This is a collection of poster abstracts at Nordbatt2019. We have also made an overview of the poster titles and authors.
This year we will have two poster prizes. The Best Poster-award winner is selected by members of the scientific committee and the Crowd Favorite-award winner is selected by all conference participants.
Info to poster presenters: The recommended poster format is A0 (84.1 cm x 118.9 cm) in portrait orientation. It is also possible to fit A0 in landscape orientation to the poster boards (130 cm x 160 cm).“
|1||Rapid cycling of Li-ion cells for cold climates |
Alexander Smith, Royal Institute of Technology, KTH
ABSTRACT: To ensure electric vehicles as a convenient and viable transportation solution, battery lifetime must be improved by better understanding the conditions and signs of aging. Power-optimized cylindrical NMC-LMO/graphite Li-ion cells were cycled in sub-ambient and room temperatures at 1C and 3C rates over the full SOC range (0-100%). Conditions were selected to investigate aging in cold climates with increased risk for Li plating. Differential voltage analysis, differential thermal voltammetry, and electrochemical impedance spectroscopy were conducted in situ to study degradation. Ambient cycling at 1C rate caused the earliest end-of-life (80% remaining capacity) after 2500 equivalent cycles. At 3C rate and 10°C, cells lasted longer; slower late-life degradation contributed to a lifespan of >3500 equivalent cycles. In all cases, loss of cyclable lithium was the dominant mode of capacity fade, confirmed by dV/dQ. Ongoing post mortem analysis will elucidate specific aging mechanisms.
|2||Amorphous iron phosphate thin films in Li-ion batteries |
Anders Brennhagen, University of Oslo
ABSTRACT: In this work, we have investigated amorphous thin films of Fe4(P2O7)3 and FePO4 as cathode materials in Li-ion batteries. The materials show very high power capabilities and good stability.
|3||The ACES (Across Continents Electric Vehicle Services) project |
Andreas Thingvad, DTU Elektro, Technical University of Denmark
ABSTRACT: The ACES project holistically investigate technical and economic system benefits and impacts by large scale electric vehicles integration in Bornholm, augmented by real usage patterns, grid data and field testing for across continents replicability. A full scale penetration scenario of electrical vehicles at Bornholm is simulated in order to assess how new aggregating functionalities – both technically and economically – can support a successful integration of electric vehicles into the energy system.
|4||A new operando cell for neutron diffraction on Li-ion battery materials |
Andreas Østergaar Drejer, University of Southern Denmark
ABSTRACT: The use of operando diffraction has taken a major step forward, in no small part due to the increase in flux at large scale facilities such as synchrotrons and neutron spallation sources. While X-rays are absorbed by typical battery casings, which necessitates special designed cells, neutrons have a penetration depth large enough to probe the entirety of a battery cell. This has allowed measurements directly on commercial batteries, giving unique insights into the evolution of cell parameters and composition of the cathode and anode phase, but also showing Li-consumption by decomposition of the electrolyte and plating of lithium metal. In this work, we develop a new operando neutron diffraction battery cell, which allows easy measurement on a variety of different non-commercial cathode materials. The cell uses a Zr/Ti-alloy with negligible scattering strength to eliminate contributions from the casing. We present data on from the cell on the electrode materials LiFePO4 and LiVPO4F.
|5||Enabling All-Carbon Dual-ion Batteries through Highly Concentrated Electrolytes |
Antonia Kotronia, Uppsala University
ABSTRACT: Dual-ion batteries (DIBs) rely on the redox amphotericity of graphite which allows for intercalation of cations and anions into its structure. Exploiting this, high-voltage (above 4.7 V vs. lithium) rechargeable batteries can be developed without using any transition metal-containing active materials. This cheap, safe and environmentally-friendly technology needs, however, to overcome considerable challenges before commercialization. Most importantly, the development of DIBs is affected by capacity fading associated with graphite exfoliation upon anion intercalation and the lack of current collectors that can withstand corrosion at high operational voltages. This study attempts to tackle both issues by employing highly concentrated electrolytes with PF6-, TFSI- and FSI- anions. The impact of anion intercalation on the structure of graphite and the oxidative stability of Al current collectors in concentrated electrolytes are studied using electrochemical and spectroscopic techniques.
|6||Autonomous optimization of second use battery storage systems |
Bernhard Fäßler, University of Agder
ABSTRACT: Electric vehicles are becoming more and more popular. This trend does not only rely on governmental incentives, it is also due to technology development leading to increased driving range and lower battery costs, driven by ever increasing environmental concerns. Unfortunately, electric vehicle batteries lose usable capacity over time and usage and are normally replaced when they reach 80% if their initial capacity. In parallel, the share of intermittent renewable sources, such as wind and solar, is growing rapidly which affects grid stability and power quality. Buffer storages are needed to compensate for imbalances between energy demand and generation where second use batteries could be a viable alternative to traditional solutions such as pumped storage hydro power plants. The University of Agder is working, among other battery related research, on stationary, second use storage assembly possibilities and application dependent controllers to allow for autonomous storage operation.
|7||The structural and electronic properties of anti-fluorite Li2X (X = S and Te) compounds |
Brahim Bahloul, Ecole Normale Supérieure de Bou-Saada
ABSTRACT: The structural and electronic properties of anti-fluorite Li2X (X=S and Te) compounds were investigated using the density functional theory. The exchange-correlation potential is treated by the generalized gradient approximation (GGA) of Perdew-Burke-Ernzerhof (PBE) and the local density approximation (LDA) of Teter–Pade (TP). Our calculated lattice parameters at equilibrium volume are in good agreement with available experimental data and other theoretical calculations. The electronic band structures and density of states were obtained. The anti-fluorite Li2S and Li2Te present an indirect band gap of 3.388 eV and 2.493 eV at equilibrium. The top of the valence bands reflects the p electronic character for both structures.
|8||Disordered MnOx Li-ion Cathode Through One Step Synthesis |
Christian Lund Jakobsen, University of Southern Denmark
ABSTRACT: Layered LiMO2 (M = Co, Mn, Ni, Fe etc.), especially LiNixMnyCozO2 (LNMCO) are still among the most exploited electrode materials for commercial rechargeable Li-ion batteries. Unfortunately, they suffer from high cost and toxicity due to Co as well as poor thermal stability due to Ni. To overcome these issues, Mn-based oxide materials are receiving significant attention during the last decade due to the low cost and toxicity of Mn and the discovery of manganese oxides with specific capacities above 250 mAh/g. In this work, a disordered ramsdellite-like MnOx have been synthesized using low-temperature hydrothermal synthesis. Surprisingly, the disordered material exhibits good electrochemical performance as Li-ion cathode as opposed to a crystalline manganese phosphate obtained from similar synthesis. We have investigated the structural and compositional details about the disordered phase as well as insight into the Li-ion intercalation mechanism.
