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  • 1.
    Sjödin, Martin
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Olsson, Henrik
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Strietzel, Christian
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Strömme, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Qiu, Ziwei
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Mechanisms of Self-discharge in p-doped Conducting Polymers: Implications to the construction of electrical energy storage materials with conducting polymer components2015Conference paper (Refereed)
  • 2.
    Olsson, Henrik
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Qiu, Z.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Strömme, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Sjödin, Martin
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Parallel mechanisms of polypyrrole self-discharge in aqueous media2015In: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084, Vol. 17, p. 11014-11019Article in journal (Refereed)
    Abstract [en]

    In this report we investigate the self-discharge in a positively charged polypyrrole-cellulose composite material in water solution. Rate constants for the self-discharge reaction are determined by potential step methods and their dependence on pH, temperature and applied potential are reported. Based on the results, we propose that two fundamentally different self-discharge mechanisms operate in parallel; one of faradaic origin with a rate constant increasing exponentially with applied potential and one mechanism comprising an initial reaction of the charged polymer with hydroxide ions. The second mechanism dominates at high pH as the rate constant for this reaction increases exponentially with pH whilst the faradaic reaction dominates at low pH. With this report we hope to shed light on the complex and elusive nature of self-discharge in conducting polymers to serve as guidance for the construction of electrical energy storage devices with conducting polymer components.

  • 3.
    Olsson, Henrik
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Berg, Erik Jämstorp
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Strömme, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Sjödin, Martin
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Self-discharge in positively charged polypyrrole-cellulose composite electrodes2015In: Electrochemistry communications, ISSN 1388-2481, E-ISSN 1873-1902, Vol. 50, p. 43-46Article in journal (Refereed)
    Abstract [en]

    Self-discharge is one of the most critical issues to address to allow for industrialization of conducting polymer (CP) based electric energy storage devices. The present work investigates the underlying cause of self-discharge in positively charged polypyrrole (PPy), which is one of the most frequently studied CPs for such devices. The analyzed material is a composite of PPy and cellulose from Cladophora sp. algae forming a free standing paper-like material. From the time dependence of the potential decay as well as from independent spectroelectrochemical investigations the decay was attributed to a kinetically limiting Faradaic reaction, intrinsic to the polymer, forming a reactive intermediate that irreversibly reacts with its surroundings in a kinetically non-limiting following reaction. As such, nucleophilic addition of electrolyte nudeophiles is not found to be rate-determining. These results provide insight into the self-discharge phenomenon in p-doped CPs, and information regarding the potential range in which CPs can operate with insignificant self-discharge.

  • 4.
    Olsson, Henrik
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Strömme, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Nyholm, Leif
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Inorganic Chemistry.
    Sjödin, Martin
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Activation Barriers Provide Insight into the Mechanism of Self-Discharge in Polypyrrole2014In: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 118, no 51, p. 29643-29649Article in journal (Refereed)
    Abstract [en]

    Conducting polymers are envisioned to play a significant role in the development of organic matter based electrical energy conversion and storage systems. However, successful utilization of conducting polymers relies on a fundamental understanding of their inherent possibilities and limitations. In this report we studied the temperature dependence of the self-discharge in polypyrrole and show that the rate of self-discharge is kinetically controlled by a polymer intrinsic endergonic electron transfer reaction forming a reactive intermediate. We further show that this intermediate is intimately linked to a process known as overoxidation. This process is general for most, if not all, p-doped conducting polymers irrespective of medium. The results herein are therefore expected to significantly impact the development of future energy storage systems with conducting polymer based components.

