| 11. |
- Fretz, Samuel Joseph, 1987, et al.
(författare)
-
Amine- and Amide-Functionalized Mesoporous Carbons: A Strategy for Improving Sulfur/Host Interactions in Li-S Batteries
- 2020
-
Ingår i: Batteries and Supercaps. - : Wiley. - 2566-6223. ; 3:8, s. 757-765
-
Tidskriftsartikel (refereegranskat)abstract
- Lithium-sulfur (Li-S) batteries are of great interest due to their potentially high energy density, but the low electronic conductivity of both the sulfur (S-8) cathode active material and the final discharge product lithium sulfide (Li2S) require the use of a conductive host. Usually made of relatively hydrophobic carbon, such hosts are typically ill-suited to retain polar discharge products such as the intermediate lithium polysulfides (LiPs) and the final Li2S. Herein, we propose a route to increase the sulfur utilization by functionalizing the surface of ordered mesoporous carbon CMK3 with polar groups. These derivatized CMK3 materials are made using a simple two-step procedure of bromomethylation and subsequent nucleophilic substitution with amine or amide nucleophiles. We demonstrate that, compared to the unfunctionalized control, these modified CMK3 surfaces have considerably larger binding energies with LiPs and Li2S, which are proposed to aid the electrochemical conversion between S-8 and Li2S by keeping the LiPs species in close proximity to the carbon surface during Li-S battery cycling. As a result, the functionalized cathodes exhibit significantly improved specific capacities relative to their unmodified precursor.
|
|
| 12. |
- Gustafsson, Olof, et al.
(författare)
-
Design and Operation of an Operando Synchrotron Diffraction Cell Enabling Fast Cycling of Battery Materials
- 2021
-
Ingår i: Batteries & Supercaps. - : John Wiley & Sons. - 2566-6223. ; 4:10, s. 1599-1604
-
Tidskriftsartikel (refereegranskat)abstract
- Operation of a battery typically involves dynamic and non-equilibrium processes, making real time operando techniques crucial for understanding their nature. Operando X-ray diffraction is an important technique for investigating metastable intermediates and non-equilibrium phase transitions in crystalline electrode materials. Currently employed experimental setups often apply a disruptive approach to cell design, whereby the integrity of standard electrochemical cells is compromised to facilitate collection of high-quality diffraction data. Here, we present a non-disruptive approach to adapting the use of a standard pouch cell that enables fast and long-term cell cycling. Suitability of the setup is demonstrated on the well-studied cathode material LiNi0.5Mn1.5O4. While exhibiting comparable electrochemical behavior to a standard pouch cell up to a current rate of 8 C (∼6.6 mA cm−2), phase transitions could be monitored accurately. Thus, the cell provides a new alternative to investigating non-equilibrium transitions and long-term aging effects in battery materials.
|
|
| 13. |
- Hall, Charles Aram, et al.
(författare)
-
Revisiting Amides as Cosolvents for Flame Resistant Sodium Bis(oxalato)borate in Triethyl Phosphate Electrolyte
- 2024
-
Ingår i: Batteries & Supercaps. - : John Wiley & Sons. - 2566-6223. ; 7:1
-
Tidskriftsartikel (refereegranskat)abstract
- In selecting electrolytes for Na-ion batteries, simply importing the analogue of common lithium-ion battery electrolytes to sodium-ion batteries does not address safety concerns like toxicity and flammability. Electrolytes based on sodium bis(oxalato)borate (NaBOB) in organophosphates like triethyl phosphate (TEP) largely alleviate these specific safety concerns. However, it may be beneficial to obtain solutions with higher ionic conductivities than NaBOB in TEP, and compare the performance in Na-ion batteries with high mass loading electrodes. Here, we have shown that N,N-dimethyl formamide (DMF), N,N-dimethyl acetamide (DMAc), and N-methyl pyrrolidone (NMP) cosolvents almost double the ionic conductivity (from similar to 3.5 mS/cm to similar to 7 mS/cm) without sacrificing the flame-retarding properties of the base NaBOB in TEP electrolyte. The physical properties of these cosolvent electrolyte mixtures are investigated, along with the electrochemical performance of these electrolytes full-cells based on hard carbon anodes and Prussian white cathodes with near-commercial areal capacity (similar to 2 mAh/cm(2)).
|
|
| 14. |
- Hernández, Guiomar, et al.
