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All sourcesNASA NTRSDOE OSTI
DOE OSTI2022

Critical Barriers to Successful Implementation of Earth-Abundant, Mn-Rich Cathodes for Vehicle Applications and Beyond: The Effect of Particle Morphology

As the search for improved and next-generation cathodes continues, it is clear that a deeper understanding of synthesis–structure–electrochemical property relationships is of critical importance. The effects of primary and secondary particle morphologies on various transition metal oxides have been studied, but new findings are still being reported. To date, few studies have focused on the effects of particle morphologies on Li- and Mn-rich oxides (>50% Mn) and even fewer studies have focused on the influence over key properties such as electrode-level impedance. In this study, we report the effects of particle morphologies on the area-specific-impedance (ASI) and thermal behavior of Li- and Mn-rich oxides. Samples with a fixed, layered–layered–spinel (LLS), composition were synthesized with differing primary morphologies and tested under standardized, full-cell protocols. The results suggest that smaller primary particle size (i.e., higher surface area) leads to lower overall ASI, a delay in the increasing impedance at low states-of-charge (SOCs), and surprisingly, improved thermal behavior.

33 ADVANCED PROPULSION SYSTEMS↗
DOE OSTI2024

A Comparative Study of Degradation Behaviors of LiFePO 4 , LiMn 2 O 4 , and LiNi 0.8 Mn 0.1 Co 0.1 O 2 in Different Aqueous Electrolytes

Aqueous Li-ion batteries (ALIBs) are an important class of battery chemistries owing to the intrinsic non-flammability of aqueous electrolytes. However, water is detrimental to most cathode materials and could result in rapid cell failure. Identifying the degradation mechanisms and evaluating the pros and cons of different cathode materials are crucial to guide the materials selection and maximize their electrochemical performance in ALIBs. Here, in this study, we investigate the stability of LiFePO 4 (LFP), LiMn 2 O 4 (LMO) and LiNi 0.8 Mn 0.1 Co 0.1 O 2 (NMC) cathodes, without protective coating, in three different aqueous electrolytes, i.e., salt-in-water, water-in-salt, and molecular crowding electrolytes. The latter two are the widely reported "water-deficient electrolytes." LFP cycled in the molecular crowding electrolyte exhibits the best cycle life in both symmetric and full cells owing to the stable crystal structure. Mn dissolution and surface reduction accelerate the capacity decay of LMO in water-rich electrolyte. On the other hand, the bulk structural collapse leads to the degradation of NMC cathodes. LMO demonstrates better full-cell performance than NMC in water-deficient aqueous electrolytes. LFP is shown to be more promising than LMO and NMC for long-cycle-life ALIB full cells, especially in the molecular crowding electrolyte. However, none of the aqueous electrolytes studied here provide enough battery performance that can compete with conventional non-aqueous electrolytes. This work reveals the degradation mechanisms of olivine, spinel, and layered cathodes in different aqueous electrolytes and yields insights into improving electrode materials and electrolytes for ALIBs.

36 MATERIALS SCIENCE↗
DOE OSTI2024

Fast-Charging Li 4 Ti 5 O 12 Anode Driven by Light

Lithium-ion batteries with fast charging capabilities are crucial for widespread adoption of electric vehicles, as they will increase acceptance of the technology and reduce range anxiety for drivers. To achieve this, advanced fast charging technologies and alternative methods to enhance the slow electrochemical processes are desperately required. This study applied light-emitting diode (LED) photo-assisted fast charging to Li 4 Ti 5 O 12 (LTO), a large bandgap cubic spinel material, to enhance charging speed through electronic-structure coupling. UV LED-generated light irradiation on to the electrode interface boosted the ion diffusion and lithium cation addition by a factor of 1.3 during electrochemical lithiation, resulting in a 30% decrease in charging time under ambient conditions. Red LED light was not effective in accelerating the reaction as it does not provide sufficient energy. The first-principles calculations support the concept that UV illumination generates charges by overcoming the material’s bandgap and effectively reducing it through the introduction of additional titanium defect states.