  • 5.
    Olsson, Henrik
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Tammela, Petter
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Wang, Zhaoui
    Carlsson, Daniel O.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Sjödin, Martin
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Mihranyan, Albert
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Strömme, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Nyholm, Leif
    Energy Storage with Nanocellulose and Polypyrrole2014In: 1st International Symposium on Energy Challenges and Mechanics, 2014Conference paper (Refereed)
  • 6.
    Tammela, Petter
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Olsson, Henrik
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Wang, Zhaohui
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Inorganic Chemistry.
    Strømme, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Nyholm, Leif
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Inorganic Chemistry.
    Influence of Separator and Electrode Thickness on Cell Resistance in Energy Storage Devices based on Polypyrrole-Cellulose Composites2014In: GradSAM21 workshop 2014: Graduate School of Advanced Materials for the 21st Century, 2014Conference paper (Other academic)
    Abstract [en]

    The next-generation electronic industry requires access to inexpensive, flexible, light-weight and environmentally friendly energy storage devices [1]. Consequently, a lot of research has been directed toward producing versatile and flexible materials as a complement to the materials used in contemporary batteries and supercapacitors. Electroactive polymers represent an attractive alternative and electronically conducting polymers have hence received considerable interest as it is well-known that these materials can be used to manufacture all-polymer-based batteries and supercapacitors [2]. The performance of such energy storage devices is, however, ultimately limited by the resistance of the cell [3]. One important aspect is therefore to consider the cell resistance when optimizing the performance and cell design.

    Our recent activities have shown that a flexible and highly porous cellulose and polypyrrole composite, obtained by polymerizing pyrrole on cellulose from the Cladophora sp. algae, can be used as paper-based electrode materials and together with an aqueous salt solution form an environmentally friendly charge storage device [4, 5]. The cellulose-polypyrrole-based device proved to cycle for thousands of cycles without significant loss of capacity even at high charge and discharge rates.

    In the present work, the cell resistances of cellulose-polypyrrole-based charge storage devices are investigated, and the influence of electrode material and separator thickness are examined. The effect of absorption of electrolyte in the separator compared to bulk solutions of electrolyte, and the contact resistances between current collectors and the composite are discussed, as well as the possibilities of designing inexpensive all-organic energy storage devices with promising performance regarding cycling stability, rate capability and cell resistance.

  • 7.
    Tammela, Petter
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Olsson, Henrik
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Wang, Zhaohui
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Inorganic Chemistry.
    Strømme, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Nyholm, Leif
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Inorganic Chemistry.
    Influence of Separator and Electrode Thickness on Cell Resistance in Energy Storage Devices based on Polypyrrole-Cellulose Composites2014In: MRS Spring meeting April 21-25, 2014 - San Francisco, California, 2014Conference paper (Other academic)
    Abstract [en]

    At present there is a strong need for the development of inexpensive, flexible, light-weight and environmentally friendly energy storage devices [1]. In this process, research is carried out to develop new versatile and flexible electrode materials as a complement to the materials used in contemporary batteries and supercapacitors. These activities have resulted in an increased interest in electronically conducting polymers (e.g. polyaniline, polypyrrole, and polythiophene) as it is known since more than two decades [2, 3] that these materials can be used to manufacture all-polymer-based batteries and supercapacitors. However, the latter devices generally suffer from problems due to low capacities, slow charging rates, poor cycling stabilities and high self-discharge rates [2]. Possible approaches to circumvent at least some of these problems involve the use of conducting polymers with carbon nanotubes [4] or cellulose [5].

    We have recently shown [5], that flexible composites, made of cellulose and polypyrrole, by chemical polymerization of pyrrole on a cellulose substrate derived from the Cladophora sp. algae, can be used as paper-based electrode materials for environmental friendly charge storage devices. The device, which has been referred to as the “Salt and Paper Battery” [6], was found to exhibit good cycling stability even at high charging and discharging rates. The latter results open up to exciting possibilities for the development of green and foldable devices as well as for a range of new applications, incompatible with conventional batteries and supercapacitors.

    The poster will focus on the results of our recent and ongoing research concerning polypyrrole and cellulose composite charge storage devices. It will be shown how the total cell resistances in the devices are influenced by thickness of the polypyrrole and cellulose composite, the thickness of the separator, and additives in the composite. Furthermore, the influence of the porosity of the separator, and the contact resistances between current collectors and the composite will be briefly discussed. It will be shown that a cheap all organic energy storage device can be assembled with promising performance.

