Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “solid electrolytes”

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 685 records · Page 38
All sourcesNASA NTRSDOE OSTI
DOE OSTI2026

Structural effects of composition tuning in A-site disordered perovskite La0.5Li0.5−xMxTiO3 (M = Na, K) nanorods for fast interfacial transport for solid composite electrolyte design

Polymer-ceramic composite electrolytes (CPE) have emerged as promising replacements for currently used liquid organic electrolytes, which pose as safety hazards, in Li-ion batteries. Limits in conductivity enhancement in CPEs is often attributed to a high resistance for Li-ion transport along the interface due to the incompatibility of the polymer and ceramic phases. A clear understanding of the interfacial structure and how this impacts interfacial Li-ion transport is needed in order to efficiently design a CPE with optimal ionic conductivity. In this study, density functional theory (DFT) calculations, in conjunction with scanning transmission electron microscopy (STEM) and electron energy loss spectroscopy (EELS), are used to unveil the bulk and surface structure of La0.5Li0.5−xMxTiO3 (M = Na, K) (LMTO) nanorods, a newly-reported ceramic system with promising applications in CPEs, and the LMTO interactions with the poly(lithium sulfonyl (trifluoromethane sulfonyl)imide methacrylate) (p(MTFSILi)) polymerized ionic liquid. Substitution of lithium for sodium and potassium onto the A-site perovskite lattice is shown to increase the stability of the preferred pseudocubic perovskite phase because of their increased cation size which allows them to reduce the TiO6 octahedral rotations in the bulk and at the surface. STEM and EELS results show that LMTO nanorods with differing compositions have Ti-enriched (110)-oriented surfaces. Increased sodium and potassium compositions in LMTO is also shown using the DFT calculations to weaken the binding of the lithium atom to the MTFSI unit when LiMTFSI is adsorbed to the LMTO surface. This weakening of lithium binding to the polymer at the LMTO interface indicates that the lithium mobility is increased, correlating to an increase in interfacial Li-ion transport. Overall, this work provides insights into how to tune the interfacial interactions between the polymer (p(MTFSI)) and ceramic (LMTO) for optimal CPE design.

Shepard, Lauren B [Pennsylvania State University, ↗
DOE OSTI2020

Hybrid Li-S pouch cell with a reinforced sulfide glass solid-state electrolyte film separator

Here, in this paper, sulfide glass electrolyte powder with a nominal composition of (Li 2 S) 60 (SiS 2 ) 28 (P 2 S 5 ) 12 is hot pressed at a 330°C and 12 MPa into separator films using non-woven fiberglass reinforcement. The reinforced separator films are 93% dense, bendable, and have an ionic conductivity of 0.7 mS/cm at room temperature. When integrated into hybrid Li-S coin cells with liquid electrolyte, these reinforced glass separators blocked the parasitic polysulfide shuttle sufficiently to enable reversible cycling without LiNO 3 co-salt. Furthermore, the scalability of the reinforced glass separator technology is demonstrated by assembling and testing a hybrid single-layer pouch cell.

25 ENERGY STORAGE↗
DOE OSTI2022

Use of Ethylene Carbonate Free Ester Solvent Systems with Alternative Lithium Salts for Improved Low-Temperature Performance in NCM622∣∣ Graphite Li-ion Batteries

An investigation of alternative lithium salts, lithium tetrafluoroborate (LiBF 4 ), lithium difluoro(oxalato)borate (LiDFOB) and lithium hexafluorophosphate (LiPF 6 ), in novel ester-based (methyl acetate/fluoroethylene carbonate- MA/FEC or methyl propionate/fluoroethylene carbonate- MP/FEC) electrolyte formulations has been conducted in LiNi 0.6 Co 0.2 Mn 0.2 O 2 (NCM622)/graphite cells to improve low temperature cycling performance of lithium ion batteries at −20 °C. Improved low temperature performance was observed with all the lithium salts in MA/FEC electrolyte while comparable room temperature (25 °C) capacities were observed with LiPF 6 salt only. Detailed ex-situ analysis of surface films generated with LiBF 4 , LiDFOB and LiPF 6 in ester-based electrolytes reveals that the solid electrolyte interphase (SEI) is predominately composed of lithium salt decompaction products and addition of 10% FEC (by volume%) may not be sufficient at forming a protective SEI.

