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Accelerating computational materials discovery with artificial intelligence and cloud high-performance computing: from large-scale screening to experimental validation

Chi Chen, Dan Thien Nguyen, Shannon J. Lee, Nathan A. Baker, Ajay S. Karakoti, Linda Lauw, Craig Owen, Karl T. Mueller, Brian A. Bilodeau, Vijayakumar Murugesan, Matthias Troyer

arXiv:2401.04070v1cond-mat.mtrl-sciphysics.comp-ph

TL;DR

Large-scale computational discovery still faces resource constraints, and examples that carry candidate materials through experimental validation of functional properties remain scarce. This study combines AI models and cloud HPC to screen solid-state-electrolyte candidates and experimentally validate selected compositions. The workflow produced broad screening datasets and validated Na/Li-containing compounds with conductivities that make them candidates for future solid-electrolyte development.

  • Problem

    Large-scale computational materials discovery is constrained by computing resources, while large hypothetical-material datasets and experimental demonstrations of functional properties remain limited.

    Source: §1 · pp. 2–3
  • Method

    The study combines AI models and cloud HPC to filter candidate solid-state electrolytes, then experimentally validates selected compositions and properties.

    Source: §1 · p. 3, §2.5 · p. 8, §3 · p. 11
  • Results

    In less than 80 hours on approximately 1,000 VMs, the workflow produced ESW data for 8,795 materials and diffusivity data for 583, while Na/Li substitutional compounds showed conductivities making them viable solid-electrolyte candidates.

    Source: §2.4 · p. 7, §3 · p. 11
  • Takeaways & Limitations

    The Na/Li-substitutional halide framework could support versatile battery designs through its ability to host both Na and Li ions efficiently.

    Source: §3 · p. 11

    The stringent ESW filters excluded many known electrolytes, including sulfides such as Li10GePS12 and oxides such as Li7La3Zr2O12.

    Source: §3 · p. 11

Abstract

from arXiv · show

High-throughput computational materials discovery has promised significant acceleration of the design and discovery of new materials for many years. Despite a surge in interest and activity, the constraints imposed by large-scale computational resources present a significant bottleneck. Furthermore, examples of large-scale computational discovery carried through experimental validation remain scarce, especially for materials with product applicability. Here we demonstrate how this vision became reality by first combining state-of-the-art artificial intelligence (AI) models and traditional physics-based models on cloud high-performance computing (HPC) resources to quickly navigate through more than 32 million candidates and predict around half a million potentially stable materials. By focusing on solid-state electrolytes for battery applications, our discovery pipeline further identified 18 promising candidates with new compositions and rediscovered a decade's worth of collective knowledge in the field as a byproduct. By employing around one thousand virtual machines (VMs) in the cloud, this process took less than 80 hours. We then synthesized and experimentally characterized the structures and conductivities of our top candidates, the Na$_x$Li$_{3-x}$YCl$_6$ ($0 < x < 3$) series, demonstrating the potential of these compounds to serve as solid electrolytes. Additional candidate materials that are currently under experimental investigation could offer more examples of the computational discovery of new phases of Li- and Na-conducting solid electrolytes. We believe that this unprecedented approach of synergistically integrating AI models and cloud HPC not only accelerates materials discovery but also showcases the potency of AI-guided experimentation in unlocking transformative scientific breakthroughs with real-world applications.

1 Introduction

AI and curated materials data have expanded computational exploration, but large-scale resources and experimental validation of functional materials remain challenges. This work combines AI and cloud HPC to discover and experimentally validate candidate solid-state electrolytes.