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  • 8.
    Olsson, Henrik
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Nanocomposites of Cellulose and Conducting Polymer for Electrical Energy Storage2014Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The world’s increased energy storage demand, as well as the environmental concerns related to the combustion of fossil fuels, has triggered a transition to intermittent renewable energy sources as well as to electrical and hybrid vehicles. Current day rechargeable batteries are, due to the invention and development of lithium ion batteries, technologically well positioned to answer to some of these demands. Conventional batteries, however, utilize inorganic materials of limited supply that require large amounts of energy during refining and processing. The materials also add a significant cost to the final product, making the rechargeable batteries less attractive for large scale applications. During the last decade, significant efforts have been made to find suitable organic matter based electrode materials that can replace the inorganic materials. One class of organic materials that can be used for electrical energy storage, or be included as components in organic matter based energy storage systems, is conducting polymers.

    The aim of this thesis was to investigate the possibilities and limitations of using the conducting polymer polypyrrole in energy storage applications. The polymer was synthesized onto cellulose extracted from the Cladophora sp. algae, and the result was a flexible composite material. Symmetrical energy storage devices constructed with the composite material were shown to exhibit a pseudocapacitive behavior. The resistance in the cells was investigated and was found to scale linearly with the separator thickness. Cells could be cycled for 4,000 cycles without significant capacitance loss and cells that were overcharged to 1.8 V cell potential, were found to be protected by a resistive potential drop. Devices were constructed as proof-of-concept and were used to power a remote control and a digital thermometer.

    The self-discharge in polypyrrole was studied extensively. It was found that oxygen was responsible for the oxidation of the reduced electrode, while the positive electrode self-discharged due to a faradaic reaction. Through spectroscopy and the temperature dependence of the self-discharge, it was suggested that the self-discharge of oxidized polypyrrole is linked to the degradation at high potentials, commonly referred to as overoxidation.

    List of papers
    1. Cycling stability and self-protective properties of a paper-based polypyrrole energy storage device
    Open this publication in new window or tab >>Cycling stability and self-protective properties of a paper-based polypyrrole energy storage device
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    2011 (English)In: Electrochemistry communications, ISSN 1388-2481, E-ISSN 1873-1902, Vol. 13, no 8, p. 869-871Article in journal (Refereed) Published
    Abstract [en]

    A composite consisting of polypyrrole and cellulose from the Cladophora sp. green algae is shown to exhibit excellent cycling stability when used as the electrodes in an aqueous symmetric supercapacitor device. The capacitance of the device, which was 32.4 F g− 1, only decreased by 0.7% during 4000 galvanostatic cycles employing a current of 10 mA and potential cut-off limits of 0 and 0.8 V. No change in the electrode material's morphology could be seen when comparing cycled and pristine materials with scanning electron microscopy. Furthermore, no significant loss in capacitance was observed even when charging the device to 1.8 V. Measurements of the electrode potentials versus a common reference show that this effect was due to a device intrinsic self-protective mechanism which prevented degradation of the polypyrrole.

    Keywords
    Conducting polymer, Polypyrrole, Cycling stability, Composite, Cellulose
    National Category
    Natural Sciences Inorganic Chemistry Engineering and Technology
    Research subject
    Engineering Science with specialization in Nanotechnology and Functional Materials; Chemistry with specialization in Inorganic Chemistry
    Identifiers
    urn:nbn:se:uu:diva-156540 (URN)10.1016/j.elecom.2011.05.024 (DOI)000294582300032 ()
    Available from: 2011-08-01 Created: 2011-08-01 Last updated: 2022-01-28Bibliographically approved
    2. Influence of the cellulose substrate on the electrochemical properties of paper-based polypyrrole electrode materials
    Open this publication in new window or tab >>Influence of the cellulose substrate on the electrochemical properties of paper-based polypyrrole electrode materials
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    2012 (English)In: Journal of Materials Science, ISSN 0022-2461, E-ISSN 1573-4803, Vol. 47, no 13, p. 5317-5325Article in journal (Refereed) Published
    Abstract [en]