|9||The formation of electrode-electrolyte interphases in polyester-based solid polymer electrolytes for solid-state LIBs |
Christofer Sångeland, Uppsala University
ABSTRACT: The efficiency and lifetime of lithium-ion batteries is largely dependent on the formation of stable and highly ion-conductive electrode-electrolyte interphases. It has been shown that incorporating a flexible poly(caprolactone) (PCL) moiety in poly(trimethylene carbonate)-based solid polymer electrolyte (SPE) is beneficial in terms of ionic conductivity, however, the effect of PCL on the electrode-electrolyte interphase has yet to be investigated. In this work, the Electrochemical Stability Window and formation of interfacial resistances in the PCL-LiTFSI-based SPE was studied using EIS at different potentials. Using post mortem XPS, we hope to identify compositional changes in the interface which are responsible for changes in frequency-impedance response. In order to facilitate separation of the layers for post mortem XPS analysis, we have synthesized a high molecular weight PCL and opted for lower salt concentrations to obtain a material which is less adhesive.
|10||Performance of Si anodes in ionic liquid electrolytes with added carbonates |
Daniel Tevik Rogstad, Norwegian University of Science and Technology
ABSTRACT: Electrolytes consisting of the lithium bis(fluorosulfonyl)imide (LiFSI) salt and the room temperature ionic liquid N-Propyl-N-methylpyrrolidinium bis(fluorosulfonyl)imide (PYR13FSI) were made with and without the addition of dimethyl carbonate (DMC) and fluoroethylene carbonate (FEC). EL-CELL PAT-cells were assembled using a 73 wt% µ-Si electrode in pseudo full cell setup with a capacitively oversized LiFePO4 cathode to determine the effect of the electrolytes on rate performance and cycling stability. Silicon electrodes were extracted from cells cycled 1, 11 and 51 cycles and the composition and growth of the SEI layer was analyzed using XPS. It is shown that mixing small amounts of carbonate into ionic liquid electrolytes can have a positive effect on the rate capability of silicon electrodes in Li-ion batteries as compared to electrolytes of pure ionic liquids. The addition of FEC in addition to DMC seems to be essential to also retain a good cycling stability.
|11||Surface coated LiNi0.5Mn1.5O4 as a high-voltage cathode material for Li-ion batteries |
Elise Ramleth Østli, Norwegian University of Science and Technology
ABSTRACT: LiNi0.5Mn1.5O4 (LNMO) is a promising cathode material for Li-ion batteries (LIBs) due to its high operating voltage, and its environmental and economic advantages compared to other cathode materials. Commercialization of LNMO is however hindered by the unstable cathode/electrolyte interface that leads to transition metal ion dissolution and a reduced battery life. The stabilizing effect of protective surface coatings, such as Al2O3, TiO2, and ZnO, have previously been reported. However, several of these studies have performed electrochemical characterization in half-cell configuration, thus losing important information of degradation effects that can be hidden by the unlimited Li supply. In this study, we investigate LNMO coated with TiO2 by atomic layer deposition (ALD). We perform electrochemical characterization in full-cell configuration with a graphite anode and, combined with post-mortem analysis, we determine the stabilizing effect of TiO2 on the cathode/electrolyte interface.
|12||Ageing and safety aspects of commercial marine Li-ion batteries at low temperatures |
Embla Tharaldsen Bø, Institute for Energy Technology, IFE
ABSTRACT: Degradation and ageing of Li-ion batteries will contribute to reduced thermal stability which potentially affects safety performance of the batteries. The fact that aging of lithium-ion cells leads to a reduced capacity and cell life, is extensively covered in the literature by several research groups. The safety effects of ageing are far less studied, with only a handful of empirical studies published. This poster presents ageing data and safety aspects of large commercial Li-ion cells aged and cycled at 5, 25 and 45°C. Several diagnostic tools have been applied to characterise the ageing mechanisms. Ageing mechanisms are different at low and high temperatures affecting the thermal stability of the aged cells. The thermal stability of cells which have been aged with different ageing mechanisms was characterized with an ARC. It was observed that a cell cycled at 5°C for 3000 cycles reaching 70% SoH showed a reduced thermal runaway limit from 240 to 150°C compared to uncycled cells.
|13||Na-dynamics in NZTO, a possible solid-state electrolyte |
Frida Sveen Hempel, University of Oslo and SINTEF
ABSTRACT: Improving a specific material property requires a thorough understanding of its limiting factors. To compete with the existing liquid electrolytes, solid state electrolytes require materials with an exceptional ion conductivity. Layered hexagonal P2-type materials have been investigated as candidates for both cathode and electrolyte of solid-state batteries. To thoroughly understand the sodium dynamics, nuclear magnetic resistance (NMR) is employed. It probes the local environment of each Na-position in the electrolyte candidate material Na3Zn2SbO6, at different temperatures. The preliminary results show the transition of one position from inactive to active in the Na conduction, making this a probable limiting factor of ion conduction in this material. These results also display the strength of NMR as a tool to understand Na-dynamics.
|14||Investigating the Mg ion Intercalation Properties of MXenes |
Frode Håskjold Fagerli, Norwegian University of Science and Technology
ABSTRACT: Two-dimensional MXenes have shown promising theoretical properties for rechargeable magnesium battery (RMB) cathodes. Here, we present a systematic investigation of the Mg2+ intercalating properties of two different multi-layered MXenes, Ti3C2 and V2C, utilizing the standard APC:THF electrolyte, and cycled at various temperatures. The cycling results show poor capacities, even at elevated temperatures (60°C), indicating that no significant intercalation occurs. DFT calculations of the migration barriers and intercalation energies of these MXenes, with various surface terminations, resulted in a trade-off between very high migration barriers for the movement of Mg2+ in the MXenes, or a positive intercalation energy. These preliminary results give useful insight of the cathodic performances of MXenes in RMBs.
