| 1. |
- Agostini, Marco, 1987, et al.
(author)
-
Designing a Safe Electrolyte Enabling Long‐Life Li/S Batteries
- 2019
-
In: ChemSusChem. - : Wiley. - 1864-5631 .- 1864-564X. ; 12:18, s. 4176-4184
-
Journal article (peer-reviewed)abstract
- Lithium–sulfur (Li/S) batteries suffer from “shuttle” reactions in which soluble polysulfide species continuously migrate to and from the Li metal anode. As a consequence, the loss of active material and reactions at the surface of Li limit the practical applications of Li/S batteries. LiNO3 has been proposed as an electrolyte additive to reduce the shuttle reactions by aiding the formation of a stable solid electrolyte interphase (SEI) at the Li metal, limiting polysulfide shuttling. However, LiNO3 is continuously consumed during cycling, especially at low current rates. Therefore, the Li/S battery cycle life is limited by the LiNO3 concentration in the electrolyte. In this work, an ionic liquid (IL) [N-methyl-(n-butyl)pyrrolidinium bis(trifluoromethylsulfonyl)imide] was used as an additive to enable longer cycle life of Li/S batteries. By tuning the IL concentration, an enhanced stability of the SEI and lower flammability of the solutions were demonstrated, that is, higher safety of the battery. The Li/S cell built with a high sulfur mass loading (4 mg cm−2) and containing the IL-based electrolyte demonstrated a stable capacity of 600 mAh g−1 for more than double the number of cycles of a cell containing LiNO3 additive.
|
|
| 2. |
- Agostini, M., et al.
(author)
-
Polysulfide-containing Glyme-based Electrolytes for Lithium Sulfur Battery
- 2015
-
In: Chemistry of Materials. - : American Chemical Society (ACS). - 1520-5002 .- 0897-4756. ; 27:13, s. 4604-4611
-
Journal article (peer-reviewed)abstract
- A new comparative investigation of lithium sulfur cells employing a tetraethylene glycol dimethyl ether-lithium trifluoromethanesulfonate (TEGDME-LiCF3SO3) electrolyte charged by various polysulfide species (Li2S2, Li2S4, Li2S6, and Li2S8) is here reported. We carefully detect the effects of lithium polysulfide addition by originally combining X-ray photoelectron spectroscopy (XPS) and electrochemical impedance spectroscopy (EIS). The measurements clearly reveal how the polysulfide addition affects the nature and composition of the solid electrolyte interphase (SEI) in terms of precipitated S-based species determined by XPS. The study demonstrates that the SEI layer formed on the Li anode decreases in impedance and stabilizes by the presence of polysulfide. This, together with a buffer effect strongly mitigating the sulfur-cathode dissolution and the shuttle reaction, significantly improves the stability of the lithium-sulfur cell. The data here reported clearly suggest the polysulfide as an effective additive to enhance the performance of the lithium-sulfur battery (Graph Presented).
|
|
| 3. |
- Aguilera Medina, Luis, 1983, et al.
(author)
-
A structural study of LiTFSI-tetraglyme mixtures: From diluted solutions to solvated ionic liquids
- 2015
-
In: Journal of Molecular Liquids. - : Elsevier BV. - 0167-7322. ; 210:Part B, s. 238-242
-
Journal article (peer-reviewed)abstract
- We report on the nano-structure of solvated ionic liquids (SILs) formed by dissolving a Li-salt (LiTFSI) in the solvent tetraglyme. Using small angle X-ray scattering (SAXS), supported by Raman spectroscopy and computational modeling we follow how the nano-structure develops as Li-salt is added to the solvent. We find that, as the Li-salt concentration is increased a peak at Q 0.95 Å- 1 grows in intensity, signaling the presence of structural correlations typical of those found in traditional ionic liquids. The intensity of the peak reaches its maximum at the equimolar concentration, where each Li-ion can be solvated by one solvent molecule forming an effective cation complex. Combining the SAXS data with computer modeling we show that this peak can be assigned to charge alternation, also found in traditional ionic liquids. However, we also show that even at the equimolar concentration not all Li-ions are solvated by the solvent molecules, but a small fraction interacts directly with the anion (TFSI).
|
|
| 4. |
- Brige, Amandine, et al.
(author)
-
A comparative study of hydroxyethylcellulose-based solid polymer electrolytes for solid state Zn batteries
- 2023
-
In: NANO SELECT. - : Wiley. - 2688-4011. ; 4:1, s. 102-111
-
Journal article (peer-reviewed)abstract
- Rechargeable zinc metal batteries are greener and safer alternative to lithium batteries, but they suffer from poor reversibility due to growth of zinc dendrites and water splitting reactions of aqueous electrolytes. One strategy to overcome these drawbacks is replacing aqueous electrolyte with solid polymer electrolyte (SPE). In this work, we examine the possibility of fabricating solid electrolyte from a bio-based polymer, hydroxyethylcellulose (HEC), with the aim to further increase the sustainability of zinc batteries. Various types of zinc salts, drying procedures and the salt concentrations are investigated for their impact on the ionic conductivity, structure, and phase behavior of as-prepared polymer electrolytes. It is found that HEC has a good film-forming ability compared with commonly used poly(ethylene oxide) but its low salt-dissociation capability leads to an ionic conductivity of 10(-6) S cm(-1) even at the elevated temperature of 110 degrees C, hindering the possibility of solely utilizing HEC as matrix of solid electrolyte. Our results suggest that introducing a new polymer with higher salt-dissociation capability or lower glass transition temperature into the HEC matrix can be a reliable way to build solid polymer electrolytes with sufficient ionic conductivity and good mechanical property for future zinc batteries.
|
|
| 5. |
- Calcagno, Giulio, 1990, et al.
