Search

Your search keyword '"Jiao, Qingjie"' showing total 56 results
Start Over Author "Jiao, Qingjie" Publisher elsevier bv
56 results on '"Jiao, Qingjie"'

21. Mathematical model for thermal behavior of lithium ion battery pack under overcharge

Author

Chuang Qi, Zhu Yanli, Jiao Qingjie, Fei Gao, and Kai Yang

Subjects
Fluid Flow and Transfer Processes, Battery (electricity), Overcharge, Materials science, Thermal runaway, 020209 energy, Mechanical Engineering, 02 engineering and technology, Heat transfer coefficient, Condensed Matter Physics, Electrochemistry, Thermal, Electrode, 0202 electrical engineering, electronic engineering, information engineering, Composite material, Voltage
Abstract

An overcharge model of lithium ion battery pack was built by coupling the electrochemical model with thermal abuse model. The pack consists of three fully-charged batteries, each of which has a capacity of 10 Ah, using Li[Ni1/3Co1/3Mn1/3]O2 as the positive electrode. The three batteries in the pack were juxtaposed, and only the middle one was overcharged. The influences of current, convection coefficient and gap between batteries on the thermal runaway propagation were studied. The results of temperature and voltage obtained from the models were validated experimentally, and they were agreed well with the experimental data with the relative error within 6%. The results showed that the onset temperature of thermal runaway of the charged battery increased with an increase in the current, while the temperatures for the other two decreased. The temperature rate of the charged battery changed little when the convection coefficient was greater than 40 W/m2 K. The clamp of lithium ion battery pack had an important effect on the thermal runaway propagation. The occurrence of thermal runaway propagation was depended on whether there was the existence of clamp when the battery gap exceeded 5 mm.

Published
2018

37. Safety analysis of lithium-ion battery by rheology-mutation theory coupling with fault tree method

Author

Jiao Qingjie, Zhu Yanli, Kai Yang, Chuang Qi, Fei Gao, and Wang Songcen

Subjects
Fault tree analysis, Battery (electricity), Coupling, Engineering, business.industry, 020209 energy, General Chemical Engineering, Energy Engineering and Power Technology, Wear coefficient, 02 engineering and technology, Mechanics, Structural engineering, Management Science and Operations Research, 021001 nanoscience & nanotechnology, Collision, Industrial and Manufacturing Engineering, Rheology, Control and Systems Engineering, Minimum cut, 0202 electrical engineering, electronic engineering, information engineering, 0210 nano-technology, Safety, Risk, Reliability and Quality, business, Food Science, Event (probability theory)
Abstract

The safety of LIB (lithium-ion battery) was analyzed by the rheology-mutation theory and FTA (fault tree analysis) method. The explosion process of LIB can be viewed as a rheology-mutation process. The process of safety rheology with time can be divided into three stages: decelerated, stable and accelerated growth stage, respectively. The physical model and mathematic model were built to estimate the probability of LIB explosion based on the rheology-mutation theory. The influence of different parameters, like external force, strength coefficient and wear coefficient, on probability of LIB explosion were discussed. The results showed that the external force is the most important parameter which controls the overall growth trend of the probability of LIB explosion. Strength coefficient determines the resistance of LIB to the external stimulation. Wear coefficient controls the rate of rheology and mutation. The external forces, strength coefficient and wear coefficient were influenced by the factors, which lead to the LIB explosion. In order to analyze these factors, a fault tree of LIB explosion was built. The minimum cut sets and the structure importance degree coefficient of each basic event were calculated through Boolean algebra method. The collision is the most important factor that influences the LIB explosion. The protective measures for the safe use of LIB were proposed.

Published
2017

38. Design, fabrication, and characterization of the modular integrated exploding foil initiator system based on low temperature co-fired ceramic technology

Author

Jianhua Chen, Guofu Yin, Jiao Qingjie, Jiao Li, Yin Wang, Enyi Chu, Kewei Li, Honghai Tong, Mi zhou, and Wei Ren

Subjects
010302 applied physics, Materials science, business.industry, Flyback transformer, Metals and Alloys, High voltage, 02 engineering and technology, Spark gap, MOS-controlled thyristor, Modular design, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Chip, 01 natural sciences, Automotive engineering, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, 0103 physical sciences, Electrical and Electronic Engineering, Co-fired ceramic, 0210 nano-technology, business, Instrumentation, Voltage
Abstract

In this study, the flyback high-voltage conversion unit, capacitor discharge unit, and EFI chip of the exploding foil initiator (EFI) system were highly integrated using low temperature cofired ceramic technology and MEMS, forming a modular integrated system with boost, discharge, and firing functions. The modular integrated EFI system used the design idea of system in a package, selected chip-level or planar components, eliminating the need for connecting wires and reducing the volume of the EFI system to 5.67 cm3. Compared with the traditional EFI system, while analysis from the characterization showed that the integrated structure reduced the loop inductance of the system to 27 nH, which was 55 % lesser, it accelerated the flyer to 3800 m/s, which was 15.2 % faster. These accomplishments indicated that the energy utilization rate of the integrated system was higher. The input voltage of the system was reduced from traditionally high voltage of 1250 V to lower voltage of 24 V due to the integrated-system boost function. Simultaneously, the 5 V MOS controlled thyristor (MCT) chip was selected to replace 1800 V∼2500 V spark gap switch as the working voltage, thus making 5 V the switching voltage of the system. These changes made high safety operation of the system. Moreover, the system had used modular design and manufacturing to improve its reliability and obtained the characteristics of mass production.

Published
2020

39. Ignition characteristics of semiconductor bridge based on lead styphnate and lead azide charges under capacitor discharge conditions

Author

Ren Hui, Guili Yang, Qing Zhou, Hanjian Li, Jiao Qingjie, and Shujing Du

Subjects
Imagination, Chemical substance, Materials science, media_common.quotation_subject, 02 engineering and technology, 01 natural sciences, law.invention, chemistry.chemical_compound, Physics::Plasma Physics, law, 0103 physical sciences, Physics::Chemical Physics, Electrical and Electronic Engineering, Instrumentation, media_common, Lead styphnate, 010302 applied physics, business.industry, Metals and Alloys, Electrical engineering, Charge (physics), 021001 nanoscience & nanotechnology, Condensed Matter Physics, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, Ignition system, Minimum ignition energy, Semiconductor, chemistry, Atomic physics, 0210 nano-technology, business, Voltage
Abstract

Eight different sizes of semiconductor bridges and three kinds of charges, namely normal-lead styphnate (N-LS), lead azide (LA) and the double stacked charge (N-LS/LA), were selected to study the ignition characteristics of semiconductor bridge igniters under capacitor discharge conditions. The Neyer D-optimal Method was utilized in the experiments to explore the critical ignition voltages of the igniters. The relationships among the ignition voltage, current, resistance, and ignition time as well as other parameters of these igniters were analyzed. The results obtained were as follows: 1) The critical ignition voltage is positively proportional with the bridge area for the igniters possessing identical charge and ignition mechanism. 2) The ignition time and critical ignition voltage are related to the charges. The relationship of ignition time and charge following the short to long ranking is LA, N-LS/LA, and N-LS, but the relationship of critical ignition voltage and charge follows the opposite ranking. 3) The electroexploding ignition mechanism brings about shorter ignition time than electrothermal ignition mechanism for the igniters with identical charge, but the electroexploding ignition mechanism is accompanied by higher critical ignition voltage than the other.

Published
2016

Catalog

Books, media, physical & digital resources
See catalog results