A5078966062- Advancements in Battery Materials
- Advanced Battery Materials and Technologies
- Advanced Battery Technologies Research
- Catalytic Processes in Materials Science
- Supercapacitor Materials and Fabrication
- Recycling and Waste Management Techniques
- Extraction and Separation Processes
- Graphene research and applications
- Mesoporous Materials and Catalysis
- Nuclear and radioactivity studies
- Graphite, nuclear technology, radiation studies
- Mining and Gasification Technologies
- Layered Double Hydroxides Synthesis and Applications
- Coal Combustion and Slurry Processing
- Carbon Nanotubes in Composites
- Ammonia Synthesis and Nitrogen Reduction
- Electrocatalysts for Energy Conversion
- Electrochemical Analysis and Applications
- Electrodeposition and Electroless Coatings
- Advanced biosensing and bioanalysis techniques
- Coal and Coke Industries Research
- Hybrid Renewable Energy Systems
- Nanomaterials for catalytic reactions
- Fuel Cells and Related Materials
- Inorganic and Organometallic Chemistry
Technical University of Munich
2010-2021
Technical University of Applied Sciences Wildau
2009
The instability of currently used electrolyte solutions and the carbon support during charge–discharge in non-aqueous lithium–oxygen cells can lead to discharge products other than desired Li2O2, such as Li2CO3, which is believed reduce cycle-life. Similarly, an O2 atmosphere contains H2O CO2 impurities would LiOH Li2CO3 products. In this work we therefore investigate rechargeability model cathodes pre-filled with four possible Li–air cell products, namely LiOH, Li2O. Using Online...
The quality of metal oxide-based battery active materials is compromised by surface contamination from storage and handling at ambient conditions. We present a detailed analysis the true nature quantity contaminants on two different cathode materials, widely used LiNi1/3Co1/3Mn1/3O2 (NCM111) Ni-rich LiNi0.8Co0.1Mn0.1O2 (NCM811). process these in three distinct conditions "wet" (excessive exposure to moisture), "dry" (standard drying as-received materials), "calcined" (heat-treatment...
The electrochemical oxidation of LiPF6-based electrolytes is reported to generate POF3 gas. In order enable a quantitative analysis the LiPF6 decomposition reactions, we aimed establish calibration factors for and PF5 in on-line mass spectrometry (OEMS). Thermal dry expected yield PF5, but instead all detected as our OEMS setup, rendering differentiation two gases impossible presenting an artefact which likely occurs with most systems due high reactivity PF5. However, can still determine...
Lowering of the oxygen evolution reaction (OER) noble metal catalyst loading on anode a polymer electrolyte membrane water electrolysis (PEMWE) is necessity for enabling large-scale hydrogen production based this technology. This study introduces remarkably active OER that dispersion Ir nanoparticles highly conductive oxide support. The was designed in way to combine all characteristics have been reported enhance activity an oxide-based catalyst, including high and controlling particle size,...
In this study we report on the direct proportionality between cathode surface area and first discharge capacity of non-aqueous Li-O2 cells using ether-based electrolytes. Seven different highly structured carbon blacks, characterized by areas porosities, were used to prepare non-catalyzed cathodes. Surface measurements porosity analyzes carried out both raw materials electrodes in order estimate fraction accessible electrolyte. The specific cathodes was then normalized over its a strong...
Sulfide-based solid electrolytes (SE) are quite attractive for application in all-solid-state batteries (ASSB) due to their high ionic conductivities and low grain boundary resistance. However, limited chemical electrochemical stability demands protection on both cathode anode side. One promising concept prevent unwanted reactions simultaneously improve interfacial contacting at the side consists applying a thin polymer film as interlayer between Li metal SE. In present study, we...
The decomposition of lithium peroxide during the charging process lithium–air batteries is investigated. A novel preparation method for electrodes in discharged state, i.e., prefilled with Li2O2 using polyethylene oxide as a binder, presented. composition and reactivity Li2O2-prefilled are examined by thermal analysis coupled on-line mass spectrometry. Voltage profiles gas evolution battery cells correlated its impact on other electrode compounds. It found that both electrochemical enhance...
Layered Ni-rich transition metal oxides like so-called NCMs are one of the most-promising high-energy density cathode active materials (CAMs) for next-generation Li-Ion batteries. However, compared to with low nickel content, suffer from a highly reactive surface that leads an accumulation contaminants and also higher soluble base content. Since detailed understanding formation rate is still lacking, we will investigate effect extended storage in high relative humidity air NCM851005 (Li 1+ δ...
