| 1. |
- Benitez, Almudena, et al.
(författare)
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Recent advances in lithium-sulfur batteries using biomass-derived carbons as sulfur host
- 2022
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Ingår i: Renewable & sustainable energy reviews. - : Elsevier. - 1364-0321 .- 1879-0690. ; 154
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Tidskriftsartikel (refereegranskat)abstract
- While biomass waste is generated in abundance, these materials and their production processes are generally environmentally friendly, low cost, non-hazardous and easily scalable. These advantages position biomass materials as excellent candidates to solve problems of environmental pollution, primarily by substitution of less sustainable counterparts. This also applies to energy storage systems such as batteries, where several components have large environmental impacts. Lithium-Sulfur batteries have, in this context, been extensively researched to cope with the growing energy needs, and are expected to foresee a growing commercialization. Specifically, advances in the use of renewable cathode materials for Li-S batteries is a field that has been widely addressed in recent years, with carbonaceous materials (C) and/or activated carbons (AC), obtained from biomass, being intensively studied. We here reviewed this field through a classification and discussion of carbonaceous materials from natural waste according to the type of biomass: (1) woody, (2) herbaceous and agricultural, (3) aquatic, (4) animal and human, and (5) contaminated and industrial biomass waste materials. In addition, all porous carbons or activated carbons used as sulfur hosts have been exhaustively evaluated in terms of origin, synthesis parameters, physical properties, and electrochemical performance in Li-S batteries. The purpose is to provide a general description of the progress in the preparation of carbons from biomass resources, examine the textural and electrochemical properties of these materials focusing on the last decade, and also to present an outlook for future research in this developing area.
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| 2. |
- Brant, William R., et al.
(författare)
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Local structure transformations promoting high lithium diffusion in defect perovskite type structures
- 2023
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Ingår i: Electrochimica Acta. - : Elsevier. - 0013-4686 .- 1873-3859. ; 441
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Tidskriftsartikel (refereegranskat)abstract
- Defect perovskites, AxBO3 such as (Li3xLa2/3-x)TiO3, are attracting attention as high capacity electrodes in lithium-ion batteries. However, the mechanism enabling high lithium storage capacities has not been fully investigated. In this work, the reversible insertion and removal of lithium up to an average A-site cavity occupancy of 1.71 in the defect perovskite (Li0.18Sr0.66)(Ti0.5Nb0.5)O3 is investigated. It was shown that subtle lithium reorganization during lithiation has a significant impact on enabling high capacity. Contrary to previous studies, lithium was coordinated to triangular faces of Ti/Nb oxygen octahedra and offset from O4 windows between A-site cavities in the as-synthesised material. Upon electrochemical lithiation Li-Li repulsion redistributes of all the lithium towards the O4 window position resulting in a loss of lithium mobility. Surprisingly, the mobility is regained during over-lithiation and following multiple electrochemical cycles. It is suggested that lithium reorganisation into the center of the O4 window alleviates the Li-Li repulsion and modifies the diffusion behavior from site percolation to bond percolation. The results obtained provide valuable insight into the chemical drivers enabling higher capacities and enhanced diffusion in defect perovskites. More broadly the study delivers fundamental understanding on the non-equilibrium structural transformations occurring within electrode materials during repeated electrochemical cycles.
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| 3. |
- Chien, Yu-Chuan, 1990-, et al.
(författare)
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Cellulose Separators With Integrated Carbon Nanotube Interlayers for Lithium-Sulfur Batteries : An Investigation into the Complex Interplay between Cell Components
- 2019
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Ingår i: Journal of the Electrochemical Society. - : The Electrochemical Society. - 0013-4651 .- 1945-7111. ; 166:14, s. A3235-A3241
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Tidskriftsartikel (refereegranskat)abstract
- This work aims to address two major roadblocks in the development of lithium-sulfur (Li-S) batteries: the inefficient deposition of Li on the metallic Li electrode and the parasitic "polysulfide redox shuttle". These roadblocks are here approached, respectively, by the combination of a cellulose separator with a cathode-facing conductive porous carbon interlayer, based on their previously reported individual benefits. Both approaches result in significant improvements in cycle life in test cells with positive electrodes with practically relevant specifications. Despite the substantially prolonged cycle life, the combination of the interlayer and cellulose separator generates an increase in polysulfide shuttle current, leading to greatly reduced Coulombic efficiency. Based on XPS analyses, the latter is ascribed to a change in the composition of the solid electrolyte interphase (SEI) on the Li electrode. At the same time, the rate of electrolyte decomposition is found to be lower in cells with cellulose-based separators, which corroborates the observation of longer cycle life. These seemingly contradictory and counterintuitive observations demonstrate the complicated interactions between the cell components in the Li-S system and how strategies aiming to mitigate one unwanted process may exacerbate another. This study demonstrates the value of a holistic approach to the development of Li-S chemistry.