|15||Garnet-Polyester Composite Electrolyte for Solid-State Li-ion Batteries |
Funeka Nkosi, Uppsala University
ABSTRACT: Garnet Li7La3Zr2O12 (LLZO) constitutes one of the most promising solid-state electrolytes for all-solid-state Li-ion batteries. This is due to its attractive properties such as good ionic conductivity, excellent stability against Li-metal anode, and a wide electrochemical window of operation. However, the use of ceramic electrolytes in all-solid-state batteries remains a challenge. This is because the hard, brittle and rigid nature of ceramic electrolytes results in high interfacial resistance and the formation of cracks that favor dendrite formation and short circuits in the batteries. To address these challenges, a polyester co-polymer is incorporated in the garnet LLZO. Polyester-based polymers are suitable for the garnet-polymer composites because they are superior to traditional poly(ethylene oxide) polymer electrolytes since they have higher cation transference numbers and better ambient-temperature ionic conductivities.
|16||Capacity fade mechanisms in LiNi0.5Mn1.5O4 based cells |
Girish Salian, Uppsala University
ABSTRACT: Due to its high operating voltage and theoretical capacity of 147 mAh/g, LiNi0.5Mn1.5O4 (LNMO) renders a high theoretical energy density of 690 Wh/kg. This is because of Ni2+/Ni4+ redox couple with a voltage plateau at 4.7 V (vs. Li/Li+). Additionally, the excellent rate capabilities of LNMO makes it ideal for high-power applications. However, due to high voltage operation, the instability of conventional electrolytes (aprotic carbonates with LiPF6 salt) causes interfacial reactions accompanied by transition metal dissolution, especially at elevated temperatures, leading to rapid capacity fading. To address the above given issues, EC (ethylene carbonate)-free electrolytes could be employed since EC based electrolytes experience poor stabilities at higher potentials. We will present our latest results on studying EC-free electrolytes for LNMO based cells. Electrochemical measurements of LNMO based cells, in which different types of counter-electrodes were used, will be discussed.
|17||High-Performance Single Crystal Ni-rich LiNi0.8Mn0.1Co0.1O2 cathode materials Enabled by an Ultrathin Surface Coating |
Haidong Liu, Uppsala University
ABSTRACT: LiNi0.8Mn0.1Co0.1O2 (NMC811), one of the most promising cathode materials to develop high energy-density lithium ion batteries, has been extensively investigated because of the high reversible capacity and lower cost. However, its practical application is hindered by the limited cycle life due to the structural instability, microcracks formation and severe electrolyte degradation at the high upper cut-off voltage. In order to overcome these issues, in this work, single crystal NMC811 materials have been successfully synthesized and further modified. The single crystalline NMC811 sample shows around 5 μm in size and polyhedral shape. Furthermore, an ultrathin surface coating (~2 nm) was built on the surface of this single crystal material. As a result, this surface-coated single crystal NMC811 material exhibited a higher reversible capacity and significant improvement of cycling stability. The capacity retention reached 86 % after 300 cycles at 0.5 C between 3 and 4.5 V vs. Li/Li+.
|18||Make Batteries Safe Again |
Halvor Høen Hval, University of Oslo
ABSTRACT: Two techniques have been used to characterize the stability of positive electrode materials under harsh conditions, more specifically at high voltage. These are implemented as the battery is cycling, in so-called operando studies. To combine information from how the structure is changing and the gas production from reactions taking place at the electrode-electrolyte interface, can provide deep knowledge about battery degrading mechanisms. The techniques used in these two approaches are Powder X-ray Diffraction (PXRD) and Mass Spectroscopy (MS), respectively. From considering the structural reversibility of the battery cycling and the set-off voltage of gas production we have a good reference value for the stability of a material.
|19||Degradation Phenomena in Silicon-Carbon Composite Anodes from Industrial Battery Grade Silicon |
Hanne Flåten Andersen, Institute for Energy Technology, IFE
ABSTRACT: Silicon as anode material has now grown to a mature field, and many degradation phenomena has been explored in detail. For current Li-ion batteries, improvement of the anode capacity beyond approximately 1200 mAh/g has negligible impact on the overall cell capacity. Thus, composite anodes containing both silicon and a conventional anode material such as graphite, are sufficient for most batteries. While degradation mechanisms of pure nano-silicon structures have been studied in detail, similar phenomena specific to composite silicon-carbon electrodes have not. In our work we have focused on understanding how different degradation phenomena evolve during cycling using post-mortem FIB-SEM and TEM studies examining the effect and interplay between the graphite and the silicon in composite anodes. This work presents results observed in silicon-carbon composites with 60 wt.% silicon prepared for degradation studies.
|20||LiNi0.8Mn0.1Co0.1O2 synthesised through an oxalic acid co-precipitation |
Harald Norrud Pollen, Norwegian University of Science and Technology
ABSTRACT: LiNi0.8Mn0.1Co0.1O2 (NMC 811) is a Ni-rich layered oxide which has received attention as a future cathode material for Li-ion batteries. The high Ni-content yields a high capacity. However, low Co- and Mn-content is detrimental to the capacity retention and the thermal stability. Surface reconstructions caused by side reactions with the electrolyte at a highly delithiated state are considered one of the main failure mechanisms. A strategy to improve both the cycle life and thermal stability is to coat the material surface, creating a physical barrier to the electrolyte. In order to achieve high capacities, the coating has to be in the low nm regime and cover the entire external surface. To enable an even coating a suitable NMC 811 baseline material with a narrow size distribution and smooth surface is needed. This work concerns NMC 811 synthesised through an oxalic acid co-precipitation. The effects of certain precipitation parameters are analysed and discussed.
|21||MXene-Sulfur Composite Cathode for Magnesium-Sulfur Batteries |
Henning Kaland, Norwegian University of Science and Technology
ABSTRACT: Mg-S batteries represent a promising approach, combining cheap, safe and abundant elements with a high theoretical energy density. The present main issue is that the soluble intermediate discharge products, Mg polysulfides, diffuse and/or migrate to the Mg anode and passivates it . A common strategy to impede the polysulfide shuttling in Li-S batteries, is to mix the sulfur with a matrix material with high polysulfide affinity, where MXenes have demonstrated promising results . In this work, Ti3C2Tx MXene has been investigated as sulfur matrix material for Mg-S batteries. Although the fabricated MXene-sulfur composite cathodes showed improved electrochemical performance compared to a carbon-based composite, the MXene-sulfur composite was still found to suffer from severe polysulfide shuttling, as evidenced by post mortem analysis.
