The Experts below are selected from a list of 294 Experts worldwide ranked by ideXlab platform
Yu Guo - One of the best experts on this subject based on the ideXlab platform.
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Heat Generation by spin-polarized current in a quantum-dot spin battery
Physics Letters A, 2015Co-Authors: Feng Chi, Lian-liang Sun, Jun Zheng, Yu GuoAbstract:Abstract We study the Heat Generation by spin-polarized current due to the electron–phonon coupling in a single-level quantum-dot, which is connected to an external either symmetric or asymmetric dipolar spin battery. We find that the Heat Generation depends sensitively on the configuration of the spin battery's chemical potentials. In the case of the dot coupled to symmetric spin battery, there is remarkable negative differential of the Heat Generation, which disappears if the spin battery is asymmetric. We also find that the magnitude of the Heat Generation in asymmetric spin battery is much larger than that in symmetric one despite of the reduced intensity of the electric current. Moreover, the Heat Generation is insensitive to the system's temperature, and develops peaks when the dot-lead coupling strength or the intradot Coulomb interaction approaches the phonon's energy quanta.
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Heat Generation by electronic current in a quantum dot spin-valve
Journal of Applied Physics, 2014Co-Authors: Feng Chi, Lian-liang Sun, Yu GuoAbstract:Electric-current-induced Heat Generation in an interacting single-level quantum dot connected to ferromagnetic leads with noncollinear magnetizations is theoretically investigated. We find that when the two leads' spin polarization rates are identical and much smaller than unit, the magnitude of the Heat Generation is almost monotonously enhanced as the angle between the leads' magnetic moments is varied from zero to π, while the magnitude of the electric current is continuously suppressed. Moreover, the properties of the Heat Generation depend on the lead's spin polarization rate in different ways when the angle is varied. If at least one of the leads' spin polarization rate approaches to unit, the spin-valve effect of the Heat Generation is identical to that of the electric current. Now the previously found negative differential of the Heat Generation disappears when the angle approaches to π. As compared to the current, the Heat Generation is more sensitive to the system's asymmetry when one of the electrodes is half-metallic in noncollinear configurations.
Wei Shyy - One of the best experts on this subject based on the ideXlab platform.
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Intercalation-Induced Stress and Heat Generation within Single Lithium-Ion Battery Cathode Particles
Journal of The Electrochemical Society, 2008Co-Authors: Xiangchun Zhang, Ann Marie Sastry, Wei ShyyAbstract:Intercalation-induced stress and Heat Generation inside Li-ion battery cathode LiMn2O4 particles under potentiodynamic control are simulated in this paper. We combined analyses of transport and kinetics in determining resulting stresses, which arise from concentration gradients in cathode particles, and Heat Generation. Two peaks in boundary reaction flux, and resulting stresses, were determined from the modeling of electrochemical kinetics and diffusion, using intrinsic material properties resulting in two plateaus in the open-circuit potential and the applied potential. Resistive Heating was identified as the most important Heat Generation source. To probe the impact of the particle shape equivalent radius and aspect ratio of an ellipsoidal particle and the potential sweep rate on stress and Heat Generation, a surrogate-based analysis was also conducted. The systematic study showed that both intercalation-induced stress and time-averaged resistive Heat Generation rate increase with particle radius and potential sweep rate. Intercalation-induced stress increases first, then decreases as the aspect ratio of an ellipsoidal particle increases, whereas time-averaged resistive Heat Generation rate decreases as aspect ratio increases. This surrogate-based analysis suggests that ellipsoidal particles with larger aspect ratios are preferred over spherical particles, in improving battery performance when stress and Heat Generation are the only factors considered.
Feng Chi - One of the best experts on this subject based on the ideXlab platform.
