The Experts below are selected from a list of 42 Experts worldwide ranked by ideXlab platform
Daniel S. Kirschen - One of the best experts on this subject based on the ideXlab platform.
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Modeling of lithium-ion battery degradation for cell life assessment
IEEE Transactions on Smart Grid, 2018Co-Authors: Bolun Xu, Alexandre Oudalov, Andreas Ulbig, Goran Andersson, Daniel S. KirschenAbstract:Abstract—Rechargeable lithium-ion batteries are promising candidates for building grid-level storage systems because of their high energy and power density, Low Discharge Rate, and decreasing cost. A vital aspect in energy storage planning and operations is to accuRately model the aging cost of battery cells, especially in irregular cycling operations. This paper proposes a semi-empirical lithium-ion battery degradation model that assesses battery cell life loss from operating profiles. We formulate the model by combining fundamental theories of battery degradation and our observations in battery aging test results. The model is adaptable to different types of lithium-ion batteries, and methods for tuning the model coefficients based on manufacturer’s data are presented. A cycle-counting method is incorpoRated to identify stress cycles from irregular operations, alLowing the degradation model to be applied to any battery energy storage (BES) applications. The usefulness of this model is demonstRated through an assessment of the degradation that a BES would incur by providing frequency control in the PJM regulation market.
Seung Man Baek - One of the best experts on this subject based on the ideXlab platform.
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thermal modeling of cylindrical lithium ion battery during Discharge cycle
Energy Conversion and Management, 2011Co-Authors: Dong Hyup Jeon, Seung Man BaekAbstract:Abstract Transient and thermo-electric finite element analysis (FEA) of cylindrical lithium ion (Li-ion) battery was presented. The simplified model by adopting a cylindrical coordinate was employed. This model provides the thermal behavior of Li-ion battery during Discharge cycle. The mathematical model solves conservation of energy considering heat generations due to both joule heating and entropy change. A LiCoO 2 /C battery at various Discharge Rates was investigated. The temperature profile from simulation had similar tendency with experiment. The temperature profile was decomposed with contributions of each heat sources and was presented at several Discharge Rates. It was found that the contribution of heat source due to joule heating was significant at a high Discharge Rate, whereas that due to entropy change was dominant at a Low Discharge Rate. Also the effect of cooling condition and the LiNiCoMnO 2 /C battery were analyzed for the purpose of temperature reduction.
Bolun Xu - One of the best experts on this subject based on the ideXlab platform.
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Modeling of lithium-ion battery degradation for cell life assessment
IEEE Transactions on Smart Grid, 2018Co-Authors: Bolun Xu, Alexandre Oudalov, Andreas Ulbig, Goran Andersson, Daniel S. KirschenAbstract:Abstract—Rechargeable lithium-ion batteries are promising candidates for building grid-level storage systems because of their high energy and power density, Low Discharge Rate, and decreasing cost. A vital aspect in energy storage planning and operations is to accuRately model the aging cost of battery cells, especially in irregular cycling operations. This paper proposes a semi-empirical lithium-ion battery degradation model that assesses battery cell life loss from operating profiles. We formulate the model by combining fundamental theories of battery degradation and our observations in battery aging test results. The model is adaptable to different types of lithium-ion batteries, and methods for tuning the model coefficients based on manufacturer’s data are presented. A cycle-counting method is incorpoRated to identify stress cycles from irregular operations, alLowing the degradation model to be applied to any battery energy storage (BES) applications. The usefulness of this model is demonstRated through an assessment of the degradation that a BES would incur by providing frequency control in the PJM regulation market.
Oleg Melnik - One of the best experts on this subject based on the ideXlab platform.