(author)
-
Effect of Nitrogen Doping on the Performance of Mesoporous CMK-8 Carbon Anodes for Li-Ion Batteries
- 2020
-
In: Energies. - : MDPI AG. - 1996-1073 .- 1996-1073. ; 13:19
-
Journal article (peer-reviewed)abstract
- Designing carbonaceous materials with heightened attention to the structural properties such as porosity, and to the functionalization of the surface, is a growing topic in the lithium-ion batteries (LIBs) field. Using a mesoporous silica KIT-6 hard template, mesoporous carbons belonging to the OMCs (ordered mesoporous carbons) family, namely 3D cubic CMK-8 and N-CMK-8 were synthesized and thoroughly structurally characterized. XPS analysis confirmed the successful introduction of nitrogen, highlighting the nature of the different nitrogen atoms incorporated in the structure. The work aims at evaluating the electrochemical performance of N-doped ordered mesoporous carbons as an anode in LIBs, underlining the effect of the nitrogen functionalization. The N-CMK-8 electrode reveals higher reversible capacity, better cycling stability, and rate capability, as compared to the CMK-8 electrode. Coupling the 3D channel network with the functional N-doping increased the reversible capacity to similar to 1000 mAh center dot g(-1) for the N-CMK-8 from similar to 450 mAh center dot g(-1) for the undoped CMK-8 electrode. A full Li-ion cell was built using N-CMK-8 as an anode, commercial LiFePO4, a cathode, and LP30 commercial electrolyte, showing stable performance for 100 cycles. The combination of nitrogen functionalization and ordered porosity is promising for the development of high performing functional anodes.
|
|
| 6. |
- Jiao, Xingxing, et al.
(author)
-
Morphology evolution of electrodeposited lithium on metal substrates
- 2023
-
In: Energy Storage Materials. - 2405-8297. ; 61
-
Journal article (peer-reviewed)abstract
- Lithium (Li) metal is deemed to be the high-energy-density anode material for next generation batteries, but its practical application is impeded by the uneven electrodeposition during charge of battery, which leads to the low Coulombic efficiency and potential safety issue. Here, multiscale modeling is fabricated to understand the morphology evolution of Li during electrodeposition process, from the self-diffusion of Li adatoms on electrode surface, to the nucleation process, and to the formation of Li microstructures, revealing the correlation between final morphology and deposition substrates. Energy batteries and self-diffusion of Li adatom on various substrates (lithium, copper, nickel, magnesium, and silver) result in the different nucleation size, which is calculated by kinetic Monte Carlo simulation based on classical nucleation theory. Formation of Li substructures that are grown from Li nuclei, is revealed by phase field modeling coupled with cellular automaton method. Our results show that larger Li nuclei is obtained under faster self-diffusion of Li adatom, leading to the low aspect ratio of Li substructures and the subsequent morphology evolution of electrodeposited Li. Furthermore, the electrodeposition of Li is strongly regulated by the selection of substrates, giving the practical guideline of anode design in rechargeable Li metal batteries. It is worthy to mention that this method to investigate the electro-crystallization process involving nucleation and growth can be transplanted to the other metallic anode, such as sodium, potassium, zinc, magnesium, calcium and the like.
|
|
| 7. |
- Klein, Antoine, 1998, et al.
(author)
-
Identifying the Role of Electrolyte Additives for Lithium Plating on Graphite Electrode by Operando X-ray Tomography
- 2024
-
In: Batteries and Supercaps. - 2566-6223. ; 49:12, s. 5060-5083
-
Journal article (peer-reviewed)abstract
- The plating of lithium metal on the graphite electrode is a major degradation mechanism in lithium-ion batteries (LIBs). It brings a significant risk of internal shortcircuit by penetration of dendritic lithium through the separator, leading to short cycle life and safety issues. Understanding how and when plating occurs is crucial for the development of mitigation strategies, e. g. tuning the electrolyte composition. Here we present an operando X-ray tomographic microscopy (XTM) study to directly monitor the plating of lithium metal in a lithium/graphite cell. XTM enables a non-destructive and quantitative characterization at operando conditions of lithium deposition on a graphite electrode at relevant conditions. In this work it allows us to probe the role of the electrolyte additives vinylene carbonate (VC) and lithium bis(fluorosulfonyl)imide (LiFSI) in the standard LIB electrolyte LP57 (base electrolyte without additives). The additives show overall better performances in terms of delayed onset of lithium plating which is important for the utilisation of the full capacity of graphite intercallaiton. We show that there is a transition during lithiation of the dominating mechanism, once lithium plating is initiated this rapidly becomes dominating and hinders further intercalation. For the base electrolyte a homogeneous and dense morphology of plated lithium is found, whereas a more dendritic morphology is observed in the presence of additives. During delithiation, there is a rapid stripping of some of the plated lithium followed by deintercalation. In addition, our work provides a general methodology to track the morphology of plated lithium, which is crucial for fundamental research about battery safety.
|
|
| 8. |
- Lee, Suyeong, et al.