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| 4. |
- Chien, Yu-Chuan, 1990-, et al.
(författare)
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Correlations between precipitation reactions and electrochemical performance of lithium-sulfur batteries probed by operando scattering techniques
- 2022
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Ingår i: Chem. - : Elsevier. - 2451-9294. ; 8:5
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Tidskriftsartikel (refereegranskat)abstract
- A comprehensive description of electrochemical processes in the positive electrode of lithium-sulfur batteries is crucial for the utilization of active material. However, the discharge mechanisms are complicated due to various reactions in multiple phases and the tortuosity of the highly porous carbon matrix. In this work, simultaneous measurements of small-angle and wide-angle scattering and cell resistance are performed on operating lithium-sulfur cells. Results indicate that precipitates grow mostly in number, not in size, and that the structure of the carbon matrix is not affected. The comparison of the small-angle and wide-angle scattering reveals the amorphous discharge products found at a low discharge rate. Further analysis demonstrates the correlation between the diffusion resistance and the compositional change of electrolyte in the mesopores at the end of discharge, which suggests that Li-ion deficiency is the limiting factor for sulfur utilization at a medium discharge rate.
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| 5. |
- Chien, Yu-Chuan, 1990-, et al.
(författare)
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Electrochemical Analysis of Modified Separators for Li-S Batteries
- 2018
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The lithium-sulfur system is one of the potential energy storage technologies of the next generation due to the high theoretical specific capacity (1672 mAh/g), abundance and nontoxicity of sulfur [1]. However, there are still challenges yet to be overcome, one of which is the ‘polysulfide shuttle’ [1]. In order to address this issue, several modifications of the separators have been proposed. For example, longer cycle life, higher Coulombic efficiency and higher specific capacities have been reported with metal oxide coatings [2] and conductive interlayers [3,4] on the separators. Performance improvements in one or more of these properties have been ascribed to a suppression of polysulfide transport across the separator, even though this has not always been correlated with the difference in electrochemistry. In this work, the Intermittent Current Interruption (ICI) method [5] is applied to monitor the evolution of internal resistance of Li-S cells with different separators during repeated charge and discharge. Cells with different separators exhibit significant differences in resistance as a function of state-of-charge in the initial cycles, as shown in the figure. Complemented by self-discharge tests and impedance spectroscopy at selected states of charge, the roles of the interlayers in the system can be further interpreted electrochemically. This work aims to associate the electrochemical properties of the interlayers to their corresponding microstructural counterparts, which can in turn facilitate further development of the interlayer materials. Figure: Internal resistance of cells vs specific charge for Li-S cells with different separators (Zero charge indicates the fully charged state.) for the 2nd, 5th and 10th cycles at C/10 rate. References:[1] S. Urbonaite, T. Poux, P. Novák, Adv. Energy Mater. 5 (2015) 1–20.[2] Z. Zhang, Y. Lai, Z. Zhang, K. Zhang, J. Li, Electrochim. Acta 129 (2014) 55–61.[3] H. Yao, K. Yan, W. Li, G. Zheng, D. Kong, Z.W. Seh, V.K. Narasimhan, Z. Liang, Y. Cui, Energy Environ. Sci. 7 (2014) 3381–3390.[4] J. Balach, T. Jaumann, M. Klose, S. Oswald, J. Eckert, L. Giebeler, Adv. Funct. Mater. 25 (2015) 5285–5291.[5] M.J. Lacey, K. Edström, D. Brandell, Chem. Commun. 51 (2015) 16502–16505.
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| 6. |
- Chien, Yu-Chuan, 1990-, et al.
