uu.seUppsala University Publications
Change search
Link to record
Permanent link

Direct link
BETA
Gustafsson, TorbjörnORCID iD iconorcid.org/0000-0003-2737-4670
Alternative names
Publications (10 of 152) Show all publications
Liu, C., Carboni, M., Brant, W., Pan, R., Hedman, J., Zhu, J., . . . Younesi, R. (2018). On the Stability of NaO2 in Na–O2 Batteries. ACS Applied Materials and Interfaces, 10(16), 13534-13541
Open this publication in new window or tab >>On the Stability of NaO2 in Na–O2 Batteries
Show others...
2018 (English)In: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 10, no 16, p. 13534-13541Article in journal (Refereed) Published
Abstract [en]

Na–O2 batteries are regarded as promising candidates for energy storage. They have higher energy efficiency, rate capability, and chemical reversibility than Li–O2 batteries; in addition, sodium is cheaper and more abundant compared to lithium. However, inconsistent observations and instability of discharge products have inhibited the understanding of the working mechanism of this technology. In this work, we have investigated a number of factors that influence the stability of the discharge products. By means of in operando powder X-ray diffraction study, the influence of oxygen, sodium anode, salt, solvent, and carbon cathode were investigated. The Na metal anode and an ether-based solvent are the main factors that lead to the instability and decomposition of NaO2 in the cell environment. This fundamental insight brings new information on the working mechanism of Na–O2 batteries.

Keywords
metal-air battery, in operando X-ray diffraction, sodium superoxide, NaO2, decomposition
National Category
Materials Chemistry
Identifiers
urn:nbn:se:uu:diva-356097 (URN)10.1021/acsami.8b01516 (DOI)000431150900032 ()29616791 (PubMedID)
Funder
Swedish Research CouncilSwedish Energy AgencyStandUpÅForsk (Ångpanneföreningen's Foundation for Research and Development)
Available from: 2018-07-19 Created: 2018-07-19 Last updated: 2018-10-05Bibliographically approved
Xu, C., Jeschull, F., Brant, W. R., Brandell, D., Edström, K. & Gustafsson, T. (2018). The Role of LiTDI Additive in LiNi1/3Mn1/3Co1/3O2/ Graphite Lithium-Ion Batteries at Elevated Temperatures. Journal of the Electrochemical Society, 165(2), A40-A46
Open this publication in new window or tab >>The Role of LiTDI Additive in LiNi1/3Mn1/3Co1/3O2/ Graphite Lithium-Ion Batteries at Elevated Temperatures
Show others...
2018 (English)In: Journal of the Electrochemical Society, ISSN 0013-4651, E-ISSN 1945-7111, Vol. 165, no 2, p. A40-A46Article in journal (Refereed) Published
Abstract [en]

The poor thermal stability of conventional LiPF6-based electrolytes is one of the major obstacles for today's lithium-ion batteries. Recently, lithium 4,5-dicyano-2-( trifluoromethyl) imidazolide (LiTDI) has demonstrated to be highly efficient in scavenging moisture from the electrolyte and thereby improving electrolyte stability. In this context, effects of the LiTDI additive on LiNi1/3Mn1/3Co1/3O2 (NMC)/graphite cells are evaluated at a temperature of 55 degrees C. With the incorporation of LiTDI, an improved cycling performance of NMC/graphite cells was achieved, and the impedance increase at the NMC/electrolyte interface was significantly mitigated. Furthermore, LiTDI exhibited a profound influence on the interfacial chemistries in the full cell, and LiTDI-derived species were found on the surfaces of both the cathode and the anode. The SEI layer formed on graphite anodes was more homogenous in morphology and consisted of larger amounts of LiF and fewer oxygen-containing species, as compared to graphite in additive-free cells. This study shows that LiTDI is a promising electrolyte additive for NMC/graphite cells operated at elevated temperatures, highlighting that the influence of the LiTDI additive is worth exploring also in other battery chemistries.