1 Introduction

  • AI models can predict quantum-mechanical results far faster and optimize structures, enabling exploration of chemical spaces larger than the set of known materials.The paper describes models as several orders of magnitude faster than direct simulation.Source: §1 · p. 2
  • Recent studies generated large datasets of hypothetical materials without experimental validation, while technical validation of functional properties remained to be demonstrated.The paper notes that discovering technologically relevant materials is harder than finding synthesizable ones because they can be property outliers.Source: §1 · pp. 2–3
  • Evaluating even readily generated candidate pools requires substantial computing resources, slowing progress despite faster ML-based potentials.Cloud HPC is presented as a way to evaluate more small-scale, complex calculation jobs and lower entry barriers through reproducible workflows.Source: §1 · p. 3
  • The study combines AI and cloud HPC to identify and experimentally validate new solid-state-electrolyte compositions with targeted properties.The authors describe the process as rapidly identifying candidates and reducing time from concept to solution.Source: §1 · p. 3

2 Large-scale materials discovery

The study uses broad ionic substitution of known crystal structures to search a large chemical space for candidate materials. The resulting candidates span many elements, space groups, and crystal systems.

2.1 Exploring a vast chemical space

  • The search starts from 54 selected elements and deliberately avoids constraints based on ionic similarity, broadening the substitution space.Later-row transition metals, most lanthanides, noble gases, and actinides were excluded based on their stated relevance to battery materials or functional applications.Source: §2.1 · p. 3
  • Ionic substitution generated 32,598,079 initial candidates from ordered ICSD structures using common oxidation states and structure prototypes.The approach used Pymatgen StructureMatcher and iso-valent substitutions.Source: §2.1 · p. 3
  • The candidates cover 184 of 230 space groups and all seven crystal systems, expanding beyond matterverse.ai in prototype count, atom limit, and anion scope.Figure 1 presents element and space-group distributions for the initial candidates.Source: §2.1 · p. 4, Figure 1 · p. 4
  • The broad substitution strategy is less thorough for any single composition than structure-prediction approaches such as AIRSS, USPEX, and CALYPSO, but is intended to sample material space more diversely.The authors say it has a less-biased focus on specific regions of material space.Source: §2.1 · p. 4
  • The screening workflow concluded with 23 candidates, 18 of which had compositions not previously reported.Figure 2 depicts the main stages used to filter candidate materials.Source: Figure 2 · p. 5

2.2 Screening workflow for stable materials and solid electrolytes

The workflow narrows candidate materials through fast AI filters followed by higher-accuracy physics-based calculations and practical battery-property filters. Cloud infrastructure supports the large computational workload.

2.2 Screening workflow for stable materials and solid electrolytes

  • The two-stage workflow reduced 32.6 million candidates to 589,609 predicted stable materials, then applied electronic, electrochemical, and diffusivity filters to identify promising solid electrolytes.The first stage used ML potentials for relaxation and phase stability; later filters included band gap, redox potentials, and Li diffusivity.Source: §2.2 · pp. 5–6
  • Practicality filters removed selected costly elements, materials with bulk or shear moduli above 30 GPa, and densities above 2.5 g cm−3, leaving 23 finalists, including 18 with previously unreported compositions.The workflow also evaluated ordered structures derived from partially substituted disordered Na-Li phases and kept the lowest-energy structures.Source: §2.2 · p. 6

2.3 Infrastructure for cloud-based materials discovery

  • The cloud setup ran containerized ML and DFT jobs through SLURM on adjustable VM scale sets, with each job isolated in its own container.The VM scale set serves as the counterpart of a conventional HPC partition or queue.Source: §2.3 · p. 6, Figure 3 · p. 7
  • A searchable CosmosDB database tracked job and chunk status to support restarts on pre-emptible or low-priority VMs; the study used approximately 1,000 VMs.The cloud environment supported tasks from Python scripting to DFT and molecular-dynamics calculations.Source: §2.3 · p. 6

2.4 Screening results and trends

The screening produced large electrochemical-stability and diffusivity datasets, with trends that distinguish anion families. Halides, particularly bromides and chlorides, emerge as promising electrolyte families in the reported analyses.