(författare)
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Impact of Compression on the Electrochemical Performance of the Sulfur/Carbon Composite Electrode in Lithium-Sulfur Batteries
- 2022
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Ingår i: Batteries & Supercaps. - : Wiley-VCH Verlagsgesellschaft. - 2566-6223. ; 5:7
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Tidskriftsartikel (refereegranskat)abstract
- While lithium-sulfur batteries theoretically have both high gravimetric specific energy and volumetric energy density, only its specific energy has been experimentally demonstrated to surpass that of the state-of-the-art lithium-ion systems at cell level. One major reason for the unrealized energy density is the low capacity density of the highly porous sulfur/carbon composite as the positive electrode. In this work, mechanical compression at elevated temperature is demonstrated to be an effective method to increase the capacity density of the electrode by at least 90 % and moreover extends its cycle life. Distinct impacts of compression on the resistance profiles of electrodes with different thickness are investigated by tortuosity factors derived from both electrochemical impedance spectroscopy, X-ray computed tomography and kinetic analysis based on operando X-ray diffraction. The results highlights the importance of a homogeneous electrode structure highlight lithium-sulfur system.
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| 7. |
- Chien, Yu-Chuan, 1990-, et al.
(författare)
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Mechanistic Insights on the Mesoscale in the Positive Electrode of Lithium–Sulfur Batteries
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- A comprehensive description of the electrochemical processes in the positive electrodeof lithium–sulfur batteries is critical to the enhancement of sulfur utilization. However,the discharge mechanisms are complicated due to the various reactions in multiplephases and the tortuosity of the highly porous carbon matrix. While previous studieshave focused on the precipitation of Li2S, the effect of the limited mass transport insidethe micro-/mesopores of an electrode with optimized surface area have largely beenneglected. In this work, operando small-angle scattering with three different contrasts,and wide-angle scattering, has been performed with simultaneous resistance measure-ment of internal and diffusion. The results indicate that both electrode passivation andcomplete pore blockage are unlikely since the precipitates are surrounded by the elec-trolyte and grow mostly in number, not in size. The difference between the small- andwide-angle scattering reveals the amorphous discharge products at a low C-rate. Furtheranalyses demonstrate the correlation between the diffusion resistance and the contrastin the mesopores at the end of discharge, which suggests that Li-ion deficiency is thelimiting factor of sulfur utilization at a medium C-rate.
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| 8. |
- Chien, Yu-Chuan, 1990-
(författare)
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Operando Characterisation of Lithium–Sulfur Batteries
- 2021
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Lithium–sulfur (Li–S) batteries have been under the spotlight of research on electrochemical energy storage systems, primarily owing to their high theoretical specific energy (2552 Wh kg-1). So far, Li–S cells on the market have presented a specific energy of 400 Wh kg-1, which is superior to many commercial alternatives, but far below the theoretical value. At the same time, Li–S batteries encounter other problems that are generally not associated with the standard Li-ion batteries, such as low utilisation rate of active materials and short cycle life. These often originate from the unique catholyte nature and/or the low reversibility of the metallic Li electrode.The dissolution and precipitation of elemental sulfur and lithium sulfide in the positive electrode are here investigated by operando X-ray diffraction (XRD) and small-angle neutron/X-ray scattering (SANS/SAXS) coupled with the Intermittent Current Interruption (ICI) method. The real-time internal and diffusion resistances are correlated to the kinetics of the precipitation of the crystalline species by operando XRD. Through operando SANS and SAXS, the formation of crystalline and amorphous solid-state discharge products and the compositional variation of catholyte inside the mesopores are linked to features in the resistance profiles. These studies indicate that the ionic transport limitation inside the positive electrode is the cause for the low sulfur utilisation during battery discharge.To examine the impact of the repetitive precipitation on the functionality of the positive sulfur electrode, a method based on electrochemical impedance spectroscopy (EIS) was developed to track the electrochemically active surface area of the carbon matrix in-situ over extensive cycling. The investigation found no progressive passivation on the positive electrode despite the rapid decrease in specific discharge capacity. Additionally, a novel three-electrode setup for Li–S cells reveals a faster growth of the resistance on the metallic Li electrode along cycling. These findings suggest that primarily the negative electrode limits the cycle life. Through providing the mechanistic insights of operational Li–S cells, this thesis demonstrates the value of simultaneous electrochemical and materials characterisations for understanding the complex Li–S system.
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| 9. |
- Chien, Yu-Chuan, 1990-, et al.