Place, publisher, year, edition, pages
ELECTROCHEMICAL SOC INC, 2018
National Category
Materials Chemistry Physical Chemistry
Identifiers
urn:nbn:se:uu:diva-356819 (URN)10.1149/2.0231802jes (DOI)000431786800005 ()
Funder
Swedish Energy Agency, 34191-1
Available from: 2018-08-16 Created: 2018-08-16 Last updated: 2018-08-16Bibliographically approved
Oltean, G., Plylahan, N., Ihrfors, C., Wei, W., Xu, C., Edström, K., . . . Gustafsson, T. (2018). Towards Li-ion batteries operating at 80 °C: Ionic liquid versus conventional liquid electrolytes. Batteries, 4, 2-6, Article ID 10.3390/batteries4010002.
Open this publication in new window or tab >>Towards Li-ion batteries operating at 80 °C: Ionic liquid versus conventional liquid electrolytes
Show others...
2018 (English)In: Batteries, Vol. 4, p. 2-6, article id 10.3390/batteries4010002Article in journal (Refereed) Published
Abstract [en]

Li-ion battery (LIB) full cells comprised of TiO2-nanotube (TiO2-nt) and LiFePO4 (LFP)electrodes and either a conventional organic solvent based liquid electrolyte or an ionic liquid basedelectrolyte have been cycled at 80 °C. While the cell containing the ionic liquid based electrolyteexhibited good capacity retention and rate capability during 100 cycles, rapid capacity fading was found for the corresponding cell with the organic electrolyte. Results obtained for TiO2-nt and LFP half-cells indicate an oxidative degradation of the organic electrolyte at 80 °C. In all, ionic liquidbased electrolytes can be used to significantly improve the performance of LIBs operating at 80 °C.

Keywords
TiO2, ionic liquid, stability, elevated temperature, battery
National Category
Inorganic Chemistry
Research subject
Chemistry with specialization in Materials Chemistry; Chemistry with specialization in Inorganic Chemistry
Identifiers
urn:nbn:se:uu:diva-355542 (URN)10.3390/batteries4010002 (DOI)000435206300002 ()
Funder
Swedish Energy Agency, BatterifondenSwedish Foundation for Strategic Research , Road to Load
Available from: 2018-07-01 Created: 2018-07-01 Last updated: 2018-09-18Bibliographically approved
Liu, C., Rehnlund, D., Brant, W. R., Zhu, J., Gustafsson, T. & Younesi, R. (2017). Growth of NaO2 in Highly Efficient Na–O2 Batteries Revealed by Synchrotron In Operando X-ray Diffraction [Letter to the editor]. ACS Energy Letters, 2, 2440-2444
Open this publication in new window or tab >>Growth of NaO2 in Highly Efficient Na–O2 Batteries Revealed by Synchrotron In Operando X-ray Diffraction
Show others...
2017 (English)In: ACS Energy Letters, E-ISSN 2380-8195, Vol. 2, p. 2440-2444Article in journal, Letter (Other academic) Published
Abstract [en]

The development of Na–O2 batteries requires understanding the formation of reaction products, as different groups reported compounds such as sodium peroxide, sodium superoxide, and hydrated sodium peroxide as the main discharge products. In this study, we used in operando synchrotron radiation powder X-ray diffraction (SR-PXD) to (i) quantitatively track the formation of NaO2 in Na–O2 cells and (ii) measure how the growth of crystalline NaO2 is influenced by the choice of electrolyte salt. The results reveal that the discharge could be divided into two time regions and that the formation of NaO2 during the major part of the discharge reaction is highly efficient. The findings indicate that the cell with NaOTf salt exhibited higher capacity than the cell with NaPF6 salt, whereas the average domain size of NaO2 particles decreases during the discharge. This fundamental insight brings new information on the working mechanism of Na–O2 batteries.