25 ENERGY STORAGE↗
DOE OSTI2024

Unraveling the Structure and Composition of Li 4 Mn 2 O 4.5 (Li 2 O·Li 0.667 Mn 1.333 O 2 ) Electrodes for Lithium Batteries Using a High-Temperature Synthesis Approach

This paper addresses the debate about the composition and structure of a lithium-rich manganese oxide electrode with a fully disordered rock salt component, Li 4 Mn 2 O 5 (or Li 2 O·2LiMnO 2 ), first reported by Freire et al. in 2016; it is typically prepared by a high-energy ball milling procedure. It has now been demonstrated that, when prepared at 800°C, the formula of this compound is Li 4 Mn 2 O 4.5 , alternatively Li 2 O·Li 0.667 Mn 1.333 O 2 , or close thereto. The cubic, disordered Li 0.667 Mn 1.333 O 2 (or Li 0.333 Mn 0.667 O) rock salt component, in which the manganese ions adopt an average oxidation state of 2.5+, transforms to a clearly-defined spinel configuration during electrochemical cycling. The electrochemical activation process that occurs during the initial charge reaction includes the oxidation of the manganese ions by oxygen released by the Li 2 O component between 4.5 and 4.6 V. In complete contrast, nickel- and nickel-cobalt-substituted electrodes, such as Li 2 O·2LiMn 0.5 Ni 0.5 O 2 (Li 4 MnNiO 5 ) and Li 2 O·2LiMn 0.475 Ni 0.475 Co 0.050 O 2 (Li 4 Mn 0.95 Ni 0.95 Co 0.10 O 5 ), in which the manganese ions adopt a tetravalent state, have completely disordered rock salt components that are electrochemically inactive.

25 ENERGY STORAGE↗
DOE OSTI2026

A Reflection on the Evolution of Sodium/Metal Chloride (ZEBRA) Batteries and Lithium-Ion Cathode Materials (1975–2025): A Tribute to Johan Coetzer

This narrative summarizes, in retrospect, the enormous and quietly-conducted contribution of Dr Johan Coetzer, a South African scientist and entrepreneur, to the discovery, development and implementation of the high temperature sodium—metal chloride “ZEBRA” battery (Na/β-Al 2 O 3 , NaAlCl 4 /MCl 2 (M = Ni, Fe)). Here, this research activity was initiated in the mid 1970’s at the Council for Scientific and Industrial Research (CSIR) in South Africa and subsequently developed primarily in partnership with the Atomic Energy Research Establishment (AERE, Harwell, UK), Beta R&D (Derby, UK) and Daimler Benz (Germany), before being transferred to industry worldwide for electric vehicle and energy storage applications, albeit at a relatively low production rate. Coetzer’s wide-ranging, innovative and, at times, unconventional scientific approach also laid the foundation for the discovery and implementation of manganese-based spinel and layered metal oxide cathode materials for the Li-ion battery industry.

ZEBRA Battery↗
DOE OSTI2026

matsim-agents v1.0

matsim-agents is a multi-agent AI framework for atomistic materials simulation and discovery. It orchestrates large language models (LLMs), machine-learned interatomic potentials (MLIPs), and DFT codes into a single agentic loop running on laptops and DOE leadership-class supercomputers. MULTI-AGENT ORCHESTRATION A LangGraph state machine with three nodes: a Planner that converts a natural-language research objective into structured tasks; an Executor that dispatches atomistic tools and loops until the queue is empty; and an Analyst that summarizes results into a human-readable report. State is checkpointed after every step and human-in-the-loop gates can be inserted at any edge. HYPOTHESIS-DRIVEN DISCOVERY CHAT An interactive REPL (matsim-agents chat) that couples LLM dialogue with atomistic simulation. Chemical formulas are automatically detected in conversation turns and trigger a full crystal-phase exploration: structure generation → relaxation → stability scoring → result injection back into the conversation, creating a closed hypothesis-refinement loop. CRYSTAL PHASE ENUMERATION Given a composition, the phase explorer enumerates prototypes by stoichiometry: elemental (fcc/bcc/hcp/sc/diamond), binary 1:1 (rocksalt/CsCl/zincblende/ wurtzite/fluorite/rutile), ternary 1:1:3 (cubic perovskite), ternary 1:2:4 (perovskite + spinel), quaternary 1:1:2:6 (Fm-3m double perovskite). 2-D prototypes (graphene, h-BN, MoS2 2H/1T) and multilayer stacking are also supported via --include-2d and --num-layers. SUPERCELL GENERATION AND SITE DECORATION Auto-tiling to a minimum atom count (--min-atoms), explicit NxNxN tiling (--supercell), symmetry-distinct site decorations (--n-orderings), and isotropic lattice-scale sweeps (--lattice-scales) for volume bracketing. MLFF RELAXATION AND STABILITY SCORING HydraGNN (multi-headed GNN) drives structure relaxation via ASE with FIRE, BFGS, or BFGSLineSearch. Stability output: delta-E/atom ranking across phases and a max-residual-force dynamical-stability proxy. Other MLIPs (MACE, NequIP, Orb) can be plugged in through the same interface. DFT BACKENDS Quantum ESPRESSO pw.x and VASP 6.6 are first-class labellers. Both have validated GPU builds and SLURM/PBS launchers for three DOE platforms: Frontier (AMD MI250X, ROCm), Aurora (Intel PVC, oneAPI), Perlmutter (NVIDIA A100, CUDA). QE produces ~100 binaries (pw.x, ph.x, epw.x, ...). VASP supports scf, relax, vc-relax, and vc-relax-shape run types. ACTIVE-LEARNING LOOP matsim-agents al run CONFIG.yaml drives an iterative HydraGNN-DFT loop: MD generates candidates → ensemble/MC-dropout uncertainty selects the most informative → DFT labels them in parallel inside one allocation → dataset grows → HydraGNN retrains → repeat. DFT backend is a single YAML toggle (dft.backend: vasp | qe). LLM-generated seed structures are supported (no curated POSCAR library needed). Config uses ${VAR}, ${VAR:-default}, ${VAR:?msg} shell-style substitution for cross-user/cross-site portability. LLM BACKENDS Ollama (local, default), vLLM (HPC multi-GPU serving), OpenAI, Anthropic, HuggingFace Transformers+Accelerate. Selected at runtime via flag or env var with no code changes. HPC PORTABILITY Same Python entry points run on Frontier (ROCm 7.2), Aurora (oneAPI), and Perlmutter (CUDA 12). DFT and ML stacks are never co-loaded in the same shell; they couple through the scheduler and filesystem. Advanced multi-node launchers (serve, discovery-chat, single-relaxation, active-learning, QE warm-start) are provided for all three platforms. CODABENCH COMPETITION BUNDLE A self-contained benchmark: 159 atomistic test structures across 11 material classes, 5 tasks (formation energy, forces, ML relaxation, AI-DFT relaxation, phase stability ranking), public/private leaderboard split (30/70), and four ready-to-run baselines: MACE-MP-0, HydraGNN, UMA, AllScAIP.