|22||Yolk-shell-structured porous zinc vanadate at N-doped carbon anode for lithium energy storage |
Huili Cao, Technical University of Denmark
ABSTRACT: Transition metal oxides are one of the promising candidates due to its high theoretical specific capacity. However, large volume expansion of transition metal oxides during the lithiation process limits their practical application. Therefore, ensuring the electrodes’ integrity over many discharge and charge cycles is the main purpose. Here, we report a facile method to fabricate carbon coated porous zinc vanadate (Zn3V2O8@C) as anode materials. The porous structure could enhance surface electrochemical reactivity, and the existence of carbon could efficiently buffer the volume change during the lithiation/delithiation, and improves the electrical conductivity. The as-prepared Zn3V2O8@C exhibits a reversible capacity of 623 mAh g-1 after 50 cycles comparing the one without coating carbon (372 mAh g-1) at a current density of 100 mA g-1. The capacity of the carbon coated material could still remain 432 mAh g-1 at 500 mA g-1 after 250 cycles. References:  Salama et al. ACS Appl. Mater. Interfaces. 2018, 10, 36910−36917  Tang et al. Adv. Funct. Mater. 2019, 1901907
|23||Cycling of lithium batteries containing UV-crosslinked polyester-polycarbonate polymer electrolytes |
Isabell Johansson, Uppsala University
ABSTRACT: The ionic conductivity of polymer electrolytes is dependent on operational temperature, and the performance can be improved by increasing the temperature of a battery cell, however this might result in the polymer becoming softer and more prone to short-circuit. If the mechanical properties of a solid polymer electrolyte are improved the battery will exhibit better cycling performance without the risk of short-circuit, and can even safely cycle for long periods of time. The mechanical stability of a poly(caprolactone-co-trimethylenecarbonate) polymer electrolyte was improved by UV-induced crosslinking of the polymer in the presence of a photoinitiator and multifunctional acrylates. Through rheological measurements and electrochemical impedance spectroscopy, the optimal values of mechanical stability and ionic conductivity was examined to produce cells with good mechanical stability and good cycling performance, resulting in cells which can cycle at 100 °C, at rates up to 2C.
|24||How promising are Mg-batteries compared to Li-ion? |
Jacob Hadler-Jacobsen, Norwegian University of Science and Technology
ABSTRACT: Mg-batteries have been proposed as a potential future competitor to the Li-ion batteries, much due to their theoretically high volumetric charge density. However, state-of-the-art Mg-batteries has so far not been able to obtain both good cyclability and high operating voltage. In this work we have used a combination of DFT calculations and thermodynamic modelling to shed light on the fundamental promise of Mg-battery technology. Results from DFT calculations on various cathode materials will be presented, showing how migration barriers and voltages compare between Li- and Mg-ions. Ionization enthalpies and Bader charges will also be presented to explain and understand the limitations of Mg-batteries and how to best overcome them.
|25||Silicon on the Road |
Jan Petter Mæhlen, Institute for Energy Technology, IFE
ABSTRACT: IFE together with the UiO, University of Tours (France) and SINTEF recently started a new project “Silicon-on-the-Road”, with the primary aim to develop new silicon-based anode materials for lithium ion batteries. Stabilizing the surfaces of silicon particles has proven to be the most challenging step in the development of high capacity silicon-based electrodes. One of the objectives is therefore to create a material that than can coat the active particles and deliver structural integrity for the anode while keeping all the attractive properties of silicon. The project encompasses a range of coating and analyses methodologies. The current presentation will focus on results obtained using one of the more versatile methods; Atomic Layer Deposition (ALD) and our recent results on thin-film electrodes of amorphous Si as model systems for coating development. This project is co-funded by Norwegian industry and the Research Counsil of Norway through the EnergiX program.
|26||Modeling of OCV hysteresis in the NiMH battery system |
Jenny Börjesson Axén, Royal Institute of Technology, KTH
ABSTRACT: Open circuit voltage (OCV) hysteresis of batteries is a phenomenon that is rarely modeled but plays an important role in some battery systems. Hysteresis is when the properties of a material depends on the path used to attain a certain state. For batteries it depends on the charge/discharge sequence taken to reach a state of charge (SOC), and the property affected is the OCV. The NiMH battery is significantly affected by OCV hysteresis. The hysteresis window is large, a single OCV value can represent a span of SOCs as wide as 70% of the total SOC window. As a consequence, NiMH battery models without a proper description of the OCV hysteresis often render inaccurate results when simulating the behavior of systems during dynamic charge/discharge patterns. In this study different ways of modeling the OCV hysteresis is compared in a lumped model setting on different dynamic data sets from NiMH battery systems.
|27||In-operando fibre optic monitoring of lithium-ion batteries |
Jonas Hedman, Uppsala University
ABSTRACT: With the boost in electrification of vehicles, the need for reliable battery management systems (BMS) to monitor, control and predict battery performance has increased significantly. A major limitation of present BMSs is the difficulty of obtaining chemical information that describes the state of the batteries. Today, state of charge and state of health is most often estimated by externally measured temperature, current and voltage from the battery. These are insufficient tools since they do not give detailed information of battery performance during operation on an individual cell level. The use of an optical fibre sensor inserted in a cell could, however, potentially be used in batteries as an in-operando technique for measuring the state of charge and state of health in real time. In this contribution, we present the current research that has been performed by implementing optical fibre sensors and the steps taken towards understanding how batteries can be optically charac terized.
|28||LiFSI as electrolyte salt for silicon anodes and NMC cathodes |
Karina Asheim, Norwegian University of Science and Technology
ABSTRACT: Silicon is a promising high capacity anode material for Li-ion batteries. The challenge is electrode degradation and continuous solid-electrolyte interphase (SEI) growth due to volume expansion during lithiation. A stable and strong SEI is then crucial for the performance. The commercially used LiPF6 salt is susceptible to hydrolysis, forming HF which etches the SiO2 layer. An alternative salt, lithium bis(fluorosulfonyl)imide (LiFSI), has been found to improve performance of Si electrodes compared to when using LiPF6. In this work, LiFSI is evaluated as electrolyte salt for Si anode and NMC cathode in half-cell configuration. Through post mortem characterization, involving cross sectional analysis, using FIB in combination with SEM, TEM to evaluate crystallinity of particles and acquire element maps of the SEI, and XPS of the electrode surface to determine which oxidation state of elements are present, the improved performance of Si when using LiFSI is attempted explained.