National Category
Materials Chemistry
Research subject
Chemistry with specialization in Materials Chemistry
Identifiers
urn:nbn:se:uu:diva-330766 (URN)10.1021/acsenergylett.7b00768 (DOI)000415914200036 ()
Projects
Na-air batteries
Available from: 2017-10-03 Created: 2017-10-03 Last updated: 2018-02-26Bibliographically approved
Liu, J., Ma, Y., Roberts, M., Gustafsson, T., Edström, K. & Zhu, J. (2017). Highly efficient Ru/MnO2 nano-catalysts for Li-O2 batteries: Quantitative analysis of catalytic Li2O2 decomposition by operando synchrotron X-ray diffraction. Journal of Power Sources, 352, 208-215
Open this publication in new window or tab >>Highly efficient Ru/MnO2 nano-catalysts for Li-O2 batteries: Quantitative analysis of catalytic Li2O2 decomposition by operando synchrotron X-ray diffraction
Show others...
2017 (English)In: Journal of Power Sources, ISSN 0378-7753, E-ISSN 1873-2755, Vol. 352, p. 208-215Article in journal (Refereed) Published
Abstract [en]

In-situ or operando quantitative analysis is very important for Li-O2 batteries, in order to properly, accurately and comprehensively evaluate electrocatalysts and characterize Li-O2 electrochemistry in real-time. Synchrotron XRD can provide much higher X-ray intensity and time resolution than traditional in-house diffractometers, and therefore can contribute to quantitative analysis for Li-O2 batteries. Here, operando synchrotron XRD is further developed to quantitatively study Li-O2 batteries with nano catalysts, Ru/MnO2. The time-resolved oxygen evolution reaction (OER) kinetics for Li-O2 cells with Ru/MNT was systematically investigated using operando synchrotron radiation powder X-ray diffraction (SR-PXD). Li2O2 decomposition in the electrodes with Ru/MNT catalysts during galvanostatic and potentiostatic charge processes followed pseudo-zero-order kinetics and showed ideal Coulombic efficiency (close to 100%). Furthermore, it was found that the OER kinetics for a cell with 2 wt% Ru/MNT charged at a constant potential of 4.3 V was even faster than that for a cell with the same amount of pure Ru nanoparticles, which have been considered as a highly active catalyst for Li-O2 batteries. These results indicated that Ru/MNT with a special nanostructure represented a very efficient electrocatalyst for promoting the OER in Li-O2 batteries. We also demonstrate that synchrotron radiation XRD can "highlight" a way to quantitative analysis for Li-O2 batteries.

Keywords
Ru nanoparticle, MnO2 nanotube, Li-O-2 battery, Electrocatalyst, Oxygen evolution reaction, Operando synchrotron radiation powder X-ray diffraction (SR-PXD)
National Category
Materials Chemistry Other Chemical Engineering
Identifiers
urn:nbn:se:uu:diva-324237 (URN)10.1016/j.jpowsour.2017.03.127 (DOI)000401206100024 ()
Funder
Swedish Research Council, 2012-4681Swedish Energy Agency, 2010-000414StandUp
Available from: 2017-06-15 Created: 2017-06-15 Last updated: 2017-12-30
Blidberg, A., Sobkowiak, A., Tengstedt, C., Valvo, M., Gustafsson, T. & Björefors, F. (2017). Identifying the Electrochemical Processes in LiFeSO4F Cathodes for Lithium Ion Batteries. Chemelectrochem, 4(8), 1896-1907
Open this publication in new window or tab >>Identifying the Electrochemical Processes in LiFeSO4F Cathodes for Lithium Ion Batteries
Show others...
2017 (English)In: Chemelectrochem, Vol. 4, no 8, p. 1896-1907Article in journal (Other academic) Published
Abstract [en]

The electrochemical performance of tavorite LiFeSO4F can be considerably improved by coating the material with a conducting polymer (poly(3,4-ethylenedioxythiophene); PEDOT). Herein, the mechanisms behind the improved performance are studied systematically by careful electrochemical analysis. It is shown that the PEDOT coating improves the surface reaction kinetics for the Li-ion insertion into LiFeSO4F. For such coated materials no kinetic limitations remain, and a transition from solid state to solution-based diffusion control was observed at 0.6 mA cm−2 (circa C/2). Additionally, the quantity of PEDOT is optimized to balance the weight added by the polymer and the improved electrochemical function. Post mortem analysis shows excellent stability for the LiFeSO4F-PEDOT composite, and maintaining the electronic wiring is the most important factor for stable electrochemical cycling of LiFeSO4F. The insights and the methodology used to determine the rate-controlling steps are readily transferable to other ion-insertion-based electrodes, and the findings are important for the development of improved battery electrodes.