Lupo Pasini, Massimiliano [Oak Ridge National Labo↗
DOE OSTI2023

LTE-P-14 Non PGM Conductivity measurement

A procedure for measuring the electrical conductivity of PGM-free OER catalyst powders to allow comparison of one material to another. This standard two-point conductivity protocol is applicable to transition metal oxides, mixed oxides, perovskites, spinels, etc.

08 HYDROGEN↗
DOE OSTI2020

Materials Data on P2Ir by Materials Project

IrP2 is Spinel-derived structured and crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Ir4+ is bonded to six P2- atoms to form IrP6 octahedra that share corners with eight equivalent IrP6 octahedra, corners with six PPIr3 tetrahedra, and edges with two equivalent IrP6 octahedra. The corner-sharing octahedra tilt angles range from 56–62°. There are a spread of Ir–P bond distances ranging from 2.34–2.43 Å. There are two inequivalent P2- sites. In the first P2- site, P2- is bonded to three equivalent Ir4+ and one P2- atom to form PPIr3 tetrahedra that share corners with three equivalent IrP6 octahedra, corners with thirteen PPIr3 tetrahedra, and an edgeedge with one PPIr3 tetrahedra. The corner-sharing octahedra tilt angles range from 67–71°. The P–P bond length is 2.24 Å. In the second P2- site, P2- is bonded to three equivalent Ir4+ and one P2- atom to form PPIr3 tetrahedra that share corners with three equivalent IrP6 octahedra, corners with thirteen PPIr3 tetrahedra, and an edgeedge with one PPIr3 tetrahedra. The corner-sharing octahedra tilt angles range from 72–78°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Lu2MgSe4 by Materials Project

MgLu2Se4 is Spinel structured and crystallizes in the cubic Fd-3m space group. The structure is three-dimensional. Mg2+ is bonded to four equivalent Se2- atoms to form MgSe4 tetrahedra that share corners with twelve equivalent LuSe6 octahedra. The corner-sharing octahedral tilt angles are 57°. All Mg–Se bond lengths are 2.61 Å. Lu3+ is bonded to six equivalent Se2- atoms to form LuSe6 octahedra that share corners with six equivalent MgSe4 tetrahedra and edges with six equivalent LuSe6 octahedra. All Lu–Se bond lengths are 2.82 Å. Se2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three equivalent Lu3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CoPSe by Materials Project

