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[en] Renewable energies are asked for more and more worldwide. Even though they cannot generate electricity 8760 h/a year. This can be accomplished by flexible conventional power stations as well as storage systems. Especially the storage systems have to be developed technical wise and especially economic wise. An example of an integrated approach is the methanol production with a coal fired power plant. An overview showing the technical features as well as the strategic opportunities of such kind of approach is given.
[en] What existed first, the energy problem or the energy transition? For the clarification of this question the author gives a survey about the actual situation of our energy demand and the means and ways to its satisfaction. The reader learns to know the function of numerous energy transformers, from the wind mill via the automobile motor until the solar cell. The advantages and disadvantages of the different transformers are explained, just so their efficiencies and cost as well as the physical natural laws, which they must obey. A perpetuum mobile doesn't exist, but indeed an almost inexhaustible energy source, the sun, which can meet many thousandfold our demand, if we use it intelligently. Who has read this book can go confidently in each discussion about the energy problem and the energy transition.
[en] The utilization of CO_2 in Li-CO_2 batteries is attracting extensive attention. However, the poor rechargeability and low applied current density have remained the Achilles' heel of this energy device. The gel polymer electrolyte (GPE), which is composed of a polymer matrix filled with tetraglyme-based liquid electrolyte, was used to fabricate a rechargeable Li-CO_2 battery with a carbon nanotube-based gas electrode. The discharge product of Li_2CO_3 formed in the GPE-based Li-CO_2 battery exhibits a particle-shaped morphology with poor crystallinity, which is different from the contiguous polymer-like and crystalline discharge product in conventional Li-CO_2 battery using a liquid electrolyte. Accordingly, the GPE-based battery shows much improved electrochemical performance. The achieved cycle life (60 cycles) and rate capability (maximum applied current density of 500 mA g"-"1) are much higher than most of previous reports, which points a new way to develop high-performance Li-CO_2 batteries. (copyright 2017 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)
[en] Developing flexible Li-CO_2 batteries is a promising approach to reuse CO_2 and simultaneously supply energy to wearable electronics. However, all reported Li-CO_2 batteries use liquid electrolyte and lack robust electrolyte/electrodes structure, not providing the safety and flexibility required. Herein we demonstrate flexible liquid-free Li-CO_2 batteries based on poly(methacrylate)/poly(ethylene glycol)-LiClO_4-3 wt %SiO_2 composite polymer electrolyte (CPE) and multiwall carbon nanotubes (CNTs) cathodes. The CPE (7.14 x 10"-"2 mS cm"-"1) incorporates with porous CNTs cathodes, displaying stable structure and small interface resistance. The batteries run for 100 cycles with controlled capacity of 1000 mAh g"-"1. Moreover, pouch-type flexible batteries exhibit large reversible capacity of 993.3 mAh, high energy density of 521 Wh kg"-"1, and long operation time of 220 h at different degrees of bending (0-360 ) at 55 C. (copyright 2017 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)
[en] Li-ion batteries are increasingly used in hybrid electric vehicles (HEV), electric vehicles (EV) and stationary storage applications. Those applications are significantly different in terms of storage capacity, life cycles and charging times from consumer type batteries such as mobile phones and handheld tools. Naturally, those HEV and EV Li-ion batteries also differ significantly in chemical composition and size. Coherently, a recycling concept has been developed for HEV, EV and stationary storage Li-ion batteries. This concept is based on the existing IME-ACCUREC recycling process for consumer type batteries. This work describes the whole process development including slag design, test series in a lab-scale electric arc furnace and a 1 t scale trial in a top blown rotary converter.
[en] In this work, new methods for characterizing the electrochemical and thermal behavior of lithium-ion cells are presented. Based on these, a modeling approach is presented that is able to represent the cell behavior in four domains (static and dynamic for electrochemical and thermal behavior) separately. This enables transferability to a wide range of material chemistries, scalable accuracy and parameterization that can be automated.
[de]In dieser Arbeit werden neue Verfahren zur Charakterisierung des elektrochemischen und thermischen Verhaltens von Lithium-Ionen Zellen vorgestellt. Basierend auf diesen wird ein Modellansatz vorgestellt, der das Zellverhalten in vier Domänen (statisch und dynamisch für elektrochemisches und thermisches Verhalten) getrennt abzubilden vermag. Hierdurch wird die Übertragbarkeit auf verschiedenste Materialchemien, skalierbare Genauigkeit und eine automatisierbare Parametrierung möglich.
[en] Wind energy is an important field of development for the island of Gotland, Sweden, especially since the island has set targets to generate 100% of its energy from renewable sources by 2025. Due to the variability of wind conditions, energy storage will be an important technology to facilitate the continued development of wind energy on Gotland and ensure a stable and secure supply of electricity. In this study, the feasibility of utilizing the Middle Cambrian Faludden sandstone reservoir on Gotland for Compressed Air Energy Storage (CAES) is assessed. Firstly, a characterization of the sandstone beneath Gotland is presented, which includes detailed maps of reservoir thickness and top reservoir structure. Analysis of this information shows that the properties of the Faludden sandstone and associated cap rock appear favorable for the application of CAES. Seven structural closures are identified below the eastern and southern parts of Gotland, which could potentially be utilized for CAES. Scoping estimates of the energy storage capacity and flow rate for these closures within the Faludden sandstone show that industrial scale CAES could be possible on Gotland.
[en] Sodium (Na)-ion batteries (NIBs) are considered promising alternative candidates to the well-commercialized lithium-ion batteries, especially for applications in large-scale energy storage systems. The electrochemical performance of NIBs such as the cyclability, rate capability, and voltage profiles are strongly dependent on the structural and morphological evolution, phase transformation, sodium-ion diffusion, and electrode/electrolyte interface reconstruction during charge–discharge cycling. Therefore, in-depth understanding of the structure and kinetics of electrode materials and the electrode/electrolyte interfaces is essential for optimizing current NIB systems and exploring new materials for NIBs. Recently, rapid progress and development in spectroscopic, microscopic, and scattering techniques have provided extensive insight into the nature of structural evolution, morphological changes of electrode materials, and electrode/electrolyte interface in NIBs. Here in this review, a comprehensive overview of both static (ex situ) and real-time (in situ or in operando) techniques for studying the NIBs is provided. Lastly, special focus is placed on how these techniques are applied to the fundamental investigation of NIB systems and what important results are obtained.
[en] The transition of the energy system to a system based on renewable energies leads to new requirements for the balancing of load and generation at any time. One of the main flexibility options, besides flexibility of thermal generation and demand side management, are storages. Therefore, a strong discussion on cost-efficiency of storages in the future electricity system exists. Consequently this paper aims at developing a methodology to evaluate the profitability of storages under special consideration of the different electricity markets (e. g. spot and balancing). For this, future prices for spot and balancing (both power and energy) are simulated by application of a fundamental model of the future electricity market. Based on these prices the profitability of storages is analyzed by methods of power plant dispatch. Concluding different storage technologies (e. g. pumped hydro, batteries) are compared considering necessary investment costs and achieved contribution margins.