(författare)
-
Fluorine-Free Electrolytes for Lithium and Sodium Batteries
- 2022
-
Ingår i: Batteries & Supercaps. - : John Wiley & Sons. - 2566-6223. ; 5:6
-
Forskningsöversikt (refereegranskat)abstract
- Fluorinated components in the form of salts, solvents and/or additives are a staple of electrolytes for high-performance Li- and Na-ion batteries, but this comes at a cost. Issues like potential toxicity, corrosivity and environmental concerns have sparked interest in fluorine-free alternatives. Of course, these electrolytes should be able to deliver performance that is on par with the electrolytes being in use today in commercial batteries. This begs the question: Are we there yet? This review outlines why fluorine is regarded as an essential component in battery electrolytes, along with the numerous problems it causes and possible strategies to eliminate it from Li- and Na-ion battery electrolytes. The examples provided demonstrate the possibilities of creating fully fluorine-free electrolytes with similar performance as their fluorinated counterparts, but also that there is still a lot of room for improvement, not least in terms of optimizing the fluorine-free systems independently of their fluorinated predecessors.
|
|
| 15. |
- Jankowski, Piotr, 1990, et al.
(författare)
-
Designing High-Performant Lithium Battery Electrolytes by Utilizing Two Natures of Li+ Coordination: LiTDI/LiTFSI in Tetraglyme
- 2021
-
Ingår i: Batteries and Supercaps. - : Wiley. - 2566-6223. ; 4:4, s. 205-213
-
Tidskriftsartikel (refereegranskat)abstract
- Highly concentrated electrolytes (HCEs) based on glymes, such as tetraglyme (G4), are currently the focus of much battery research, primarily due to their unique properties - especially with respect to ion transport and electrochemical stability. While the LiTFSI-G4 and LiTDI-G4 systems both have been studied extensively, we here design their hybrid electrolytes to answer; will the resulting properties be averages/superpositions or will there be synergies created? We find the latter to be true and demonstrate that the most performant electrolytes are obtained by introducing a minor amount of LiTDI to an LiTFSI based electrolyte, which promotes the disproportionation and formation of "free" cations and at the same to avoid large aggregates - shown comprehensively both experimentally and by different modelling approaches and analyses combined. This electrolyte composition strategy can be generalized to other salts and solvents and thus a route towards a flora of novel battery electrolytes is here suggested.
|
|
| 16. |
- Jankowski, Piotr, 1990, et al.
(författare)
-
Prospects for Improved Magnesocene-Based Magnesium Battery Electrolytes
- 2021
-
Ingår i: Batteries and Supercaps. - : Wiley. - 2566-6223. ; 4:8, s. 1335-1343
-
Tidskriftsartikel (refereegranskat)abstract
- Magnesium batteries are currently attracting a lot of interest as a next generation battery technology. One critical issue is to find a suitable electrolyte and herein we explore an electrolyte based on magnesocene (MgCp2) in tetrahydrofuran (THF), aiming for low-voltage Mg batteries, with respect to: Mg plating characteristics, electrochemical stability windows, electrolyte speciation, and electrolyte decomposition reactions; both experimentally and computationally. Overall, the electrolyte does not seem to decompose on a Mg metal anode and most likely reduced solvation of Mg2+ by the Cp- anion is important and species such as MgCp2THF2 may play an important role for Mg plating with small overpotential. The oxidation limit is largely determined by the Cp- anion and density functional theory predicted oxidation reactions point to polymerized end-products to be possible. Furthermore, in silico substitution studies enable us to establish the prospects of some Cp- anion derivatives to further improve the oxidative stability, but still the Mg2+ solvation must be monitored for ease of reduction and Mg plating.
|
|
| 17. |
- Jeschke, Steffen, 1986, et al.