    The influence of the cellulose substrate on the electrochemical performance of supercapacitor electrode materials made of polypyrrole (PPy) and cellulose is investigated. Composites were synthesized by chemical polymerization of pyrrole on dispersed fibers of cellulose from Cladophora algae and dispersed wood cellulose-based commercial filter papers, respectively, as well as on Cladophora cellulose and filter paper sheets. The resulting composites, which were characterized using scanning electron microscopy, cyclic voltammetry, and elemental analysis, were found to exhibit specific charge capacities proportional to the PPy content of the composites. The highest specific capacity (i.e., 171 C/g composite or 274 C/g PPy) was obtained for composites made from dispersed Cladophora cellulose fibers. The higher specific capacities for the Cladophora cellulose composites can be explained by the fact that the Cladophora cellulose fibers were significantly thinner than the wood cellulose fibers. While the PPy was mainly situated on the surface of the Cladophora cellulose fibers, a significant part of the PPy was found to be present within the wood fibers of the filter paper-based composites. The latter can be ascribed to a higher accessibility of the aqueous pyrrole solution to the wood-based fibers as compared to the highly crystalline algae based cellulose fibers. The present results clearly show that the choice of the cellulose substrate is important when designing electrode materials for inexpensive, flexible and environmentally friendly paper-based energy storage devices.

    National Category
    Composite Science and Engineering
    Research subject
    Engineering Science with specialization in Nanotechnology and Functional Materials
    Identifiers
    urn:nbn:se:uu:diva-174034 (URN)10.1007/s10853-012-6418-y (DOI)000302698400028 ()
    Available from: 2012-05-10 Created: 2012-05-10 Last updated: 2017-12-07
    3. Self-discharge in an electric energy storage device based on polypyrrole-cellulose composite electrodes
    Open this publication in new window or tab >>Self-discharge in an electric energy storage device based on polypyrrole-cellulose composite electrodes
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    (English)Manuscript (preprint) (Other academic)
    National Category
    Nano Technology
    Identifiers
    urn:nbn:se:uu:diva-218814 (URN)
    Available from: 2014-02-18 Created: 2014-02-18 Last updated: 2014-12-15
    4. Temperature dependence of the self-discharge in polypyrrole-cellulose composite electrodes
    Open this publication in new window or tab >>Temperature dependence of the self-discharge in polypyrrole-cellulose composite electrodes
    (English)Manuscript (preprint) (Other academic)
    National Category
    Nano Technology
    Identifiers
    urn:nbn:se:uu:diva-218813 (URN)
    Available from: 2014-02-18 Created: 2014-02-18 Last updated: 2014-12-15
    5. The influence of electrode and separator thickness on the cell resistance of symmetric cellulose–polypyrrole-based electric energy storage devices
    Open this publication in new window or tab >>The influence of electrode and separator thickness on the cell resistance of symmetric cellulose–polypyrrole-based electric energy storage devices
    2014 (English)In: Journal of Power Sources, ISSN 0378-7753, E-ISSN 1873-2755, Vol. 272, p. 468-475Article in journal (Refereed) Published
    Abstract [en]

    The influence of the cell design of symmetric polypyrrole and cellulose-based electric energy storage devices on the cell resistance was investigated using chronopotentiometric and ac impedance measurements with different separator and electrode thicknesses. The cell resistance was found to be dominated by the electrolyte and current collector resistances while the contribution from the composite electrode material was negligible. Due to the electrolyte within the porous electrodes thin separators could be used in combination with thick composite electrodes without loss of performance. The paper separator contributed with a resistance of similar to 1.5 Omega mm(-1) in a 1.0 M NaNO3 electrolyte and the tortuosity value for the separator was about 2.5. The contribution from the graphite foil current collectors was about similar to 0.4-1.1 Omega and this contribution could not be reduced by using platinum foil current collectors due to larger contact resistances. The introduction of chopped carbon fibres into the electrode material or the application of pressure across the cells, however, decreased the charge transfer resistance significantly. As the present results demonstrate that cells with higher charge storage capacities but with the same cell resistance can be obtained by increasing the electrode thickness, the development of paper based energy storage devices is facilitated.