|29||Post mortem analysis of stoichiometric, over-lithiated and doped LiCoO2 electrode materials for Li-ion batteries |
Katja Lahtinen, Aalto University
ABSTRACT: Lithium cobalt oxide (LiCoO2, LCO) is one of the most used materials in Li-ion batteries for portable applications. However, the consumption of Li-ion batteries is quickly increasing and as a result, the availability of the raw materials and the amount of waste batteries is increasing rapidly. Therefore, recycling of the used battery materials is an important factor to investigate. In this work, stoichiometric, over-lithiated and Mg-Ti doped LCOs prepared using the same precursors and synthesis method are aged in LCO/graphite pouch cells, and their aging behaviour is investigated and compared. The cells are then opened, the electrodes are collected, and assembled to half-cells. The LCOs are relithiated and their reuse is investigated. The results indicate that the capacity loss is caused by structural changes and loss of lithium. The Mg-Ti doped LCO withstands the changes the best because of a stabilized structure and an enhanced conductivity. Therefore it shows promising reusability.
|30||Phosphites as precursors in thin film synthesis. Using LiPO as cathode coating in Li-ion batteries |
Kristian B. Kvamme, University of Oslo
ABSTRACT: Phosphate based materials show great promise as electrolytes in solid state batteries. The ideal solid state electrolyte should be thin and uniform. For these reasons Atomic layer deposition (ALD) has been suggested as a good synthesis route for solid state electrolytes. In this work a new route for synthesising phosphorous based material using ALD is demonstrated. Phosphite precursors have been used for the synthesis of LiPO and AlPO materials. This is done by replacing phosphate precursors with phosphite precursors in established ALD synthesis routes. Furthermore the LiPO product has been deposited as a coating layer onto LiFePO4 cathodes to improve kinetics and low current density cycling performance. We have shown that there is indeed an improvement at coating thicknesses of 1 nm or less. The materials themselves have been characterised using XPS and XRF for composition analysis, and cyclic voltammetry and galvanostatic cycling for electrochemical analysis.
|31||Magnesium borohydride composites as an electrolyte for all-solid-state magnesium batteries |
Lasse Skov, Aarhus University
ABSTRACT: Solid-state electrolytes can increase the stability and safety of batteries, compared to organic solvents in existing high voltage batteries. High ionic conductivity at room temperature has been a challenge for magnesium-ion electrolytes. Mg(BH4)2 ∙ 1.6NH3 – MgO has been synthesised by our group with high ionic conductivity of between 2.2e–6 and 3.6e–3 S/cm in the temperature range of 20 to 90 degree C. This study includes a structural analysis and a theoretical explanation, based on DFT calculations, for the cation conductivity promotion observed, and a reversible electrochemical magnesium stripping/plating.
|32||Creating Automotive Renewal Project |
Lukasz Hupka, Gdansk University of Technology
ABSTRACT: Creating Automotive Renewal (CAR) project has the goal of promoting the large-scale implementation of electric mobility in the countries around the South Baltic. There are ten partners with complementary competencies and resources from Sweden, Denmark, Germany, and Poland. Project activities aim to fulfil two overall goals: 1. Implementing six pilot investments, each one of those driven by one partner. 2. Building a network of companies, public organizations, universities, research institutes, and clusters that want to contribute to the increase in systems for electric mobility.
|33||Effect of carbon coating on the electrochemical performance of SiO2-C Anodes for Li-Ion Batteries |
Maria Valeria Blanco, Norwegian University of Science and Technology
ABSTRACT: We analyzed the effect of carbon coating on the electrochemical performance of SiO2/C composites to be used as anode materials of Li-ion batteries. Composites were prepared by mixing silica nanoparticles with different amounts of glucose, sucrose and cornstarch and subjecting the resulting powders to high temperature annealing treatments at 850 degC, 1050 degC and 1200 degC. Structural, microstructural and textural differences on the composites were related to differences on the electrochemical performance of the electredes. A systematic effect of the different carbon precursors and heat treatments on the specific capacity displayed by the electrodes was observed and it allowed to identify the most suitable carbon precursor and its percentage on the composite to achieve the best electrochemical performance.
|34||Comparison of single crystal and polycrystalline lithiation for NCM622 cathode materials |
Marianna Hietaniemi, University of Oulu
ABSTRACT: Single crystal cathode active materials are commercially available, and several reports indicate them having better cycle life and better high voltage cyclability. Very few publications, however, compare single crystal material with traditional polycrystalline materials prepared from the same NCM precursor. First, electrochemical performance under different conditions is compared to see the difference between normal lithiation and single crystal lithiation. Coin cells are assembled and tested at room temperature, at elevated temperature and with high voltage cycling. They were also tested before and after washing and milling treatment. Secondly, the effect of lithiation on different precursors and their suitability for single crystal lithiation was investigated. Several NCM622 precursors were precipitated and their performance after different lithiation conditions was compared. Materials varied in particle size, particle size distribution, tap density and purity.
|35||Structural Studies of TiO2 Polymorphs as Electrode Materials in Rechargeable Batteries |
Martin Aaskov Karlsen, University of Southern Denmark
ABSTRACT: Titania has a comprehensive and diverse family of polymorphs, where differences in the connectivity of the TiO2 polyhedra give rise to channel structures with diverse channel dimensions, which is attractive for applications in intercalation-type batteries, e.g., the Li-ion battery technology. Members of the family of titania polymorphs are here studied to see how structure affects electrochemical properties. Traditionally, electrode materials for intercalation-type batteries have been crystalline. However, nanosized or disordered materials show interesting electrochemical properties as well. To probe a more local structure and limited range of order, total scattering and pair distribution function (PDF) analysis is a powerful tool. Therefore, PDF analysis is utilized in this study to explore some of the manifold titania polymorphs. X-ray total scattering and PDF analysis is used both for ex-situ studies of pristine TiO2 materials as well as for operando studies.
|36||Electronic structure of amorphous poly(ethylene oxide) |
Mikael Unge, ABB
ABSTRACT: Poly(ethylene oxide) (PEO) has been extensively studied with focus on usage as polymer electrolyte in solid state battery applications. Primarily Li ion conduction in PEO has been studied in the literature, but as the polymer electrolyte become thinner, to facilitate ion conduction, electronic leakage currents may be of increasing importance. Here we focus on electronic structure properties which will be of relevance for understanding electronic leakage currents in PEO. PEO is a semi crystalline material and here we focus on the amorphous part. Amorphous structures are generated and relaxed using molecular dynamics and electronic structure is calculated using linear-scaling DFT. First results indicate that the conduction states are inter chain states and occupies free volume pockets. Mobility edges are calculated for holes and electrons at 0 K and estimated to be 0.5 eV and 0.8 eV away from the band edges, respectively. At room temperature and 80 degC these shift to 0.1 eV and 0.3 eV, respectively.