The fluorinated phosphate lithium bis (2,2,2-trifluoroethyl) (LiBFEP) has been investigated as a film-forming additive employed to passivate the cathode and hinder continuous oxidation of electrolyte. Cyclic voltammetry (CV) linear sweep coupled with online electrochemical mass spectrometry (LSV-OEMS) on conductive carbon electrode (i.e., C65/PVDF composite) showed that LiBFEP decreases electrolyte (CV LSV) LiPF6 decomposition at high potentials. Incorporation (0.1 0.5 wt%) into in ethylene...
In this study, we present a novel surface modification approach via SO2 gas treatment at 200 °C–400 °C to enhance the electrochemical performance of Li and Mn-rich cathode materials 0.35Li2MnO3·0.65LiNi0.35Mn0.45Co0.20O2 (HE-NCM) for advanced lithium-ion batteries. It was established by X-ray photoelectron spectroscopy that leads formation sulfates sulfites on material, while bulk remains unaffected, as confirmed electron diffraction studies. Based results obtained, proposed possible...
To develop reversible Li-O2 batteries, the need for novel carbon-free cathode materials is evident. In this study, we present hydrothermal synthesis of highly conductive crystalline antimony doped tin oxide (ATO) nanoparticles, fabrication ATO electrodes with high surface area, and their application as cathodes in aprotic cells. We use a pressure transducer an online electrochemical mass spectrometer to quantify consumed evolved gases during discharge charge Solid products on are identified...
To increase the specific capacity of layered transition metal oxide based cathode active materials (CAMs) for Li-ion batteries such as NCMs (Li(Ni x Co y Mn z )O 2 , with + = 1), two major strategies are pursued: (i) increasing Ni content (beyond, e.g., NCM811 0.8 and 0.1) or (ii) using Li- Mn-rich (LMR-NCMs) which can be represented by formula Li MnO 3 · (1−x) LiNi O . Unfortunately, these strongly react CO moisture in ambient: Ni-rich due to high reactivity nickel, LMR-NCMs their ≈10-fold...
It is commonly accepted that today’s Li-ion technologies might have issues addressing future long term targets. 1 Hence there an increasing focus on novel cell designs. Solid electrolytes (SE) attracted growing interest as they could enable the use of lithium metal. They feature several advantages over liquid electrolytes, such a rigid and non-leaking structure, non-flammability well larger temperature operation range. 2 All-solid-state batteries thus great potential to enhance safety,...
Layered Oxides such as NCM111 are state-of-the-art cathode active materials (CAMs) for commercial applications well promising candidates even higher energy density batteries by raising the nickel content up to 80% (NCM811) and beyond. 1 However, recent studies 2–4 have demonstrated high reactivity of Ni-rich CAMs with CO 2 moisture, which is highly problematic industrial electrode manufacturing processes. In addition, electrochemical performance NCM811 drastically deteriorated moisture...
Li-O 2 cells are very promising energy conversion devices because of the theoretical specific capacity that they could provide (1). Unfortunately also challenging regarding instability their components, like electrolyte solvent (2-4) and carbon electrode (5, 6) mostly due to reactivity superoxide ion radical during discharge or other reactive oxygen species in charge. Also binder used O -electrode reactivity, which have a strong effect on reactions (7, 8), even though its cell behavior has...
Abstract not Available.
The performance of metal oxide-based battery active materials is compromised by surface contaminants formed during storage and handling in ambient air. We present a detailed analysis the true nature quantity these on three different cathode (CAMs), widely used LiNi 1/3 Mn Co O 2 (NMC111), high area Li- Mn-rich xLi MnO 3 •(1-x)LiNi b c (HE-NMC), Ni-rich 0.6 0.2 (NMC622) 0.8 0.1 (NMC811). process distinct conditions “dry” (as-received dried at 120 °C), “wet” (excessive air exposure relative...
Ni-rich cathode materials like NCM811 (Li 1+x (Ni 0.8 Co 0.1 Mn ) 1-x O 2 are promising candidates for reaching the energy density targets of Li-Ion batteries automotive applications [1]. However, these show a rapid performance decrease when stored under ambient conditions [2]. The is often related to formation surface impurities containing M-CO 3 and M-OH groups on active material [2, 3, 4]. In this work, we investigate influence different storage parameters contaminants using TGA-MS XPS....