(författare)
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Poly(Ethylene Glycol-block-2-Ethyl-2-Oxazoline) as Cathode Binder in Lithium-Sulfur Batteries
- 2021
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Ingår i: ChemistryOpen. - : John Wiley & Sons. - 2191-1363. ; 10:10, s. 960-965
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Tidskriftsartikel (refereegranskat)abstract
- Functional binders constitute a strategy to overcome several challenges that lithium-sulfur (Li-S) batteries are facing due to soluble reaction intermediates in the positive electrode. Poly (ethylene oxide) (PEO) and poly (vinylpyrrolidone) (PVP) are in this context a previously well-explored binder mixture. Their ether and amide groups possess affinity to the dissolved sulfur species, which enhances the sulfur utilization and mitigates the parasitic redox shuttle. However, the immiscibility of PEO and PVP is a concern for electrode stability. Copolymers comprising ether and amide groups are thus promising candidates to improve the stability the system. Here, a series of poly (ethylene glycol-block-2-ethyl-2-oxazoline) with various block lengths is synthesized and explored as binders in S/C composite electrodes in Li-S cells. While the electrochemical analyses show that although the sulfur utilization and capacity retention of the tested electrodes are similar, the integrity of the as-cast electrodes can play a key role for power capability.
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| 10. |
- Chien, Yu-Chuan, 1990-, et al.
(författare)
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Rapid determination of solid-state diffusion coefficients in Li-based batteries via intermittent current interruption method
- 2023
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Ingår i: Nature Communications. - : Springer Nature. - 2041-1723. ; 14:1
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Tidskriftsartikel (refereegranskat)abstract
- The galvanostatic intermittent titration technique (GITT) is considered the go-to method for determining the Li+ diffusion coefficients in insertion electrode materials. However, GITT-based methods are either time-consuming, prone to analysis pitfalls or require sophisticated interpretation models. Here, we propose the intermittent current interruption (ICI) method as a reliable, accurate and faster alternative to GITT-based methods. Using Fick’s laws, we prove that the ICI method renders the same information as the GITT within a certain duration of time since the current interruption. Via experimental measurements, we also demonstrate that the results from ICI and GITT methods match where the assumption of semi-infinite diffusion applies. Moreover, the benefit of the non-disruptive ICI method to operando materials characterization is exhibited by correlating the continuously monitored diffusion coefficient of Li+ in a LiNi0.8Mn0.1Co0.1O2-based electrode to its structural changes captured by operando X-ray diffraction measurements.
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| 11. |
- Chien, Yu-Chuan, 1990-, et al.
(författare)
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Simultaneous Monitoring of Crystalline Active Materials and Resistance Evolution in Lithium-Sulfur Batteries
- 2020
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Ingår i: Journal of the American Chemical Society. - : AMER CHEMICAL SOC. - 0002-7863 .- 1520-5126. ; 142:3, s. 1449-1456
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Tidskriftsartikel (refereegranskat)abstract
- Operando X-ray diffraction (XRD) is a valuable tool for studying secondary battery materials as it allows for the direct correlation of electrochemical behavior with structural changes of crystalline active materials. This is especially true for the lithium-sulfur chemistry, in which energy storage capability depends on the complex growth and dissolution kinetics of lithium sulfide (Li2S) and sulfur (S-8) during discharge and charge, respectively. In this work, we present a novel development of this method through combining operando XRD with simultaneous and continuous resistance measurement using an intermittent current interruption (ICI) method. We show that a coefficient of diffusion resistance, which reflects the transport properties in the sulfur/carbon composite electrode, can be determined from analysis of each current interruption. Its relationship to the established Warburg impedance model is validated theoretically and experimentally. We also demonstrate for an optimized electrode formulation and cell construction that the diffusion resistance increases sharply at the discharge end point, which is consistent with the blocking of pores in the carbon host matrix. The combination of XRD with ICI allows for a direct correlation of structural changes with not only electrochemical properties but also energy loss processes at a nonequilibrium state and, therefore, is a valuable technique for the study of a wide range of energy storage chemistries.
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| 12. |
- Chien, Yu-Chuan, 1990-, et al.
