 6 and lithium metal, which increases the ionic transport at the interface and suppresses lithium dendrite growth. A symmetric Li/Li cell with the Li 2 S 6 ‐integrated composite electrolyte has excellent cyclability and a high critical current density of 0.9 mA cm −2 at 40 °C. Impressive electrochemical performance is demonstrated with all‐solid‐state Li/LiFePO 4 and high‐voltage Li/LiNi 0.8 Mn 0.1 Co 0.1 O 2 cells at 40 °C.

Fang, Ruyi↗

Gallium‐Doping Effects on Structure, Lithium‐Conduction, and Thermochemical Stability of Li 7‐3 x Ga x La 3 Zr 2 O 12 Garnet‐Type Electrolytes

Abstract One of the most promising electrolytes for all‐solid‐state lithium batteries is Li 7 La 3 Zr 2 O 12 . Previously, their thermodynamic stability, Li‐ion conductivity, and structural features induced by Ga‐doping have not been empirically determined or correlated. Here, their interplay was examined for Li 7−3 x Ga x La 3 Zr 2 O 12 with target x Ga=0, 0.25, 0.50, 0.75, and 1.00 atoms per formula unit (apfu). Formation enthalpies, obtained with calorimetry and found to be exothermic at all compositions, linearly decreased in stability with increased x Ga. At dilute x Ga substitution, the formation enthalpy curve shifted stepwise endothermically, and the conductivity increased to a maximum, coinciding with 0.529 Ga apfu. This correlated with percolation threshold analysis (0.558 Ga apfu). Further substitution (0.787 Ga apfu) produced a large decrease in the stability and conductivity due to a large increase in point defects and blocked Li‐migration pathways. At x Ga=1.140 apfu, a small exothermic shift was related to defect cluster organization extending the Li hopping distance and decreased Li‐ion conductivity.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

First-principles analysis of the Al-rich corner of Al-Li-Cu phase diagram

The phase diagram of Al-Li-Cu system in the Al-rich region was determined by means of first-principles calculations and statistical mechanics. The mixing enthalpies of many configurations for different lattices in the whole Al-Li-Cu system were determined by density functional theory simulations to find the stable phases in the convex hull. They were fitted with a cluster expansion to calculate the free energy of the configurations with different compositions as a function of temperature in the Al-rich region (Al content > 40 at.%) by means of Monte Carlo simulations. It was found that the ground state phases in the Al-rich part of the Al-Li-Cu phase diagram were α-Al, θ' (Al 2 Cu), $δ$' (Al 3 Li), $δ$ (AlLi) and T 1 (Al 6 Cu 4 Li 3 ), while θ'' (Al 3 Cu), T 1' (Al 2 CuLi) and Al 3 Cu 2 Li were found on the lowest mixing enthalpy surfaces of their lattices and were metastable. α-Al, $δ$ and T 1 are stable phases in the whole temperature range while $δ$' becomes metastable at very low temperature and θ (Al 2 Cu) replaces θ' as the stable phase at approximately 550 K due to the vibrational entropic contribution. In addition, the phase diagram in the Al-rich region was built and it was shown in isothermal sections from 100 to 900 K. They were in good agreement with the limited experimental data in the literature and provided new information regarding the stability, solubility and stoichiometry of the different phases. This information is important to understand the precipitation mechanisms during high temperature aging.

36 MATERIALS SCIENCE↗

In-situ formation of stable interface towards Li-in anode for halide solid-state electrolyte

Halide-based solid-state electrolytes (SSEs) are promising candidates for next-generation all-solid-state lithium batteries (ASSLBs) due to their high ionic conductivity and chemical stability. However, their poor interfacial compatibility with lithium metal anode and Li-In alloy significantly hinder practical application due to the requirement for a protective interlayer. In this study, a novel approach to overcome this limitation is presented by introducing iron (Fe) doping into Li 3 InCl 6 (LIC), which enables direct and stable contact with lithium-indium (Li-In) metal without a protective interlayer. Thermodynamic and computational analyses identified Fe 3+ as a suitable dopant based on its similar reduction potential to In 3+ and structural compatibility within the halide lattice. The synthesized 10 at. % Fe-doped LIC exhibits high phase purity, retained ionic conductivity, and notably improved interfacial stability. Full-cell tests using Fe-LIC achieve over 300 cycles with 80 % capacity retention. At the same time, symmetric Li-In/ Fe-LIC/ Li-In cells sustain over 500 h of operation, representing the first reported long-term cycling of LIC-based ASSLB without a protective interlayer. In conclusion, this work establishes Fe doping as an effective strategy to stabilize halide SSEs of In system against Li-In alloy, thereby simplifying cell architecture and advancing the development of safer, high-performance halide-based solid-state electrolytes.

Halide-based solid-state electrolytes↗

Access to Ru(IV)–Ru(V) and Ru(V)–Ru(VI) Redox in Layered Li 7 RuO 6 via Intercalation Reactions

The push to increase the capacity of oxides to store charge as Li-ion battery cathodes has challenged our knowledge of the boundaries of redox chemistry and its relationship to the atomic structure. Layered phases with Ru are now classical models in the quest for refined theories. Current understanding dictates that the highest formal state that can be reached in them is Ru(V), after which activity centered at the oxide anions is triggered. Yet, this picture is challenged by this investigation of the intercalation chemistry of Li 7 RuO 6 . Coupling structural and spectroscopic analysis with computational simulations, we show that Li 7 RuO 6 is capable of highly reversible lithiation to Li 8 RuO 6 through the Ru(V)/Ru(IV) redox couple. Further, Li 7 RuO 6 can also undergo anodic Li deintercalation, showing clear evidence of the reversible formation of Ru(VI) with octahedral coordination, an unusual state that is not accessible in other layered oxides. The results highlight the versatility of the Ru-O bond to undergo distinct redox transitions depending on the specific layered arrangements. They enrich our understanding of redox chemistry in solids while underscoring the need for descriptions of charge compensation that reflect the nuance of covalent interactions.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

X-ray Nanocomputed Tomography in Zernike Phase Contrast for Studying 3D Morphology of Li–O 2 Battery Electrode

In this work, we investigated the lithium peroxide (Li 2 O 2 ) and pore size distribution in lithium-O 2 battery electrodes at different states of charge using transmission X-ray microscopy coupled with Zernike phase contrast to carry out nano-Computed Tomography. We report that such technique enables, at the nanoscale, to distinguish light elements such as carbon and Li 2 O 2 in Li-O 2 battery cathode electrodes. We verified by wave-propagation simulation that this approach efficiently improves the contrast of images in comparison with the pure absorption. The Li 2 O 2 distribution and thickness, interphases, and pore network are visualized and quantified, which give a valuable insight into our cathode architecture. From this 3D analysis, we highlight modifications of the air-cathode morphology and the Li 2 O 2 spatial organization as well as their potential implication in terms of carbon surface passivation and pore-clogging. After the full recharge process, this technique can also reveal the spatial distribution of the residual Li 2 O 2 and other byproducts.

25 ENERGY STORAGE↗