2.4 Screening results and trends

  • Approximately 1,000 VMs running for less than 80 hours produced ESW data for 8,795 materials and diffusivity data for 583 compositions and structures.The authors state that these datasets can guide future electrolyte design.Source: §2.4 · p. 7
  • Early-row halides F, Cl, and Br tend to have larger electrochemical stability windows, oxides follow closely, and S- and Se-based chalcogenides have very small windows.The reported trend matched a previous study of Li-M-X ternary systems.Source: §2.4 · p. 8
  • The 583 candidates passing ESW filters contained Br, Cl, F, or O; bromides and chlorides showed consistently good high-temperature Li diffusivities, while oxide and fluoride diffusivities varied widely.The authors associate the oxide and fluoride variation with sensitivity of conductivity to structural changes, citing the tetragonal and cubic phases of Li7La3Zr2O12.Source: §2.4 · p. 8

2.5 Final candidates

The study selected four rare-earth halides for experimental investigation, including three candidates that passed every property filter and a predicted Li3YCl6 polymorph. Na2LiYCl6 was especially notable for its potential Li–Na dual conductivity.

2.5 Final candidates

  • Four rare-earth halides were selected for experimental validation: Li5YCl8, Li7Y2Cl13, Na2LiYCl6, and a Pna21 polymorph of Li3YCl6.The first three passed all property filters; the Li3YCl6 polymorph passed property-based filters.Source: §2.5 · p. 8
  • Na2LiYCl6 was of particular interest because it showed Li–Na dual-conductivity properties.The study identifies a framework accommodating two distinct alkali cations as a potential route to broaden solid-electrolyte formulations.Source: §2.5 · pp. 8–9
  • The selected halides had good DFT electrochemical stability windows, large DFT band gaps, and good predicted room-temperature Li conductivities from ab initio molecular dynamics.Na2LiYCl6 was singled out for its Li–Na dual-conductivity properties.Source: §2.5 · p. 8

2.6 Synthesis and experimental characterization

The synthesized Na_xLi_3−xYCl_6 series showed composition-dependent phases and increasing conductivity with Li substitution. Na2LiYCl6 had substantially higher measured conductivity and lower activation energy than parent Na3YCl6, although structural characterization remains preliminary.

2.6.1 Structure and composition

  • PXRD showed the Na3YCl6 R-3 phase as the main phase for x = 1.5 to 3, while x = 0 to 0.5 matched trigonal Li3YCl6 P-3m1.Syntheses targeting Li3YCl6, Li5YCl8, and Li7Y2Cl13 yielded Li3YCl6 in its known P-3m1 phase; Na2LiYCl6 PXRD matched the predicted Na3YCl6 R-3 structure.Source: §2.6.1 · p. 9
  • PXRD characterization was limited by humidity-affected crystallinity, Kapton-tape background, and broadened peaks that impeded accurate unit-cell refinement.Preliminary single-crystal XRD suggested successful synthesis of Na2LiYCl6 R-3; additional measurements were ongoing to confirm all series compositions.Source: §2.6.1 · p. 10
  • XPS showed qualitative agreement between measured Li/Na ratios and nominal compositions, while SEM and EDS confirmed relative Na, Y, and Cl ratios in bulk samples.Source: §2.6.1 · p. 10

2.6.2 Conductivity

  • At 100 °C, Na2LiYCl6 reached 2.2 × 10^-6 S/cm versus 6.0 × 10^-8 S/cm for Na3YCl6, while Li substitution lowered activation energy relative to the parent.Measured conductivity rose with increasing Li content; activation energies were 0.46–0.66 eV for x = 0.5 to 3 versus 0.82 eV for Na3YCl6.Source: Figure 5 · p. 9, §2.6.2 · p. 10
  • The authors suggest enhanced conductivity and reduced activation energy in Li-substituted NaxLi3−xYCl6 may reflect Li+ transport and possible expanded diffusion channels or local disorder, pending validation of Na/Li pathways.Source: §2.6.2 · p. 10

3 Discussion

The discussion frames the workflow as a way to narrow a vast candidate pool to materials with application-relevant properties and experimentally validated electrolyte compositions. It also identifies stringent filters and an ordered-crystal training scope as boundaries on what the search can capture.

