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[en] Interest in electrical energy storage systems is increasing as the opportunities for their application become more compelling in an industry with a back-drop of ageing assets, increasing distributed generation and a desire to transform networks into Smart Grids. A field trial of an energy storage system designed and built by ABB is taking place on a section of 11 kV distribution network operated by EDF Energy Networks in Great Britain. This paper reports on the findings from simulation software developed at Durham University that evaluates the benefits brought by operating an energy storage system in response to multiple events on multiple networks. The tool manages the allocation of a finite energy resource to achieve the most beneficial shared operation across two adjacent areas of distribution network. Simulations account for the key energy storage system parameters of capacity and power rating. Results for events requiring voltage control and power flow management show how the choice of operating strategy influences the benefits achieved. The wider implications of these results are discussed to provide an assessment of the role of electrical energy storage systems in future Smart Grids.
[en] It is well known, that the electrical energy storage in the large scale is basically a difficult process. Such a process is connected with energy losses, as most frequently it is the conversion of electrical energy into another form, for example mechanical, and then back to the primal electrical form. Though, the SMES technology offers the energy storage in an unchanged form, which is advantageous primarily in the achieved efficiency. The magnetic resonance imaging (MRI) devices, commonly used in the medical facilities are based on the basis of superconducting magnet. After its rejection from operation, (basically caused only by its 'software fustiness' and not by functional faults), there is a possibility of using such devices for the energy storage purposes. Additionally, such a technology of storage is also ecological. A research project is running at the Faculty of Mining, Ecology, Process Control and Geotechnologies, the Department of Business and Management, in the field of using rejected MRI for energy storage purposes. (authors)
[en] Highlights: • Performance analysis for lithium storage technologies, such as Li[NiCoMn]O2 and LiFePO4 batteries. • Actual capacity of lithium technologies analyzed almost close to their nominal capacity also for high discharging current. • The charging efficiency for Li[NiCoMn]O2 positively affects the regenerative breaking and fast recharging operations. • The analyzed battery packs follow dynamic power requirements on performed road driving cycles. • Experimental results demonstrate driving range is much higher when battery packs are based on lithium technology. - Abstract: This paper deals with an experimental evaluation regarding the real performance of lithium based energy storage systems for automotive applications. In particular real working operations of different lithium based storage system technologies, such as Li[NiCoMn]O2 and LiFePO4 batteries, are compared in this work from the point of view of their application in supplying full electric and hybrid vehicles, taking as a reference the well-known behavior of lead acid batteries. For this purpose, the experimental tests carried out in laboratory are firstly performed on single storage modules in stationary conditions. In this case the related results are obtained by means of a bidirectional cycle tester based on the IGBT technology, and consent to evaluate, compare and contrast charge/discharge characteristics and efficiency at constant values of current/voltage/power for each storage technology analyzed. Then, lithium battery packs are tested in supplying a 1.8 kW electric power train using a laboratory test bench, based on a 48 V DC bus and specifically configured to simulate working operations of electric vehicles on the road. For this other experimentation the test bench is equipped with an electric brake and acquisition/control system, able to represent in laboratory the real vehicle conditions and road characteristics on predefined driving cycles at different slopes. The obtained experimental results on both charge/discharge tests and driving cycles demonstrate the advantages of using lithium technologies, mainly in terms of their high efficiency, particularly at high current values. That represents a feasible solution to offer vehicle designers and users extended driving ranges and reduced recharging times
[en] There is a big fuss over a new amendment regarding waste. After SNS MP's created an uproar with proposals concerning packages, critics of electrowaste law clauses are also starting to talk. According to them, there is a threat that the MP's will overprice certain products along with batteries. One of the main reasons behind the waste legislation amendations is an obligation to incorporate directives regarding batteries and accumulators into Slovak rule of law. While so far the law has been accommodating mostly automobile and industrial batteries and accumulators, the amendment refers to all kinds. For these products, money should be put into the Recycling Fund, unlike electrowaste, where producers and importers pay the fund only if they don't meet the requirements for collecting and processing which are normally arranged via collective organizations. The Slovak IT Association estimates that due to new rules the price of certain batteries and accumulators might increase by 15 to 160%. (author)