|37||Atomic-scale Modelling of Organic Electrode Materials |
Moyses Araujo, Uppsala University
ABSTRACT: The organic electrode materials (OEM) are emerging as a promising alternative to develop greener and sustainable battery technologies. However, the poor cycling stability and low energy densities hinders their fast implementation. To overcome these hurdles, it is essential to achieve a fundamental understanding at atomic-scale of the lithiation/delithiation processes. To contribute to this end, we are developing methodologies based on evolutionary algorithms (EA) and deep neural networks (DNN) at interplay with density functional theory (DFT). They EA has been employed to predict the structure and electrochemistry of a set of dicarboxylates while the DNN has been employed in a novel machine learning approach to obtain the redox potentials. A number of learning algorithms have been investigated along with different molecular representations based (e.g. the many-body tensor representation). This study provides a framework that can aid the designing of novel organic electrode materials.
|38||The Effect of Transition Metal Counter Ion on the Super Lithiation of Benzenedipropiolate Anode Material |
Muhammad Abdelhamid, Uppsala University
ABSTRACT: Nowadays, most of energy storage solutions for mobile applications are based on Li-ion technology since its commercialisation in the early 1990s. This is due to its unsurpassed gravimetric and volumetric energy density. However, the production of Li-ion batteries (LiBs) requires large amount of non-renewable resources (e.g. inorganic ores and petroleum based materials), energy, and toxic chemicals, which raise concerns about their environmental impact and resource depletion effect. As a result, research on organic battery electrode materials for organic Li-ion batteries (OLiBs) has grown with significant results. Iron(II) benzenedipropiolate is presented and investigated as a potential negative electrode material for OLiBs. This material undergoes a reversible reduction and oxidation, first, through the iron(II) ion to iron metal, and its carbonyls. Furthermore, its unsaturated carbon–carbon bonds can be reversibly reduced and oxidized leading to a 1:1 Li:C ratio.
|39||Synthesis and performance of Nb-doped Li2ZnTi3O8 as anode material for lithium ion batteries |
Naila Firdous, DTU Energy, Technical University of Denmark
ABSTRACT: Li2ZnTi3O8 (LZTO) is recently considered as a promising anode material for lithium ion batteries (LIBs) due to its low cost and cycling stability. LZTO has lithiation voltage plateau at about 0.5 V vs Li/Li+ which avoids the formation of lithium dendrites. Its practical applications are limited due to its low conductivity and poor lithium ion diffusion coefficient. In order, to overcome its drawbacks many studies are undertaken such as doping with ions (Ni+2, Cu+2, Al+3, V+5), coating with conductive phases, altering morphology, and so on. In this study to overcome the drawbacks we had doped LZTO with appropriate amount of Nb+5 by simple solid-state synthesis. In particular, among the doped Li2-X NbxZnTi3O8 (x=0, 0.05, 0.1) materials, Li1.95 Nb0.05ZnTi3O8 showed narrow particle size distribution, uniform morphology, lower charge transfer resistance, highest discharge capacity, and good reversibility, making it more attractive as a potential anode electrode for commercialization.
|40||Operando observations of the early stages of Electrode/Electrolyte Interphase formation in Li-ion battery model systems |
Nataliia Mozhzhukhina, Uppsala University
ABSTRACT: The Electrode/Electrolyte Interphase is the vital component for successful Li-ion battery operation. Yet after several decades of research, fundamental understanding of the nature and formation mechanism of the Solid Electrolyte Interphase (SEI) remain incomplete. While the anode/electrolyte interphase has been studied intensively over the years, the cathode/electrolyte interphase has received much less attention. Although ex situ measurements were traditionally used to study the Interphase formation, the use of real time operando techniques is today mandatory in order to provide a new insight into these complex processes. We have employed Operando Surface Enhanced Raman Spectroscopy to reveal the processes occurring in the Electrical Double Layer on the gold based model systems relevant to the Li-ion batteries. Preliminary results of both anodic and cathodic electrolyte decomposition processes will be presented in the poster.
|41||Affordable porous silicon composite anode from agricultural residue |
Nathiya Kalidas, University of Eastern Finland
ABSTRACT: Silicon has been considered as the most promising high-capacity anode material for lithium-ion batteries (LIB). Si-based anode suffers from capacity loss stemming from the large volume changes (300%) during the lithiation/delitiation process. Porous silicon (PSi) structures can solve the problem and provide stable anodes for the future LIBs. The cost and environmental impact of the anode material can be reduced by using agricultural residues. Barley husk is rich in phytoliths that are amorphous nanostructures of porous silica. In the present study, PSi was prepared from barley husk ash containing nanostructured SiO2 and reduced to silicon through magnesiothermic reduction so that the nanostructure formed by the nature remains. To enhance the electrical conductivity of the PSi anode, carbon nanotubes (CNTs) were conjugated to the thermally carbonized surface of PSi particles. Due to the conjugated CNTs the rate performance of the silicon anode was essentially improved.
|42||An operando cell for dynamic X-ray diffraction with controlled stack pressure |
Olof Gustafsson, Uppsala University
ABSTRACT: Designing an operando X-ray diffraction cell can be challenging from both an electrochemical and a diffraction point of view. The cell needs to perform in a similar electrochemical manner as typical lab scale devices, such as pouch cells or coin cells. At the same time, the cell must be suitable for diffraction, i.e. give a pattern with as little contribution from background and secondary phases as possible in order to study the active material. An often overlooked parameter for operando studies of electrode materials which can impact the electrochemical performance is the stack pressure. Utilizing our own modified version of the AMPIX cell, stack pressure can easily be set with the use of an external wave spring. The cell was utilized on the P02.1 beam line at the Petra III synchrotron. Phase behaviour in the active material could be tracked accurately using X-ray diffraction, while simultaneously obtaining good electrochemical performance comparable to that seen with pouch cells.