Functional discovery

  • With state-of-the-art AI and cloud HPC, researchers predicted half a million stable, potentially synthesizable materials from over 32 million candidates; filters found only a small number suited to targeted applications.Source: §3 · p. 11

Designing solid-state electrolytes

  • The study predicted new Na- and Li-containing electrolyte compositions and experimentally validated NaxLi3−xYCl6-based compounds with conductivities considered viable for future electrolyte development.The workflow also recovered a decade of electrochemical stability-window trends, with halides showing the most promising balance of stability window and conductivity.Source: §3 · p. 11

Next steps

  • The stringent electrochemical-stability-window filter excluded many candidates, including known sulfide Li10GePS12 and oxide Li7La3Zr2O12 electrolytes.Relaxing the filter may reveal additional electrolyte candidates among the 8,795 compounds that entered that filter.Source: §3 · p. 11
  • The ML training set used only integer atomic occupancies, leaving disordered site occupancies and defects—common in fast Li conductors—outside the screened materials space.The authors call for extending the search beyond ordered, perfect crystals.Source: §3 · p. 12

Broader impact

  • The integrated AI and cloud-HPC workflow is presented as an end-to-end approach with potential to accelerate identification, synthesis, and experimental validation of technologically relevant materials.Source: §3 · p. 12

4 Methods

The methods combine trained M3GNet potentials and DFT/AIMD screening with synthesis and multiple characterization methods to evaluate Na_xLi_3−xYCl_6 electrolytes.

4.1 AI model, training, and data

  • The M3GNet potential was trained on curated Materials Project structures, with test errors of 29.9 meV/atom, 72.1 meV/Å, and 0.40 GPa.The dataset comprised 352,767 structures split into 317,489 training, 17,633 validation, and 17,645 test snapshots.Source: §4.1 · p. 12

4.2 DFT

  • DFT and AIMD used VASP; trajectories covered at least 80 atoms, 200 ps, and 400–700 K, with Na2LiYCl6 simulated at 700–1000 K.The materials did not melt during the simulations.Source: §4.2 · pp. 12–13

4.3 Synthesis methods

  • Stoichiometric NaCl, LiCl, and YCl3 mixtures were ground, pelletized, sealed in evacuated quartz ampoules, and annealed for five hours at 450–550 °C.Reagents and samples were handled in an Ar glovebox to minimize water contamination.Source: §4.3 · p. 13

4.4.1 XRD

  • PXRD samples were covered with Kapton tape during measurement to limit moisture degradation.Measurements used a Rigaku SmartLab SE diffractometer with a Cu source.Source: §4.4.1 · p. 13

4.4.2 XPS

  • Air-free XPS measurements used Li 1s, Na 2s, Y 3d, and Cl 2p spectra to calculate sample composition.Spectra were calibrated to the C 1s signal at 285 eV.Source: §4.4.2 · pp. 13–14

4.4.3 SEM and EDS

  • SEM/EDS measured relative Na, Y, and Cl ratios at at least 10 sites per composition; Li was not detectable by EDS.Oxygen was observed at sample surfaces despite quick transfer from the glovebox.Source: §4.4.3 · p. 14

4.4.4 Electrochemical impedance spectra (EIS) measurement

  • Ionic conductivity was determined from impedance measurements of pelletized electrolyte between stainless-steel electrodes across 25–100 °C.Cells were pressurized to 250 MPa, and rested for two hours at each temperature before measurement.Source: §4.4.4 · p. 14

Competing interests

Several authors work at Microsoft, and two provisional patents were filed.

Appendix A Acronyms

The appendix expands commonly used abbreviations for methods, materials, and computing terms.

  • AI means artificial intelligence, while DFT and PBE mean density functional theory and Perdew–Burke–Ernzerhof, respectively.Source: Appendix A · p. 20
  • AIMD denotes ab initio molecular dynamics, and EIS and ESW denote electrochemical impedance spectra and electrochemical stability window.Source: Appendix A · p. 20
  • HPC, GPU, and ICSD denote high-performance computing, graphics processing unit, and Inorganic Crystal Structure Database.Source: Appendix A · p. 20
  • PXRD, SEM, XPS, and EDS expand to powder X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy, and energy-dispersive X-ray spectroscopy.Source: Appendix A · p. 20

Appendix B Supplementary information

Supplementary figures and tables document candidate properties and characterization of the Na_xLi_3−xYCl_6 series.

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