(författare)
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Towards reliable three-electrode cells for lithium–sulfur batteries
- 2022
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Ingår i: Chemical Communications. - : Royal Society of Chemistry (RSC). - 1359-7345 .- 1364-548X. ; 58:5, s. 705-708
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Tidskriftsartikel (refereegranskat)abstract
- Three-electrode measurements are valuable to the understanding of the electrochemical processes in a battery system. However, their application in lithium–sulfur chemistry is difficult due to the complexity of the system and thus rarely reported. Here, we present a simple three-electrode cell format with relatively good life time and minimum interference with the cell operation.
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| 13. |
- Chien, Yu-Chuan, 1990-, et al.
(författare)
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Understanding the Impact of Precipitation Kinetics on the Electrochemical Performance of Lithium–Sulfur Batteries by Operando X-ray Diffraction
- 2022
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Ingår i: The Journal of Physical Chemistry C. - : American Chemical Society (ACS). - 1932-7447 .- 1932-7455. ; 126:6, s. 2971-2979
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Tidskriftsartikel (refereegranskat)abstract
- The complex reaction mechanism of the lithium–sulfur battery system consists of re-petitive dissolution and precipitation of the sulfur-containing species in the positiveelectrode. In particular, the precipitation of lithium sulfide (Li2S) during discharge hasbeen considered a crucial factor for achieving a high degree of active material utiliza-tion. Here, the influence of electrolyte amount, electrode thickness, applied current andelectrolyte salt on the formation of Li2S is systematically investigated in a series ofoperando X-ray diffraction experiments. Through a combination of simultaneous dif-fraction and resistance measurements, the evolution of the intensity from Li2S is di-rectly correlated to the variation in internal resistance and transport properties insidethe positive electrode. The correlation indicates that at different stages, the Li2S precip-itation both facilitates and impedes the discharge process. The kinetic information ofLi2S formation offers mechanistic explanations for the strong impact of different elec-trochemical cell parameters on the performance and thus, directions for holistic optimi-zations to achieve high sulfur utilization.
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| 14. |
- Hernández, Guiomar, et al.
(författare)
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Elimination of Fluorination : The Influence of Fluorine-Free Electrolytes on the Performance of LiNi1/3Mn1/3Co1/3O2/Silicon-Graphite Li-Ion Battery Cells
- 2020
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Ingår i: ACS Sustainable Chemistry and Engineering. - : AMER CHEMICAL SOC. - 2168-0485. ; 8:27, s. 10041-10052
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Tidskriftsartikel (refereegranskat)abstract
- In the quest for environmentally friendly and safe batteries, moving from fluorinated electrolytes that are toxic and release corrosive compounds, such as HF, is a necessary step. Here, the effects of electrolyte fluorination are investigated for full cells combining silicon- graphite composite electrodes with Li-Ni1/3Mn1/3Co1/3O2 (NMC111) cathodes, a viable cell chemistry for a range of potential battery applications, by means of electrochemical testing and postmortem surface analysis. A fluorine-free electrolyte based on lithium bis(oxalato) borate (LiBOB) and vinylene carbonate (VC) is able to provide higher discharge capacity (147 mAh g(NMC)(-1)) and longer cycle life at C/10 (84.4% capacity retention after 200 cycles) than a cell with a highly fluorinated electrolyte containing LiPF6, fluoroethylene carbonate (FEC) and VC. The cell with the fluorine-free electrolyte is able to form a stable solid electrolyte interphase (SEI) layer, has low overpotential, and shows a slow increase in cell resistance that leads to improved electrochemical performance. Although the power capability is limiting the performance of the fluorine-free electrolyte due to higher interfacial resistance, it is still able to provide long cycle life at C/2 and outperforms the highly fluorinated electrolyte at 40 degrees C. X-ray photoelectron spectroscopy (XPS) results showed a F-rich SEI with the highly fluorinated electrolyte, while the fluorine-free electrolyte formed an O-rich SEI. Although their composition is different, the electrochemical results show that both the highly fluorinated and fluorine-free electrolytes are able to stabilize the silicon-based anode and support stable cycling in full cells. While these results demonstrate the possibility to use a nonfluorinated electrolyte in high-energy-density full cells, they also address new challenges toward environmentally friendly and nontoxic electrolytes.
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| 15. |
- Li, He, et al.