    National Category
    Nano Technology
    Identifiers
    urn:nbn:se:uu:diva-218812 (URN)10.1016/j.jpowsour.2014.08.041 (DOI)000344208700058 ()
    Available from: 2014-02-18 Created: 2014-02-18 Last updated: 2022-01-28Bibliographically approved
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  • 9.
    Sjödin, Martin
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Karlsson, Christoffer
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Huang, Hao
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Olsson, Henrik
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Yang, Li
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Gogoll, Adolf
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - BMC, Synthetical Organic Chemistry.
    Nyholm, Leif
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Inorganic Chemistry.
    Strömme, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Organic Battery Materials based on Conducting Polymer Backbones with High Capacity Pending Groups2014Conference paper (Refereed)
    Abstract [en]

    Organic matter based battery materials have attracted large interest due to their inherent ability to provide an environmentally benign alternative to inorganic batteries because such materials can be produced from renewable resources via eco-efficient processes. The development of organic battery materials rely on several key factors that need to be resolved, the most important being dissolution problems, limited electronic conductivity, degradation of active material and slow redox kinetics. Conducting polymers are insoluble in most electrolytes, they are electronically conducting and show fast redox conversion but are, to some extent, unstable and have insufficient charge capacities for battery applications.

                To understand the instability of conducting polymers we have measured self discharge rates in polypyrrole at different temperatures. From these experiments it is clear that the self-discharge originates from an activated redox reaction with an activation barrier of around 0.4 eV. Although the exact nature of the redox reaction has not been identified we have been able to link the self discharge to, what is commonly referred to as, over-oxidation. Over-oxidation is common to polyacetylene, polyparaphenylene, polypyrrole and polythiophene and this mechanism of self discharge is thus a general feature of conducting polymers. This self-discharge mechanism is suppressed by low polymer doping levels, low potentials and low temperatures.     

    By attaching high capacity redox active groups onto the conducting polymer backbone the charge capacity can be increased while retaining electronic conductivity and insolubility. We have attached quinone groups to each repeat unit of polypyrrole for this purpose. Interestingly, in-situ spectroscopic measurements show that during quinone redox conversion the polymer doping level is in-fact reduced. Since the doping level of the polymer affects the rate of self-discharge the attachment of quinone units to the polypyrrole chain not only increases the charge capacity but also provides a conceptual strategy to control self discharge. 

  • 10.
    Olsson, Henrik
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Karlsson, Christoffer
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Strømme, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Sjödin, Martin
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Nyholm, Leif
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Inorganic Chemistry.
    Study of the Self-Discharge Mechanism in Polypyrrole2014Conference paper (Other (popular science, discussion, etc.))
  • 11.
    Sjödin, Martin
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Karlsson, Christoffer
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Tammela, Petter
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Huang, Hao
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Yang, Li
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Olsson, Henrik
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Huang, Xiao
    Sustainable Batteries2014In: NFM conference, Prague 16-18th June 2014., 2014Conference paper (Other academic)
  • 12.
    Tammela, Petter
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Olsson, Henrik
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Strømme, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Nyholm, Leif
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Inorganic Chemistry.
    The influence of electrode and separator thickness on the cell resistance of symmetric cellulose–polypyrrole-based electric energy storage devices2014In: Journal of Power Sources, ISSN 0378-7753, E-ISSN 1873-2755, Vol. 272, p. 468-475Article in journal (Refereed)
    Abstract [en]