CoPSe is Spinel-like structured and crystallizes in the orthorhombic Pbca space group. The structure is three-dimensional. Co3+ is bonded to three equivalent P1- and three equivalent Se2- atoms to form CoP3Se3 octahedra that share corners with ten equivalent CoP3Se3 octahedra, corners with three equivalent PCo3Se tetrahedra, corners with three equivalent SeCo3P tetrahedra, and an edgeedge with one CoP3Se3 octahedra. The corner-sharing octahedra tilt angles range from 55–66°. There are a spread of Co–P bond distances ranging from 2.22–2.25 Å. There are a spread of Co–Se bond distances ranging from 2.39–2.44 Å. P1- is bonded to three equivalent Co3+ and one Se2- atom to form PCo3Se tetrahedra that share corners with three equivalent CoP3Se3 octahedra, corners with four equivalent PCo3Se tetrahedra, corners with nine equivalent SeCo3P tetrahedra, and an edgeedge with one PCo3Se tetrahedra. The corner-sharing octahedra tilt angles range from 76–78°. The P–Se bond length is 2.36 Å. Se2- is bonded to three equivalent Co3+ and one P1- atom to form SeCo3P tetrahedra that share corners with three equivalent CoP3Se3 octahedra, corners with six equivalent SeCo3P tetrahedra, and corners with nine equivalent PCo3Se tetrahedra. The corner-sharing octahedra tilt angles range from 73–81°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Fe(RhS2)2 by Materials Project

FeRh2S4 is Spinel structured and crystallizes in the cubic Fd-3m space group. The structure is three-dimensional. Fe2+ is bonded to four equivalent S2- atoms to form FeS4 tetrahedra that share corners with twelve equivalent RhS6 octahedra. The corner-sharing octahedral tilt angles are 58°. All Fe–S bond lengths are 2.30 Å. Rh3+ is bonded to six equivalent S2- atoms to form RhS6 octahedra that share corners with six equivalent FeS4 tetrahedra and edges with six equivalent RhS6 octahedra. All Rh–S bond lengths are 2.39 Å. S2- is bonded to one Fe2+ and three equivalent Rh3+ atoms to form a mixture of distorted edge and corner-sharing SFeRh3 trigonal pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NiAsSe by Materials Project

NiAsSe is Spinel-like structured and crystallizes in the cubic P2_13 space group. The structure is three-dimensional. Ni3+ is bonded to three equivalent As1- and three equivalent Se2- atoms to form NiAs3Se3 octahedra that share corners with twelve equivalent NiAs3Se3 octahedra, corners with three equivalent SeNi3As tetrahedra, and corners with three equivalent AsNi3Se trigonal pyramids. The corner-sharing octahedra tilt angles range from 63–64°. All Ni–As bond lengths are 2.42 Å. All Ni–Se bond lengths are 2.46 Å. As1- is bonded to three equivalent Ni3+ and one Se2- atom to form AsNi3Se trigonal pyramids that share corners with three equivalent NiAs3Se3 octahedra, corners with nine equivalent SeNi3As tetrahedra, and corners with six equivalent AsNi3Se trigonal pyramids. The corner-sharing octahedral tilt angles are 79°. The As–Se bond length is 2.49 Å. Se2- is bonded to three equivalent Ni3+ and one As1- atom to form SeNi3As tetrahedra that share corners with three equivalent NiAs3Se3 octahedra, corners with six equivalent SeNi3As tetrahedra, and corners with nine equivalent AsNi3Se trigonal pyramids. The corner-sharing octahedral tilt angles are 80°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on SbTePd by Materials Project

PdSbTe is Spinel-like structured and crystallizes in the cubic P2_13 space group. The structure is three-dimensional. Pd4+ is bonded to three equivalent Sb2- and three equivalent Te2- atoms to form PdSb3Te3 octahedra that share corners with twelve equivalent PdSb3Te3 octahedra, corners with three equivalent SbTePd3 trigonal pyramids, and corners with three equivalent TeSbPd3 trigonal pyramids. The corner-sharing octahedral tilt angles are 63°. All Pd–Sb bond lengths are 2.73 Å. All Pd–Te bond lengths are 2.78 Å. Sb2- is bonded to three equivalent Pd4+ and one Te2- atom to form SbTePd3 trigonal pyramids that share corners with three equivalent PdSb3Te3 octahedra, corners with six equivalent SbTePd3 trigonal pyramids, and corners with nine equivalent TeSbPd3 trigonal pyramids. The corner-sharing octahedral tilt angles are 80°. The Sb–Te bond length is 2.91 Å. Te2- is bonded to three equivalent Pd4+ and one Sb2- atom to form TeSbPd3 trigonal pyramids that share corners with three equivalent PdSb3Te3 octahedra, corners with six equivalent TeSbPd3 trigonal pyramids, and corners with nine equivalent SbTePd3 trigonal pyramids. The corner-sharing octahedral tilt angles are 81°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sc2CdS4 by Materials Project