|43||SEI formation in Li-ion batteries studied by EIS/EQCM-D |
Paul Kitz, Eidgenössische Technische Hochschule Zürich
ABSTRACT: Considering the complex dynamics of the interphase formation process in Li-ion batteries, the SEI nm-sized dimension, as well as the intermediacy and instability of many interphase species, operando analysis methods of high surface sensitivity are of interest. Operando electrochemical quartz crystal microbalance with dissipation monitoring (EQCM D) coupled with simultaneous electrochemical impedance spectroscopy (EIS) was developed for this purpose to accurately measure the mechanical and electrochemical electrode-electrolyte interphase properties. The new technique was applied to study the SEI formation process on carbon based anodes. Indeed, combined EIS/EQCM-D provides unique pieces of information for understanding the highly dynamic structure-function relationships of electrode interphases in Li-ion batteries.
|44||DFT Modelling for boosting R&D of Magnesium Technology |
Piotr Jankowski, DTU Energy, Technical University of Denmark
ABSTRACT: Magnesium battery technology is one of the promising post-lithium technology, that has potential to reduce our lithium dependence and at the same time outperform current Li-ion technology. Magnesium is more abundant, hence cheaper, and comes with promises of higher energy density and lower tendency to dendrite formation – possibility of metallic anode application. Higher safety, together with easier recycling process, in respect to lithium, give environmental friendliness and sustainability to this technology and result overall in a very attractive set of properties. Unfortunately, several challenges come along with replacement of lithium by magnesium, and need to be resolved prior to successful commercialization of this technology: low diffusion of Mg-ions inside host materials; low potential of cathode materials; aggregation of ions inside Mg-based electrolytes. Rational design of new materials is necessary and DFT calculations are shown to provide valuable support in it.
|45||Hemp-Derived Carbon as Bi-Functional Anode Material for Lithium and Sodium Ion Batteries |
Prasanna Kadirvelayutham, DTU Energy, Technical University of Denmark
ABSTRACT: Different parts of the hemp plant (Cannabis sativa) has different applications namely the seeds and flowers are used in preparing healthy foods, organic body care, and other nutraceuticals, the fibers and stalks are used in clothing, construction materials, paper, biofuel, plastic composites, and more. Similarly, in this research work, we have used hemp bast (HB) for application in energy storage devices like lithium and sodium ion batteries (LIBs and SIBs). From the HB we derived partially graphitized carbonaceous material (HBC) using simple pyrolysis process followed by washing with nitric acid. The chemical and physical properties of HBC are analysed using XRD, Raman spectroscopy, XPS, FE-SEM, and BET. The electrochemical properties of HBC are analysed using it as an anode in LIBs and SIBs. The anode electrode fabricated using HBC is found to have good cycling performance, capacity, and rate capability in both the LIBs and SIBs.
|46||Developing Li-ion conducting passivation layers on metallic lithium and their effect on electrochemistry |
Pushpaka Samarasingha, Uppsala University
ABSTRACT: Li-ion battery (LIB) demand is unprecedented at present, mainly due to an exponential growth of consumer electronics and fast development of battery-powered vehicles. Currently, the general consensus is that conventional LIBs based on liquid electrolytes have reached a saturation point for fundamental and technical developments. Hence, increasing attention is paid to performance improvements. Yet, there is still room to increase the power and energy densities of LIBs by integrating metallic lithium (Li) as advanced negative electrode. Some early attempts to use metallic Li in LIBs occurred before their commercial introduction. Nevertheless, such efforts failed due to severe safety failures. In this work, we try to develop Li-ion conducting passivation layers on metallic Li, which would be useful in addressing the safety issues posed by the highly reactive Li surface. In addition, these passivation layers could improve properties of the solid electrolyte interface (SEI) layer as well.
|47||An analytical approach to modelling of mass transfer effects in Redox Flow Batteries |
René Lorenz, DTU Energy, Technical University of Denmark
ABSTRACT: Aiming at a simple and computationally inexpensive method for analysing a single cell setup in terms of (pumping power corrected) net power, a combination of analytical models are evaluated. Regarding the fluid flow, simplification assumptions allow for relating the pressure drop to the applied flowrate with a single explicit equation, which is implemented for three configurations: Flow Through electrode, Serpentine Flow Field and Interdigitated Flow Field. Multiplying Δp with flow rate Q gives the minimum parasitic pumping loss. A first estimation of the power output is obtained by applying a Thin Film Electrode model, coupled with fluid flow by assuming a flow factor that relates stoichiometric flow rate to applied flow rate. In a second step, a differential expression of the overpotential across the electrode thickness, solved numerically, accounts for the 3D porous reaction volume. The results are compared to numerical and experimental studies.
|48||Optimisation of printed film densification for sodium nickel chloride (Na-Ni-CI) batteries |
Robert Mitchell, Center for Process Innovation, CPI
ABSTRACT: CPI are supporting LiNa Energy in development of Sodium nickel chloride (Na-Ni-CI) batteries as promising low-cost and high performance energy storage materials with potential to replace existing lithium-ion (Li-ion) batteries. CPI have used expertise and high-throughput screening facilities as well as a variety of different milling and mixing capability (e.g 3 roll mill, planetary ball mill) to develop and optimise ink formulations suitable for printing and also characterise their properties (eg stability and rheology). Screen printing methodology has been employed to support scalable production of pouch cells, with optimisation of the printed film density through ink formulation and process conditions. Structure-property relationships of the printed coatings (thickness, nano/micro-structure, etc.) have been analysed by a number of characterisation techniques including Scanning Electron Microscopy and Electrochemical Impedance Spectroscopy.
|49||Modelling Capacity Fade in Silicon Graphite Composite Electrodes |
Shweta Dhillon, Uppsala University
ABSTRACT: Silicon based anodes are highly promising candidates for Li-ion batteries, with energy densities on the cell level beyond 350 Wh/kg . Volume expansion and continuous side reactions at the silicon/electrolyte interface are, however, major obstacles that are hampering their commercialization. Current state-of-the-art anodes can present composites of graphite and Si, but with limited Si contents. We here present an electrochemical simulations based on finite element methodology to better understand the degradation mechanisms in silicon-graphite composite anodes. A 1D battery model including SEI layer growth and parasitic reactions are constructed for porous Si/graphite composite electrodes in half-cells. By simulated electrochemical impedance spectroscopy responses during charge and discharge cycles, insights into morphological changes are obtained. These computational results are supported by experimental investigations.