Keywords
Batteries; conducting polymers; electrochemistry; kinetics; lithium
National Category
Inorganic Chemistry
Identifiers
urn:nbn:se:uu:diva-317003 (URN)10.1002/celc.201700192 (DOI)000410498700015 ()
Funder
Swedish Foundation for Strategic Research , EM11-0028VINNOVASwedish Research Council Formas, 245-2014-668
Available from: 2017-03-08 Created: 2017-03-08 Last updated: 2017-12-08Bibliographically approved
Liu, C., Carboni, M., Brant, W. R., Pan, R., Hedman, J., Zhu, J., . . . Younesi, R. (2017). Insights into the Stability of Discharge Products in Na-O2 Batteries.
Open this publication in new window or tab >>Insights into the Stability of Discharge Products in Na-O2 Batteries
Show others...
2017 (English)Other (Other academic)
Keywords
Materials Chemistry, Materialkemi
National Category
Materials Chemistry
Identifiers
urn:nbn:se:uu:diva-338358 (URN)
Note

2018-01-08T14:32:53.090+01:00

Available from: 2018-01-08 Created: 2018-01-08 Last updated: 2018-07-19
Xu, C., Renault, S., Ebadi, M., Wang, Z., Björklund, E., Guyomard, D., . . . Gustafsson, T. (2017). LiTDI: A Highly Efficient Additive for Electrolyte Stabilization in Lithium-Ion Batteries. Chemistry of Materials, 29(5), 2254-2263
Open this publication in new window or tab >>LiTDI: A Highly Efficient Additive for Electrolyte Stabilization in Lithium-Ion Batteries
Show others...
2017 (English)In: Chemistry of Materials, ISSN 0897-4756, E-ISSN 1520-5002, Vol. 29, no 5, p. 2254-2263Article in journal (Refereed) Published
Abstract [en]

The poor stability of LiPF6-based electrolytes has always been a bottleneck for conventional lithium-ion batteries. The presence of inevitable trace amounts of moisture and the operation of batteries at elevated temperatures are particularly detrimental to electrolyte stability. Here, lithium 2trifluoromethy1-4,5-dicyanoimidazole (LiTDI) is investigated as a moisture-scavenging electrolyte additive and can sufficiently suppress the hydrolysis of LiPF6. With 2 wt % LiTDI, no LiPF6 degradation can be detected after storage for 35 days, even though the water level in the electrolyte is enriched by 2000 ppm. An improved thermal stability is also obtained by employing the LiTDI additive, and the moisture-scavenging mechanism is discussed. The beneficial effects of the LiTDI additive on battery performance are demonstrated by the enhanced capacity retention of both the LiNi1/3Mn1/3Co1/3O2 (NMC)/Li and NMC/graphite cells at 55 degrees C. In particular, the increase in cell voltage hysteresis is greatly hindered when LiTDI is presented in the electrolyte. Further development of the LiTDI additive may allow the improvement of elevated-temperature batteries, as well as energy savings by reducing the amount of effort necessary for dehydration of battery components.

Place, publisher, year, edition, pages
AMER CHEMICAL SOC, 2017
National Category
Physical Chemistry
Identifiers
urn:nbn:se:uu:diva-319530 (URN)10.1021/acs.chemmater.6b05247 (DOI)000396639400040 ()
Funder
Swedish Energy Agency, 34191-1 39036-1Swedish Foundation for Strategic Research Carl Tryggers foundation StandUp
Available from: 2017-04-06 Created: 2017-04-06 Last updated: 2017-12-30
Mindemark, J., Sobkowiak, A., Oltean, G., Brandell, D. & Gustafsson, T. (2017). Mechanical Stabilization of Solid Polymer Electrolytes through Gamma Irradiation. Electrochimica Acta, 230, 189-195
Open this publication in new window or tab >>Mechanical Stabilization of Solid Polymer Electrolytes through Gamma Irradiation
Show others...
2017 (English)In: Electrochimica Acta, ISSN 0013-4686, E-ISSN 1873-3859, Vol. 230, p. 189-195Article in journal (Refereed) Published
Abstract [en]