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dynamics of magma fLow inside volcanic conduits with bubble overpressure buildup and gas loss through permeable magma
Journal of Volcanology and Geothermal Research, 2005Co-Authors: Oleg Melnik, A A Barmin, R S J SparksAbstract:Many volcanic eruptions show transitions between extrusive and explosive behaviour. We develop a new generic model that considers concurrence between pressure buildup in the bubbles due to the viscous resistance to their growth and gas escape through the bubble network as they become interconnected. When the pressure difference between bubbles and magma reaches the strength of the material fragmentation occurs. The effect of grain size distribution on the fLow in gas-particle dispersion is modelled by two populations of particles which strongly influence the velocity of sound in the mixture. Solutions to the steady-state boundary value problem show non-uniqueness. There are at least two regimes for the fixed parameters in the magma chamber. In the Low Discharge Rate regime, fragmentation does not occur and magma rises with partial gas escape. This regime corresponds to extrusive activity. The upper regime corresponds to explosive activity. The simulations using the parameters defined at the workshop produced the folLowing results for a rhyolitic magma composition: Discharge Rate 5.5×107 kg/s; fragmentation at depth of 2585 m with magma vesicularity of 0.74; exit gas velocity varies from 200 to 450 m/s depending on the mass fraction of small particles in the fragmented mixture; exit pressure is in the range 1.5 to 3 MPa. Variation of conduit diameter d in the range 40 to 70 m gives a mass fLow Rate Q which depends on the diameter as d2.8, less strongly than for the case of viscous fLow of Newtonian liquid in a cylindrical pipe where Q∼d4. With the increase in conduit diameter, fragmentation happens later in the fLow and conduit resistance remains high. Changes in magma temperature from 700 to 950 °C lead to increase in Discharge Rate only by a factor of 4 whereas viscosity decreases by more then 8000 times.
D Neyret - One of the best experts on this subject based on the ideXlab platform.
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new pixelized micromegas detector with Low Discharge Rate for the compass experiment
arXiv: Instrumentation and Detectors, 2011Co-Authors: D Neyret, P Abbon, M Anfreville, Y Bedfer, E Burtin, C Coquelet, D Desforge, A Giganon, N Dhose, D JourdeAbstract:New Micromegas (Micro-mesh gaseous detectors) are being developed in view of the future physics projects planned by the COMPASS collaboration at CERN. Several major upgrades compared to present detectors are being studied: detectors standing five times higher luminosity with hadron beams, detection of beam particles (flux up to a few hundred of kHz/mm^{2}, 10 times larger than for the present Micromegas detectors) with pixelized read-out in the central part, light and integRated electronics, and improved robustness. Two solutions of reduction of Discharge impact have been studied, with Micromegas detectors using resistive layers and using an additional GEM foil. Performance of such detectors has also been measured. A large size prototypes with nominal active area and pixelized read-out has been produced and installed at COMPASS in 2010. In 2011 prototypes featuring an additional GEM foil, as well as an resistive prototype, are installed at COMPASS and preliminary results from those detectors presented very good performance. We present here the project and report on its status, in particular the performance of large size prototypes with an additional GEM foil.
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New pixelized Micromegas detector with Low Discharge Rate for the COMPASS experiment
2011Co-Authors: D Neyret, P Abbon, M Anfreville, Y Bedfer, E Burtin, C Coquelet, N D'hose, D Desforge, A Giganon, D JourdeAbstract:New Micromegas (Micro-mesh gaseous detectors) are being developed in view of the future physics projects planned by the COMPASS collaboration at CERN. Several major upgrades compared to present detectors are being studied: detectors standing five times higher luminosity with hadron beams, detection of beam particles (flux up to a few hundred of kHz/mm2, 10 times larger than for the present Micromegas detectors) with pixelized read-out in the central part, light and integRated electronics, and improved robustness. Two solutions for a reduction of the impact of Discharges have been studied, with Micromegas detectors using resistive layers and using an additional GEM foil. The performance of such detectors has been measured during beam test periods. A large size prototype with nominal active area and pixelized read-out has been produced and installed in the COMPASS spectrometer in 2010. In 2011 prototypes featuring an additional GEM foil, as well as a resistive prototype, were tested in similar conditions and preliminary results from those detectors are very promising. We present here the project and report on its status, in particular the performance of large size prototypes with an additional GEM foil.
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New pixelized Micromegas detector with Low Discharge Rate for the COMPASS experiment
IEEE Nuclear Science Symposuim & Medical Imaging Conference, 2010Co-Authors: D NeyretAbstract:New Micromegas (Micro-mesh gaseous) detectors are being developed in view of the future physics projects planned by the COMPASS collaboration at CERN. The two objectives for the future detectors are to make active their central area which sees the beam, and to make them stand hadron beam flux five time higher than the present detectors. These objectives require different changes in the detector structures: pixelized area in the center, reduction of the Discharges Rate, integRated electronics and improved robustness. We report here studies done in COMPASS environment with simplified pixelized prototypes in 2009 and with close to final design detectors in 2010. We also show results from beam tests with small prototypes using different solutions to reduce the Discharges Rate: adding a GEM foil, and using resistive board.