(author)
-
High-Energy and Long-Lifespan Potassium–Sulfur Batteries Enabled by Concentrated Electrolyte
- 2022
-
In: Advanced Functional Materials. - : Wiley. - 1616-3028 .- 1616-301X. ; 32:46
-
Journal article (peer-reviewed)abstract
- Potassium–sulfur (K–S) batteries are emerging as low-cost and high-capacity energy-storage technology. However, conventional K–S batteries suffer from two critical issues that have not yet been successfully resolved: the dissolution of potassium polysulfides (KPS) into the liquid electrolyte and the formation of K dendrites on the K metal anode, which lead to inadequate cycling efficiencies with a low reversible capacity. Herein, a high-capacity and long cycle-life K–S battery consisting of a highly concentrated electrolyte (HCE) (4.34 mol kg−1 potassium bis(fluorosulfonyl)imide in a 1,2-Dimethoxyethane) and a sulfurized polyacrylonitrile (SPAN) cathode is presented The application of a HCE efficiently suppresses the dendritic growth of K, as evidenced by operando optical imaging and phase field modeling, owing to the reduced K-ion depletion on the electrode surface and a uniform Faradaic current density over the K metal anode surface. Additionally, because S is covalently bonded to the C backbone of PAN in the SPAN structure, the SPAN cathode inhibits the dissolution of KPS. These features generate synergy that the proposed K–S battery can provide a practical areal capacity of 2.5 mAh cm−2 and unprecedented lifetimes with high Coulombic efficiencies over 700 cycles.
|
|
| 9. |
- Lee, Suyeong, et al.
(author)
-
Recent developments and future challenges in designing rechargeable potassium-sulfur and potassium-selenium batteries
- 2020
-
In: Energies. - : MDPI AG. - 1996-1073 .- 1996-1073. ; 13:11
-
Journal article (peer-reviewed)abstract
- The use of chalcogenide elements, such as sulfur (S) and selenium (Se), as cathode materials in rechargeable lithium (Li) and sodium (Na) batteries has been extensively investigated. Similar to Li and Na systems, rechargeable potassium-sulfur (K-S) and potassium-selenium (K-Se) batteries have recently attracted substantial interest because of the abundance of K and low associated costs. However, K-S and K-Se battery technologies are in their infancy because K possesses overactive chemical properties compared to Li and Na and the electrochemical mechanisms of such batteries are not fully understood. This paper summarizes current research trends and challenges with regard to K-S and K-Se batteries and reviews the associated fundamental science, key technological developments, and scientific challenges to evaluate the potential use of these batteries and finally determine effective pathways for their practical development.
|
|
| 10. |
- Liu, Qiao, et al.
(author)
-
Enhanced ionic conductivity and interface stability of hybrid solid-state polymer electrolyte for rechargeable lithium metal batteries
- 2019
-
In: Energy Storage Materials. - : Elsevier BV. - 2405-8297. ; 23, s. 105-111
-
Journal article (peer-reviewed)abstract
- Compared to conventional organic liquid electrolyte, solid-state polymer electrolytes are extensively considered as an alternative candidate for next generation high-energy batteries because of their high safety, non-leakage and electrochemical stability with the metallic lithium (Li) anode. However, solid-state polymer electrolytes generally show low ionic conductivity and high interfacial impedance to electrodes. Here we report a hybrid solid-state electrolyte, presenting an ultra-high ionic conductivity of 3.27 mS cm −1 at room temperature, a wide electrochemical stability window of 4.9 V, and non-flammability. This electrolyte consists of a polymer blend matrix (polyethylene oxide and poly (vinylidene fluoride-co-hexafluoropropylene)), Li + conductive ceramic filler (Li 1.5 Al 0.5 Ge 1.5 (PO 4 ) 3 ) and a solvate ionic liquid (LiFSI in tetra ethylene glycol dimethyl ether, 1:1 in molar ratio) as plasticizer. The introduction of the solvate ionic liquid to the solid-state electrolyte not only improves its ionic conductivity but also remarkably enhances the stability of the interface with Li anode. When applied in Li metal batteries, a Li|Li symmetric cell can operate stably over 800 h with a minimal polarization of 25 mV and a full Li|LiFePO 4 cell delivers a high specific capacity of 158 mAh g −1 after 100 cycles at room temperature.
|
|