Attaining sufficient mechanical stability is a challenge for high-performance solid polymer electrolytes, particularly at elevated temperatures. We have here characterized the viscoelastic properties of the nonpolyether host material poly(epsilon-caprolactone-co-trimethylene carbonate) with and without incorporated LiTFSI salt. While this electrolyte material performs well at room temperature, at 80 degrees C the material is prone to viscous flow. Through gamma-irradiation at a dose of 25 kGy, the material stabilizes such that it behaves as a rubbery solid even at low rates of deformation while retaining a high ionic conductivity necessary for use in solid-state Li batteries. The performance of the irradiated electrolyte was investigated in Li polymer half-cells (Li vs. LiFePO4) at both 80 degrees C and room temperature. In Contrast with the notably stable battery performance at low temperatures using the non-irradiated material, during cycling of the irradiated electrolytes detrimental instabilities were noted at both 80 degrees C and room temperature. The possible effects of both radiation damage to the electrolyte and impaired interfacial contacts due to the crosslinking indicate that a different procedure may be necessary in order to stabilize these electrolytes for use in battery cells capable of stable long-term operation.

Place, publisher, year, edition, pages
PERGAMON-ELSEVIER SCIENCE LTD, 2017
Keywords
polymer electrolytes, crosslinking, lithium batteries, mechanical properties, gamma irradiation
National Category
Chemical Sciences
Identifiers
urn:nbn:se:uu:diva-320250 (URN)10.1016/j.electacta.2017.02.008 (DOI)000395599900021 ()
Funder
Swedish Energy Agency, 37722-1Swedish Research Council, 20123837
Available from: 2017-04-19 Created: 2017-04-19 Last updated: 2017-04-19Bibliographically approved
Srivastav, S., Xu, C., Edström, K., Gustafsson, T. & Brandell, D. (2017). Modelling the morphological background to capacity fade in Si-based lithium-ion batteries. Electrochimica Acta, 258, 755-763
Open this publication in new window or tab >>Modelling the morphological background to capacity fade in Si-based lithium-ion batteries
Show others...
2017 (English)In: Electrochimica Acta, ISSN 0013-4686, E-ISSN 1873-3859, Vol. 258, p. 755-763Article in journal (Refereed) Published
Abstract [en]

Understanding the fundamental processes at the electrode/electrolyte interface during charge and discharge will aid the development of high-capacity Li-ion batteries (LIBs) with long lifetimes. Finite Element Methodology studies are here used to investigate the interplay between morphological changes and electrochemical performance in Si negative electrodes. A one-dimensional battery model including Solid Electrolyte Interphase (SEI) layer growth is constructed for porous Si electrodes in half-cells and used for simulating electrochemical impedance response during charge and discharge cycles. The computational results are then compared with experimental investigations. The SEI layer from the electrolyte decomposition products, different depending on the presence or absence of the fluoroethylene carbonate (FEC) additive, covers the electrode surface porous structure and is leading to an increasing polarization observed in the Nyquist plots during cycling. A continuous reformation of the SEI layer after each cycle can be observed, leading to consumption of Li-|. The electrolyte composition also results in a variation of electrode porosity, which affects the performance of the cell. A more stable porous network is formed when using the FEC additive, rendering a reduction in polarization due to improved Li diffusion inside the electrode composite.

Keywords
Si-electrode, Electrochemical impedance spectroscopy, Volume change, Porosity, Morphology, SEM
National Category
Materials Chemistry
Identifiers
urn:nbn:se:uu:diva-337666 (URN)10.1016/j.electacta.2017.11.124 (DOI)000418324800085 ()
Funder
EU, FP7, Seventh Framework Programme, 608575Swedish Energy AgencyStandUp
Available from: 2018-01-03 Created: 2018-01-03 Last updated: 2018-02-09Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0003-2737-4670

Search in DiVA

Show all publications