Poster: Operando X-Ray Diffraction of Lithium-Sulfur Batteries with Concurrent…

Presenter: Yu-Chuan Chien
Title: Operando X-Ray Diffraction of Lithium-Sulfur Batteries with Concurrent Resistance Measurement
Affiliation: 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.

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Poster: Suppression of manganese dissolution from LiMn2O4 cathodes

Authors: Yonas Tesfamhret, Erik Berg and Reza Younesi
Title: Suppression of manganese dissolution from LiMn2O4 cathodes
Affiliation: Department of Chemistry-Ångström Laboratory, Uppsala University, Box 538, SE-75121 Uppsala, Sweden

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 [1]. 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.

Reference:
[1] A. Bhandari, J. Bhattacharya, J. Electrochem. Soc. 2017, 164.

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Poster: Observing the solid-state formation of P2-NaxCo0.7Mn0.3O2

Presenter: Xenia Hassing-Hansen
Title: Observing the solid-state formation of P2-NaxCo0.7Mn0.3O2
Affiliation: 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.

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Poster: Polycarbonate-ZrO2 nano-composite electrolytes for ambient temperature solid-state batteries

Presenter: Tian Khoon Lee
Title: Polycarbonate-ZrO2 nano-composite electrolytes for ambient temperature solid-state batteries
Affiliation: Department of Chemistry-Ångström Laboratory, Uppsala University, Box 538, SE-75121 Uppsala, Sweden

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.

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Poster: Polycarbonate-ZrO2 nano-composite electrolytes for ambient temperature solid-state batteries

Author: Tian Khoon Lee
Title: Polycarbonate-ZrO2 nano-composite electrolytes for ambient temperature solid-state batteries
Affiliation: 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.

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Poster: MXenes as anode materials for Li-, Na- and…

Author: Tatiana Koriukina
Title: MXenes as anode materials for Li-, Na- and K-ion rechargeable batteries
Affiliation: 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.

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Poster: Prussian Blue Analogues as cathode material in low…

Presenter: Solveig Kjeldgaard
Title: Prussian Blue Analogues as cathode material in low cost aqueous batteries
Affiliation: 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.

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Poster: Strategies targeting 5V Li-ion batteries

Authors: Sidsel Meli Hanetho, Peter Molesworth and Nils Peter Wagner
Title: Strategies targeting 5V Li-ion batteries
Affiliation: 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.

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Poster: Modelling Capacity Fade in Silicon Graphite Composite Electrodes

Author: Shweta Dhillon
Title: Modelling Capacity Fade in Silicon Graphite Composite Electrodes
Affiliation: 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.

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Poster: Optimisation of printed film densification for sodium nickel…

Presenter: Robert Mitchell
Title: Optimisation of printed film densification for sodium nickel chloride (Na-Ni-CI) batteries
Affiliation: Center for Process Innovation, CPI, United Kingdom

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.

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