25 ENERGY STORAGE↗
DOE OSTI2019

High Conductivity and Flexible Hybrid Solid State Electrolyte (Final Report: DOE-EE0007807)

The project objective is to develop flexible hybrid electrolyte with garnet nanofibers to achieve the following: (1) flexible, with greater mechanical strength (~ 10 MPa) and thermal stability than polymer electrolytes; (2) high room-temperature ionic conductivity, ~ 0.5 mS/cm; (3) stable interface with lithium metal and effective blocking of lithium dendrites at current densities up to 3 mA/cm 2 ; and (4) battery performance with Li S chemistry with an energy density of ≥ 450 Wh/kg (and ≥ 1000 Wh/L) and maintaining ≥ 80% of capacity up to 500 cycles. We synthesized garnet nanofibers, filled the porous region with polymer electrolyte, and characterized and tuned the flexible hybrid membrane properties. The flexible hybrid SSE microstructure was analyzed by leveraging the UMD AIMLab Focused Ion Beam Scanning Electron Microscopy (FIB-SEM) tools and integrated with electrochemical methods at the UMERC Battery Fabrication Lab to investigate the properties and stability with Li metal anode. We developed a fundamental understanding of the mechanism of Li ionic diffusion in garnet nanofibers and their mechanical properties, as well as these properties for hybrid garnet-fiber/polymer hybrids. Work progressed toward the study of the electrode assembly during electrochemical cycling of the anode.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Extending the operating range and safety of Li-ion batteries with new fluorinated electrolytes

Orbia Fluor and Energy Materials (formerly Koura) has successfully developed a new class of fluorinated electrolyte solvents for lithium-ion batteries. In collaboration with Silatronix and Argonne National Laboratory, the team synthesized and screened over 20 novel fluorinated compounds, optimizing formulations that significantly enhance battery performance across critical metrics such as thermal stability, fast-charging capability, and cycling life at extreme temperatures. Electrolytes with fluorinated molecules developed in this program demonstrated superior performance in 2 Ah pouch cells, achieving over 1000 fast-charge cycles with minimal capacity fade, outperforming conventional carbonate-based electrolytes. Mechanistic studies revealed that the fluorinated electrolytes promote a stable solid electrolyte interphase at the anode and reduce cathode metal dissolution, contributing to improved long-term stability. These advancements mark a significant step toward safer, more efficient batteries for applications ranging from grid storage to defense systems to electric vehicles. We gratefully acknowledge DOE’s financial support through contract DE-EE0009642.

25 ENERGY STORAGE↗
DOE OSTI2022

A Review on Gel Polymer Electrolytes for Dye-Sensitized Solar Cells

Significant growth has been observed in the research domain of dye-sensitized solar cells (DSSCs) due to the simplicity in its manufacturing, low cost, and high-energy conversion efficiency. The electrolytes in DSSCs play an important role in determining the photovoltaic performance of the DSSCs, e.g., volatile liquid electrolytes suffer from poor thermal stability. Although low volatility liquid electrolytes and solid polymer electrolytes circumvent the stability issues, gel polymer electrolytes with high ionic conductivity and enduring stability are stimulating substitutes for liquid electrolytes in DSSC. Here, in this review paper, the advantages of gel polymer electrolytes (GPEs) are discussed along with other types of electrolytes, e.g., solid polymer electrolytes and p-type semiconductor-based electrolytes. The benefits of incorporating ionic liquids into GPEs are highlighted in conjunction with the factors that affect the ionic conductivity of GPEs. The strategies on the improvement of the properties of DSSCs based on GPE are also presented.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Crossover Effects of Transition‐Metal Ions on Lithium‐Metal Anode in Localized High Concentration Electrolytes

Abstract The stability of the solid–electrolyte interphase (SEI) is critical to the cycle life of lithium‐metal batteries (LMBs). While the crossover effect of transition‐metal ions from cathode to anode is extensively studied in lithium‐ion batteries with graphite anodes, its impact on LMBs remains largely unexplored. Herein, this study investigates the electrochemical and chemical properties of SEI layers formed on lithium‐metal anodes in localized high‐concentration electrolytes (LHCEs) containing dissolved transition‐metal ions (Ni 2+ , Mn 2+ , and Co 2+ ). It is demonstrated that transition‐metal ions in LHCEs reduce the coulombic efficiency (CE) and significantly degrade the cycle life of LMBs. Time‐of‐flight secondary‐ion mass spectrometry (ToF‐SIMS) reveals that SEI structures differ depending on the dissolved TM ion, with Mn 2+ and Co 2+ inducing severe destabilization, and Ni 2+ exhibiting a less severe impact. These findings underscore the detrimental effects of transition‐metal crossover effects in LMB systems.

Guo, Zezhou [Materials Science and Engineering Pro↗