    The influence of the cell design of symmetric polypyrrole and cellulose-based electric energy storage devices on the cell resistance was investigated using chronopotentiometric and ac impedance measurements with different separator and electrode thicknesses. The cell resistance was found to be dominated by the electrolyte and current collector resistances while the contribution from the composite electrode material was negligible. Due to the electrolyte within the porous electrodes thin separators could be used in combination with thick composite electrodes without loss of performance. The paper separator contributed with a resistance of similar to 1.5 Omega mm(-1) in a 1.0 M NaNO3 electrolyte and the tortuosity value for the separator was about 2.5. The contribution from the graphite foil current collectors was about similar to 0.4-1.1 Omega and this contribution could not be reduced by using platinum foil current collectors due to larger contact resistances. The introduction of chopped carbon fibres into the electrode material or the application of pressure across the cells, however, decreased the charge transfer resistance significantly. As the present results demonstrate that cells with higher charge storage capacities but with the same cell resistance can be obtained by increasing the electrode thickness, the development of paper based energy storage devices is facilitated.

  • 13.
    Karlsson, Christoffer
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Olsson, Henrik
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Sjödin, Martin
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Electric Energy Storage: Conducting Redox Polymers2013Conference paper (Refereed)
  • 14.
    Karlsson, Christoffer
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Huang, Hao
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Olsson, Henrik
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Strømme, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Gogoll, Adolf
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - BMC, Synthetical Organic Chemistry.
    Sjödin, Martin
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Kinetics of conducting polymers with side chain quinone units2013Conference paper (Refereed)
    Abstract [en]

    Quinones have been suggested as active material in organic lithium ion battery (LIB) cathodes. They are expected to have higher specific capacities and to be cheaper and more environmentally friendly than the inorganic lithium intercalation compounds used in LIBs today. However, quinone compounds suggested for this purpose often suffer from slow kinetics and low cyclability due to dissolution. In this work, conducting polymers containing pending quinone moieties were synthesized. Immobilizing the redox active quinone units on a conducting polymer matrix decreases both resistance and solubility, which improves the speed and the cyclability of the system, while maintaining a high specific capacity. The two-electron redox reaction of the quinone units in these polymers yields a theoretical capacity of ~300 mAh/g. The polymers were studied electrochemically and spectroscopically to elucidate the kinetics of the polymer charging and the redox cycling of the quinone units.

  • 15.
    Olsson, Henrik
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Karlsson, Christoffer
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Sjödin, Martin
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Strømme, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Nyholm, Leif
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Inorganic Chemistry.
    Organic Energy Storage: The Algae Battery2013Conference paper (Other academic)
  • 16.
    Karlsson, Christoffer
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Huang, Hao
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Olsson, Henrik
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Strømme, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Gogoll, Adolf
    Sjödin, Martin
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Poly(pyrrol-3-ylhydroquinone) – A Conducting Redox Polymer for Electric Energy Storage2013Conference paper (Refereed)
  • 17.
    Karlsson, Christoffer
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Huang, Hao
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Olsson, Henrik
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Strømme, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Gogoll, Adolf
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - BMC.
    Sjödin, Martin
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Poly(pyrrol-3-ylhydroquinone) – A Conducting Redox Polymer for Electric Energy Storage2013Conference paper (Refereed)
  • 18.
    Olsson, Henrik
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Karlsson, Christoffer
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Nyholm, Leif
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Inorganic Chemistry.
    Strømme, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Sjödin, Martin
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Study of the Self-Discharge Mechanism in Polypyrrole2013Conference paper (Other academic)
  • 19.
    Tammela, Petter
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Olsson, Henrik
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Wang, Zhao-hui
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Inorganic Chemistry.
    Sjödin, Martin
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Strömme, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Nyholm, Leif
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Inorganic Chemistry.
    The Influence Of The Separator And Electrode Thickness On The Cell Resistance For Energy Storage Devices Based On Polypyrrole-Cellulose Composites 2013In: Nordbatt1 2013, 2013, p. P52-Conference paper (Refereed)
  • 20.
    Olsson, Henrik
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.