(författare)
-
Supervised Machine Learning-Based Classification of Li-S Battery Electrolytes
- 2021
-
Ingår i: Batteries and Supercaps. - : Wiley. - 2566-6223. ; 4:7, s. 1156-1162
-
Tidskriftsartikel (refereegranskat)abstract
- Machine learning (ML) approaches have the potential to create a paradigm shift in science, especially for multi-variable problems at different levels. Modern battery R&D is an area intrinsically dependent on proper understanding of many different molecular level phenomena and processes alongside evaluation of application level performance: energy, power, efficiency, life-length, etc. One very promising battery technology is Li-S batteries, but the polysulfide solubility in the electrolyte must be managed. Today, many different electrolyte compositions and concepts are evaluated, but often in a more or less trial-and-error fashion. Herein, we show how supervised ML can be applied to accurately classify different Li-S battery electrolytes a priori based on predicting polysulfide solubility. The developed framework is a combined density functional theory (DFT) and statistical mechanics (COSMO-RS) based quantitative structure-property relationship (QSPR) model which easily can be extended to other battery technologies and electrolyte properties.
|
|
| 18. |
- Johansson, Isabell L., et al.
(författare)
-
Mechanically Stable UV-Crosslinked Polyester-Polycarbonate Solid Polymer Electrolyte for High-Temperature Batteries
- 2020
-
Ingår i: Batteries & Supercaps. - : WILEY-V C H VERLAG GMBH. - 2566-6223. ; 3:6, s. 527-533
-
Tidskriftsartikel (refereegranskat)abstract
- Due to the mechanism with which solid polymer electrolytes use to conduct ions, these materials are generally more suitable for high-temperature applications where the ionic conductivity is sufficient and where liquid electrolytes show insufficient stability. To enable high-temperature cycling of polymer electrolytes, the mechanical stability has to be improved. Herein, we report successful long-term cycling of a solid polyester-polycarbonate - poly(epsilon-caprolactone-co-trimethylene carbonate) (poly(CL-co-TMC)) - electrolyte cross-linked through the addition of multifunctional acrylates and the use of UV-irradiation, allowing stable cycling of cells for more than 100 cycles at 80 degrees C, with good rate capabilities (0.2 mA cm(-2)) and Coulombic efficiencies exceeding 99 %. Both the mechanical properties and the ionic conductivity of the mechanically stabilized poly(CL-co-TMC) were investigated and optimized to reduce the frequency dependence of the moduli while still achieving an acceptable ionic conductivity at elevated temperature. These results indicate that the poly(CL-co-TMC) system can straight-forwardly be modified to allow for higher-temperature applications.
|
|
| 19. |
- Johansson, Patrik, 1969, et al.
(författare)
-
Ten Ways to Fool the Masses When Presenting Battery Research
- 2021
-
Ingår i: Batteries and Supercaps. - : Wiley. - 2566-6223. ; 4:12, s. 1785 -1788
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- As scientists within the field of battery research we may often find it quite difficult to match and trust the promises given in press releases and high-profile papers. Even though there are real breakthroughs, where the results indeed are as impressive as they are marketed to be, we may as often find the reporting of "revolutionary" results to omit critical aspects of the methods and materials used. The absolute majority of researchers do not actively pursue to present their science in any untrue fashion, but poor (ethical) judgement could affect anyone working long hours in a gloomy lab at dusk and at the same time feel being pressed for publications and citations. Here, we outline ten ways to make your results appear more attractive and ground-breaking than they actually are, especially to laypeople that might not appreciate the full range of difficulties associated with battery research. Consider it a light-hearted entry with respect to scientific quality in methodology and dissemination, that might assist you in looking for nebulous reporting practices in your own and your peers' work, but please do not consider it a guide, but a humorous contrast to the real publishing guidelines recently launched
|
|
| 20. |
- Karlsmo, Martin, 1995, et al.
(författare)
-
Sustainability and Technical Performance of An All-Organic Aqueous Sodium-Ion Hybrid Supercapacitor
- 2022
-
Ingår i: Batteries and Supercaps. - : Wiley. - 2566-6223.
-
Tidskriftsartikel (refereegranskat)abstract
- Development of all-organic aqueous energy storage devices (ESDs) is a promising pathway towards meeting the needs of technically medium/low-demanding electrical applications. Such ESDs should favour low cost, low environmental impact, and safety, and thereby complement more expensive, high voltage, and energy/power dense ESDs such as lithium-ion batteries. Herein, we set out to assemble all-organic aqueous Na-ion hybrid supercapacitors, exclusively using commercial materials, with the aim to provide a truly sustainable and lowcost ESD. Overall, the created ESD delivers adequate technical performance in terms of capacity retention, Coulombic efficiency, energy efficiency, and energy/power density. Finally, we apply a straight-forward and qualitative biodegradability method to the ESD.
|
|