[en] Electrofuel Inc. develops, manufactures and sells a lithium ion superpolymer rechargeable battery technology. This unique and breakthrough technology provides the highest energy density and longest lasting portable power source on the market today. The company's goal is to become the leading provider of portable power for the portable computer and wireless sectors and to apply its technology to a wide range of alternative energy applications. The market for this technology is large and growing rapidly. Sales have increased from 190 million devices in 1998 to a projected 600 million in 2003. The increased sales are driven by better affordability, reduced size and functionality of the battery. This annual report highlights some of the major milestones the company achieved in 2000 which helped advance the corporate strategy and which marked its transformation from a late stage development company to an early stage commercial manufacturer. The report also contains statements regarding the outlook for the company's business and results of operations. The customary consolidated financial statement including balance sheets, assets, liabilities and capital were also included. tabs., figs
[en] In this paper, a health auxiliary diagnosis method based on Sample Entropy (SampEn) is proposed for the lead-acid battery unit. The concept of the proposed method is that the discharging curve for a health battery unit is smooth; however, the degradation of battery unit caused by the internal shorts, opening of internal short or cell undergoing reversal will distort the discharging curve. Since SampEn can quantify the regularity of a data sequence, it can serve as an indicator for the state-of-health (SOH) of the lead-acid battery. The salient feature of the proposed method is that SOH of the battery is estimated automatically at the end of each discharging cycle by measuring the battery voltage and current of a battery unit, so that no complicated measurement is required. To verify the proposed health auxiliary diagnosis method based on SampEn, aging experiments on lead-acid battery are developed. The experimental data shows that the proposed health auxiliary diagnosis method provides the expected results.
[en] The structure of a polymer electrolyte, P(EO)7.5LiN (SO2 CF3)2 , has been determined by neutron diffraction with isotropic substitution. The Li ions are bonded on average to five ether oxygens belonging to pairs of PEO coils. These are arranged with a considerable degree of extended-range order providing pathways for the Li ion conduction. The lack of ion pairing in this system below 4.8 Angstrom is reminiscent of that observed in the remarkable structure of P(EO)6LiAsF 6 and implies that anions and cations are free to migrate independently. (c) 2000 The American Physical Society
[en] In this paper we describe the principles of individual components of the system used for research in the field of heat production and storage, which is currently being built and completed in the laboratory of the Department of Environmental Physics at the Faculty of Mathematics, Physics and Informatics, Comenius University in Bratislava. This system consists of three heat storers filled with storage material of own production, one heat storer filled with water, while vacuum heat collectors are used as heat sources, but also heat from pyrolysis and electrolysis. The paper focuses on the production of heat by solar heat collectors, while other heat sources are briefly described. Different methods and processes of heat storage are also compared, with emphasis on the use of materials with phase change, which allow the use of heat storage in their phase change. In this paper, we also compare the behavior of self-produced storage material using a phase change without and with an added additive, which reduces the stratification of individual components of storage material after several discharging and charging cycles. In addition to the description of the system itself, the expected theoretical energy gains of solar heat collectors are calculated on the basis of meteorological models and measured data during the year, as well as the first measured results during the first month of solar heat collectors. (authors)
[en] The aim of the contribution is to describe the claim of environmental friendly act with dangerous waste C especially batteries and accumulators) in Slovakia. The article is concerned on the systems with act on dangerous waste and the choice of recovery technologies. Present situation of Slovakia is documented by the example of the situation in Banska Bystrica. (authors)
[en] A packed bed thermal storage has several desirable characteristics to be used for energy storage. The behavior of packed bed is predicted by set of differential equations. A numerical solution is developed for packed bed storage tank accounting to the secondary phenomena of thermal losses and conduction effect. The effect of heat loss to surrounding (K1), and air capacitance (K2) and air capacitance (K3) are examined in the numerical solution. It is found that the values of K1 and K2 are small and can practically be neglected in the solution. The solution indicates the profiles of air and rock bed temperatures with respect to time and length of the bed