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Heat Generation by spin-polarized current in a quantum-dot spin battery
Physics Letters A, 2015Co-Authors: Feng Chi, Lian-liang Sun, Jun Zheng, Yu GuoAbstract:Abstract We study the Heat Generation by spin-polarized current due to the electron–phonon coupling in a single-level quantum-dot, which is connected to an external either symmetric or asymmetric dipolar spin battery. We find that the Heat Generation depends sensitively on the configuration of the spin battery's chemical potentials. In the case of the dot coupled to symmetric spin battery, there is remarkable negative differential of the Heat Generation, which disappears if the spin battery is asymmetric. We also find that the magnitude of the Heat Generation in asymmetric spin battery is much larger than that in symmetric one despite of the reduced intensity of the electric current. Moreover, the Heat Generation is insensitive to the system's temperature, and develops peaks when the dot-lead coupling strength or the intradot Coulomb interaction approaches the phonon's energy quanta.
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Heat Generation by electronic current in a quantum dot spin-valve
Journal of Applied Physics, 2014Co-Authors: Feng Chi, Lian-liang Sun, Yu GuoAbstract:Electric-current-induced Heat Generation in an interacting single-level quantum dot connected to ferromagnetic leads with noncollinear magnetizations is theoretically investigated. We find that when the two leads' spin polarization rates are identical and much smaller than unit, the magnitude of the Heat Generation is almost monotonously enhanced as the angle between the leads' magnetic moments is varied from zero to π, while the magnitude of the electric current is continuously suppressed. Moreover, the properties of the Heat Generation depend on the lead's spin polarization rate in different ways when the angle is varied. If at least one of the leads' spin polarization rate approaches to unit, the spin-valve effect of the Heat Generation is identical to that of the electric current. Now the previously found negative differential of the Heat Generation disappears when the angle approaches to π. As compared to the current, the Heat Generation is more sensitive to the system's asymmetry when one of the electrodes is half-metallic in noncollinear configurations.
Grant Unsworth - One of the best experts on this subject based on the ideXlab platform.
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Measurements of Heat Generation in prismatic Li-ion batteries
Journal of Power Sources, 2014Co-Authors: Kaiwei Chen, Grant UnsworthAbstract:Abstract An accurate understanding of the characteristics of battery Heat Generation is essential to the development and success of thermal management systems for electric vehicles. In this study, a calorimeter capable of measuring the Heat Generation rates of a prismatic battery is developed and verified by using a controllable electric Heater. The Heat Generation rates of a prismatic A123 LiFePO 4 battery is measured for discharge rates ranging from 0.25C to 3C and operating temperature ranging from −10 °C to 40 °C. At low rates of discharge the Heat Generation is not significant, even becoming endothermic at the battery operating temperatures of 30 °C and 40 °C. Heat of mixing is observed to be a non-negligible component of total Heat Generation at discharge rates as low as 0.25C for all tested battery operating temperatures. A double plateau in battery discharge curve is observed for operating temperatures of 30 °C and 40 °C. The developed experimental facility can be used for the characterization of Heat Generation for any prismatic battery, regardless of chemistries.
Xiangchun Zhang - One of the best experts on this subject based on the ideXlab platform.
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Intercalation-Induced Stress and Heat Generation within Single Lithium-Ion Battery Cathode Particles
Journal of The Electrochemical Society, 2008Co-Authors: Xiangchun Zhang, Ann Marie Sastry, Wei ShyyAbstract:Intercalation-induced stress and Heat Generation inside Li-ion battery cathode LiMn2O4 particles under potentiodynamic control are simulated in this paper. We combined analyses of transport and kinetics in determining resulting stresses, which arise from concentration gradients in cathode particles, and Heat Generation. Two peaks in boundary reaction flux, and resulting stresses, were determined from the modeling of electrochemical kinetics and diffusion, using intrinsic material properties resulting in two plateaus in the open-circuit potential and the applied potential. Resistive Heating was identified as the most important Heat Generation source. To probe the impact of the particle shape equivalent radius and aspect ratio of an ellipsoidal particle and the potential sweep rate on stress and Heat Generation, a surrogate-based analysis was also conducted. The systematic study showed that both intercalation-induced stress and time-averaged resistive Heat Generation rate increase with particle radius and potential sweep rate. Intercalation-induced stress increases first, then decreases as the aspect ratio of an ellipsoidal particle increases, whereas time-averaged resistive Heat Generation rate decreases as aspect ratio increases. This surrogate-based analysis suggests that ellipsoidal particles with larger aspect ratios are preferred over spherical particles, in improving battery performance when stress and Heat Generation are the only factors considered.