CdSc2S4 is Spinel structured and crystallizes in the cubic Fd-3m space group. The structure is three-dimensional. Sc3+ is bonded to six equivalent S2- atoms to form ScS6 octahedra that share corners with six equivalent CdS4 tetrahedra and edges with six equivalent ScS6 octahedra. All Sc–S bond lengths are 2.60 Å. Cd2+ is bonded to four equivalent S2- atoms to form CdS4 tetrahedra that share corners with twelve equivalent ScS6 octahedra. The corner-sharing octahedral tilt angles are 58°. All Cd–S bond lengths are 2.55 Å. S2- is bonded to three equivalent Sc3+ and one Cd2+ atom to form a mixture of distorted corner and edge-sharing SSc3Cd trigonal pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Li2TeO4 by Materials Project

Li2TeO4 is Spinel-like structured and crystallizes in the tetragonal P4_122 space group. The structure is three-dimensional. there are two inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with six equivalent LiO6 octahedra and corners with six equivalent TeO6 octahedra. The corner-sharing octahedra tilt angles range from 51–66°. There are two shorter (1.99 Å) and two longer (2.06 Å) Li–O bond lengths. In the second Li1+ site, Li1+ is bonded to six O2- atoms to form distorted LiO6 octahedra that share corners with six equivalent LiO4 tetrahedra, edges with two equivalent LiO6 octahedra, and edges with four equivalent TeO6 octahedra. There are a spread of Li–O bond distances ranging from 1.98–2.36 Å. Te6+ is bonded to six O2- atoms to form TeO6 octahedra that share corners with six equivalent LiO4 tetrahedra, edges with two equivalent TeO6 octahedra, and edges with four equivalent LiO6 octahedra. There are a spread of Te–O bond distances ranging from 1.87–2.07 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded to two Li1+ and two equivalent Te6+ atoms to form distorted OLi2Te2 trigonal pyramids that share corners with six equivalent OLi3Te tetrahedra, corners with six equivalent OLi2Te2 trigonal pyramids, edges with two equivalent OLi3Te tetrahedra, and an edgeedge with one OLi2Te2 trigonal pyramid. In the second O2- site, O2- is bonded to three Li1+ and one Te6+ atom to form distorted OLi3Te tetrahedra that share corners with six equivalent OLi3Te tetrahedra, corners with six equivalent OLi2Te2 trigonal pyramids, an edgeedge with one OLi3Te tetrahedra, and edges with two equivalent OLi2Te2 trigonal pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Zr2CuS4 by Materials Project

CuZr2S4 is Spinel structured and crystallizes in the cubic Fd-3m space group. The structure is three-dimensional. Zr+3.50+ is bonded to six equivalent S2- atoms to form ZrS6 octahedra that share corners with six equivalent CuS4 tetrahedra and edges with six equivalent ZrS6 octahedra. All Zr–S bond lengths are 2.60 Å. Cu1+ is bonded to four equivalent S2- atoms to form CuS4 tetrahedra that share corners with twelve equivalent ZrS6 octahedra. The corner-sharing octahedral tilt angles are 55°. All Cu–S bond lengths are 2.29 Å. S2- is bonded in a rectangular see-saw-like geometry to three equivalent Zr+3.50+ and one Cu1+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Lu2MgS4 by Materials Project

MgLu2S4 is Spinel structured and crystallizes in the cubic Fd-3m space group. The structure is three-dimensional. Mg2+ is bonded to four equivalent S2- atoms to form MgS4 tetrahedra that share corners with twelve equivalent LuS6 octahedra. The corner-sharing octahedral tilt angles are 57°. All Mg–S bond lengths are 2.49 Å. Lu3+ is bonded to six equivalent S2- atoms to form LuS6 octahedra that share corners with six equivalent MgS4 tetrahedra and edges with six equivalent LuS6 octahedra. All Lu–S bond lengths are 2.68 Å. S2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three equivalent Lu3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Lu2MnS4 by Materials Project

MnLu2S4 is Spinel structured and crystallizes in the cubic Fd-3m space group. The structure is three-dimensional. Lu3+ is bonded to six equivalent S2- atoms to form LuS6 octahedra that share corners with six equivalent MnS4 tetrahedra and edges with six equivalent LuS6 octahedra. All Lu–S bond lengths are 2.68 Å. Mn2+ is bonded to four equivalent S2- atoms to form MnS4 tetrahedra that share corners with twelve equivalent LuS6 octahedra. The corner-sharing octahedral tilt angles are 56°. All Mn–S bond lengths are 2.44 Å. S2- is bonded in a distorted rectangular see-saw-like geometry to three equivalent Lu3+ and one Mn2+ atom.

36 MATERIALS SCIENCE↗