|50||Strategies targeting 5V Li-ion batteries |
Sidsel Meli Hanetho, SINTEF
ABSTRACT: Key stumbling blocks for developing 5V Li-ion batteries is the flammable electrolyte, that can result in thermal runaway and the predicted shift from cobalt electrodes which will require new electrolyte blends or cathode surfaces to be passivated. Dry cells with all solid electrolytes must be the ultimate objective in terms of safety. Moreover, solid electrolytes that are impenetrable to Li metal dendrites will enable the use of Li anodes and hence increase the energy density. Building on SINTEF’s experience in Li-ion electrodes, polymer science and function oxides, secondary batteries have become a core research area. Work presented here will detail three approaches under investigation at SINTEF for resolving the safety and stability issues of the existing Li-ion batteries: 1) Highly stable, liquid electrolyte formulations for current Li-ion battery manufacturing processes. 2) Solid-state polymer electrolytes (SPE). 3) Solid-state composite polymer-ceramic electrolytes.
|51||Prussian Blue Analogues as cathode material in low cost aqueous batteries |
Solveig Kjeldgaard, Aarhus University
ABSTRACT: In order to increase the use of sustainable energy sources like solar and wind, new solutions in terms of energy storage are needed to overcome their highly intermittent nature. For battery technologies to be relevant for grid-scale storage, the electrode materials must be low cost, environmentally benign, have high energy efficiency and long cycle life. Because of the requirement for cheap electrode materials, the choice of elements are limited to earth abundant transition metals such as iron, manganese, zinc and copper. Prussian Blue Analogues (PBAs) are investigated as cathode material in large-scale, low cost aqueous batteries. PBAs are a large family of transition metal hexacyanoferrates with the general structural formula AXM[Fe(CN)6], where A is a cation and M is a transition metal. PBAs are practically insoluble and are structurally stable towards insertion/extraction of a wide range of ions, providing good cycling capabilities.
|52||MXenes as anode materials for Li-, Na- and K-ion rechargeable batteries |
Tatiana Koriukina, Uppsala University
ABSTRACT: The work presents current results on using delaminated MXenes films (2D restacked sheets of transition metal carbides/nitrides having surface termination groups (T) such as –OH, –F or =O). Currently titanium carbide, Ti3C2Tx-compositions, are investigated as negative electrode materials for Li-, Na- and K-ion batteries. The fundamental questions to answer are: i) which electrochemical reactions occur in the electrode during cycling in a half-cell setup? ii) which species are formed during the SEI formation? and iii) how could the electrode design be altered in order to insure effective Li+(Na+, K+) intercalation into the structure? Authors attempt to answer these questions by means of coupling cycling voltammetry and galvanostatic cycling with XPS, SEM as well as synchrotron-based techniques such as HAXPES and NEXAFS. Findings will thus enable materials optimization for energy storage applications and provide suggestions on materials to be used for lithium-ion batteries and beyond.
|53||Polycarbonate-ZrO2 nano-composite electrolytes for ambient temperature solid-state batteries |
Tian Khoon Lee, Uppsala University
ABSTRACT: Polycarbonate-based polymer electrolytes have recently shown great interest after displaying promising functionalities for solid-state lithium-ion batteries. In this present work, poly(trimethylene carbonate)-ɛ-caprolactone electrolytes are developed further by the inclusion of zirconium oxide particles, prepared by an in-situ sol-gel method, resulting in PTMC80CL20-LiTFSI-ZrO2. SEM micrographs show that ZrO2 particles with 40-60 nm size are uniform in size. Contrary to many studies on filler-polymer electrolytes, the changes in ionic conductivity are insignificant upon addition of zirconia filler in this fully amorphous polymer, but remain at ~10-5 S cm-1 at room temperature. On the other hand, high lithium transference numbers in the range 0.83 to 0.87 and improved electrochemical stability at room temperature are obtained. Moreover, the stability and cyclability of the nano-composite polymer electrolyte (NCPE) is further demonstrated by plating/stripping test with Li metal electrode.
|54||Observing the solid-state formation of P2-NaxCo0.7Mn0.3O2 |
Xenia Hassing-Hansen, Aarhus University
ABSTRACT: Secondary sodium ion batteries (SIBs) have potential applications in terms of grid-scale energy storage – their lower energy densities compared with lithium analogues makes SIBs more relevant for stationary applications than for e.g. electrical vehicles (EVs). While lithium is expensive and unevenly distributed around the world, sodium can be extracted from water. The higher abundance further motivates the development of SIBs. In 2016, Y. Shen et al. reported good electrochemical properties of the cathode material, NaxCo0.7Mn0.3O2 (x≈1). In the present study, the goal was to investigate the formation of an already-reported cathode material and eventually to understand and possibly improve the synthesis. The preliminary investigation was done by trying to replicate the results of the article and additionally performing in situ experiments using in-house powder x-ray diffraction.
|55||Suppression of manganese dissolution from LiMn2O4 cathodes |
Yonas Tesfamhret, Uppsala University
ABSTRACT: Mn dissolution is known as a major degradation mechanism for LiMn2O4 (LMO) cathodes. Herein, we used atomic layer deposition (ALD) method to form a surface coating of Al2O3 on LMO particles. The uniform and thickness controlled coating improves cycling performance by preventing electrolyte/electrode interfacial reactions and reduces the surface dissolution of Mn-ions into the electrolyte . LiFePO4 (LFP) is chosen as the counter electrode as opposed to e.g. Li-metal or graphite. Using a high average potential counter electrode restricts the reduction of Mn-ions on the surface of the anode. Inductively coupled plasma optical emission spectroscopy (ICP-OES) based ex situ method is developed for determination of Mn-ions dissolved in to the electrolyte solution.
|56||Operando X-Ray Diffraction of Lithium-Sulfur Batteries with Concurrent Resistance Measurement |
Yu-Chuan Chien, Uppsala University
ABSTRACT: In this work, a modification of a coin cell was designed to preserve the electrochemical equivalence of a Li-S cell made with an unmodified coin cell while allowing X-ray radiation passing through. This design enabled in-house operando XRD with simultaneous resistance measurement performed by the Intermittent Current Interruption (ICI) method. The ICI method rendered both time-independent resistance, which is a sum of solution and charge transfer resistance, and time-dependent resistance, which is linearly proportional to the coefficient of a Warburg element used in the equivalent circuit model of electrochemical impedance spectroscopy. With the combination of operando XRD and real-time resistance values, this study investigated the correlation between the precipitation of insulating solid sulfur species and the transport properties inside the porous carbon matrix of the positive electrode.