(författare)
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Operando Characterization of Active Surface Area and Passivation Effects on Sulfur-Carbon Composites for Lithium-Sulfur Batteries
- 2022
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Ingår i: Electrochimica Acta. - : Elsevier. - 0013-4686 .- 1873-3859. ; 403
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Tidskriftsartikel (refereegranskat)abstract
- Sulfur electrodes for lithium-sulfur batteries necessarily contain a conductive additive,typically carbon, to enable the electrochemical reactions, since sulfur and the dischargeproduct, Li2S, are insulators. Consequently, the full passivation of carbon, by depositionof sulfur and/or Li2S, would necessarily produce the death of the battery. However, herewe demonstrate that for high-performance lithium-sulfur batteries operated under leanelectrolyte conditions (electrolyte to sulfur ratio of 6 µL mgS-1 in Li-S coin cells), theextent of passivation of carbon is not severe enough to limit performance. This is shownby performing impedance measurements of fully charged lithium-sulfur batteries, fromwhich we demonstrate that we can evaluate the specific surface area of carbon, and wefind that the capacity fade with cycling is not due to a decrease in the electrochemicallyactive specific surface area of carbon. These results show that introducing a higher sur-face area carbon in the sulfur electrode formulation is not needed to prevent passivation,and that the focus of lithium-sulfur development should be directed towards other is-sues, such as mitigating undesirable reactions at the lithium electrode and achievingrobust sulfur electrode structures enabling fast transport of electrolyte species and, thus,more homogeneous reactions.
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| 16. |
- Valvo, Mario, et al.
(författare)
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Detecting voltage shifts and charge storage anomalies by iron nanoparticles in three-electrode cells based on converted iron oxide and lithium iron phosphate
- 2023
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Ingår i: Electrochimica Acta. - : Elsevier BV. - 0013-4686 .- 1873-3859. ; 440
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Tidskriftsartikel (refereegranskat)abstract
- Noticeable voltage shifts have been observed in the charge/discharge profiles of a three-electrode cell with a lithium metal reference electrode and having a deeply lithiated iron oxide (Fe/Li2O) negative electrode galvanostatically cycled in a limited potential range against a positive LiFePO4 counterpart. The origin of such shifts has been attributed to charge storage anomalies in the Fe/Li2O nanocomposite due to characteristic reduced Fe nanoparticle sizes. These shifts also affected the extreme points of the voltage profiles of the positive electrode, which was also independently monitored. A combined evaluation of voltage profile slippages with possible changes in internal resistance and/or Li+ inventory loss, including an aimed analysis of current interruptions at the end of each lithiation/de-lithiation half-cycle to monitor the internal resistance and diffusion resistance coefficient of the Fe/Li2O electrode, has enabled a clarification of its altered charge storage. An asymmetric behaviour of the Fe/Li2O electrode during Li+ uptake/release has been revealed, highlighting a progressive, diffusion-controlled-type voltage drift at low potentials vs. Li+/Li, and an unusual tendency to slight oxidation with capacitive variations during the reverse electrochemical processes at higher voltages, instead.
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| 17. |
- Yin, Litao, et al.
(författare)
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Implementing intermittent current interruption into Li-ion cell modelling for improved battery diagnostics
- 2022
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Ingår i: Electrochimica Acta. - : Elsevier BV. - 0013-4686 .- 1873-3859. ; 427
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Tidskriftsartikel (refereegranskat)abstract
- A novel electroanalytical method, the intermittent current interruption (ICI) technique, has recently been promoted as a versatile tool for battery analysis and diagnostics. The technique enables frequent and continuous measurement of battery resistance, which then undergoes statistical analysis. Here, this method is implemented for commercial Li-ion cylindrical cells, and combined with a physics-based finite element model (FEM) of the battery to better interpret the measured resistances. Ageing phenomena such as solid electrolyte interphase (SEI) formation and metallic Li plating on the surface of the negative graphite particles are considered in the model. After validation, a long-term cycling simulation is conducted to mimic the ageing scenario of commercial cylindrical 21700 cells. The large number of internal resistance measurements obtained are subsequently visualized by creating a ‘resistance map’ as a function of both capacity and cycle numbers, providing a straight-forward image of their continuous evolution. By correlating the observed ageing scenarios with specific physical processes, the origins of ageing are investigated. The result shows that a decrease of the electrolyte volume fraction contributes significantly to the increase of internal resistance and affect the electrolyte diffusivity properties. Additionally, effects of porosity and particle radius of the different electrodes are investigated, providing valuable suggestions for battery design.
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