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Evaluation of External Short-Circuit Safety of NCM/C Li-Ion Power Battery under Different State of Health

CATARC-Chunjing Lin, Fang Wang, Bin Fan
Harbin Institute of Technology-Peixia Yang
  • Technical Paper
  • 2020-01-0454
To be published on 2020-04-14 by SAE International in United States
With the increasing frequency of fire incidents of electric vehicles, the safety of power batteries has attracted more and more attention. At present, the research on the safety of power batteries is mainly focused on fresh batteries. As the state of health of batteries deepens, how the safety of the battery evolves is not clear enough so far. This paper analyzes the external short-circuit safety of a NCM/C rectangular battery under different state of charges. The results show that when the cycle number is less than 800, the maximum temperature of the battery during short-circuit is below 130 °C. The main failure mode of the battery is bulging in volume or opening of the explosion-proof valve and there is no obvious regularity between the failure mode with the cycle life. However, when the cycle number reaches 1000, the battery goes into thermal runaway during the safety test. In specific, the explosion-proof valve opens, and a large amount of smoke is sprayed, and the surface temperature of the battery reaches 350 °C with obvious burn marks.…
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An Adaptive Neuro-Fuzzy Inference System (ANFIS) Based Model for the Temperature Prediction of Lithium-Ion Power Batteries

SAE International Journal of Passenger Cars - Electronic and Electrical Systems

China Automotive Technology and Research Center Co., Ltd. (CATARC)-Bin Fan, Chunjing Lin, Fang Wang, Shiqiang Liu, Lei Liu
Tongji University-Sichuan Xu
  • Journal Article
  • 07-12-01-0001
Published 2018-08-14 by SAE International in United States
Li-ion batteries have been widely applied in the areas of personal electronic devices, stationary energy storage system and electric vehicles due to their high energy/power density, low self-discharge rate and long cycle life etc. For the better designs of both the battery cells and their thermal management systems, various numerical approaches have been proposed to investigate the thermal performance of power batteries. Without the requirement of detailed physical and thermal parameters of batteries, this article proposed a data-driven model using the adaptive neuro-fuzzy inference system (ANFIS) to predict the battery temperature with the inputs of ambient temperature, current and state of charge. Thermal response of a Li-ion battery module was experimentally evaluated under various conditions (i.e. ambient temperature of 0, 5, 10, 15 and 20 °C, and current rate of C/2, 1C and 2C) to acquire the necessary data sets for model development and validation. A Sugeno-type ANFIS model was tuned using the obtained data. The numbers of input membership functions (MFs) representing the three input parameters of this model are 1, 2, 3, respectively.…
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Co-Simulation and Analysis on Aerodynamic Noise at the Engine Inlet

Tianjin University-Ming Qin, Wenzhi Gao, Lei Liu, Pan Zhang, Yong Li, Lifeng Wei
Published 2018-04-03 by SAE International in United States
As the intake noise is a major contributing factor to automotive passenger compartment noise levels, it has received much more attention than before. Because the plastic manifolds could induce and transmit more noise owing to their lighter weight, aerodynamic noise has become a more serious problem in plastic manifolds than in conventional aluminum-made manifolds. Due to the complexity of aerodynamic noise of the intake system, it is difficult to predict the noise precisely, especially for the part whose frequency is higher than 1000 Hz. This paper introduces a new co-simulation method to simulate the aerodynamic noise at the engine inlet. With the coupled simulation between two programs, GT-Power and Fluent, it could simulate the gas flow inside the engine intake system, under the actual running condition of engine. Transient noise source data could be stored for every time step during the coupling process and then should be exported into LMS Virtual.Lab, used as boundary conditions for the calculating of aerodynamic noise at the engine inlet. The coupled simulation results are further corrected to eliminate the effects…
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The Application and Optimization of EGR-LNT Synergetic Control System on Lean-burn Gasoline Engine

Tianjin University-Lei Liu, Zhijun Li, Boxi Shen
Published 2015-04-14 by SAE International in United States
Ensuring lower emissions and better economy (fuel economy and after-treatment economy) simultaneously is the pursuit of future engines. An EGR-LNT synergetic control system was applied to a modified lean-burn CA3GA2 gasoline engine. Results showed that the synergetic control system can achieve a better NOx reduction than sole EGR and sole LNT within a proper range of upstream EGR rate and without the penalty in fuel consumption. It also has the potential to save costly noble metals in LNT, but excessive or deficient upstream EGR would make the synergetic control system inefficiency.In order to guarantee the objectivity of the effect of EGR-LNT synergetic control system on NOx reduction, another modified lean-burn CA4GA5 gasoline engine was additionally tested. Results verified that proper range of upstream EGR rate in EGR-LNT synergetic control system and showed that, less upstream EGR could not lower the NOx generated from in-cylinder effectively, while more upstream EGR would deteriorate NOx conversion efficiency of downstream LNT, either of these two cases will affect the final application effect of EGR-LNT synergetic control system.The emissions of…
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Analytical Solutions of Resilience Based on Tri-Parameters Constitutive Model under Different Cold-Forming Cases

SAE International Journal of Materials and Manufacturing

Shanghai Aero Plane Mfg Co., Ltd.-Lei Liu, Zhiheng Yang, Bo Song
Tongji Univ.-Zhengwei Fan, Jianhua Jiang
  • Journal Article
  • 2014-01-0374
Published 2014-04-01 by SAE International in United States
Ti-alloy sheet is a high-modulus elastic-plastic material, about which the resilience in the cold-forming process is quite difficult to control. As a matter of fact, the procedure of cold-forming is composed of many cases such as tensile case and bending case. An expression of ultimate radius for bending-curvature is obtained based on tri-parameters elastic-plastic constitutive model. By classifying the cold-forming process, some typical cases of cold-forming are presented in this paper, and analytical solutions with a high precision of resilience for high-modulus elastic-plastic material such as Ti-alloy sheet under the different typical cases are obtained in this paper. The accurate analytical solutions of resilience for high-modulus elastic-plastic material presented in this paper will contribute to cold-forming process both in the mould-designing and optimizing of cold-forming procedure.
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Effect of Nugget Size on Tensile and Fatigue Strength of Spot Welded AZ31 Magnesium Alloy

Univ of Waterloo-Grzegorz Glinka
Univ. of Waterloo-Behzad Behravesh, Lei Liu, Hamid Jahed, Stephen Lambert, Norman Zhou
Published 2010-04-12 by SAE International in United States
Interest in magnesium, as the lightest engineering metal, has increased in the automotive industry as a result of requirements for lighter and cleaner vehicles. Resistance spot welding (RSW) is already the predominant mode of fabrication in this industry, and the fatigue of spot welded magnesium sheet must be studied. In this study, the tensile and fatigue strength of resistance spot welded AZ31 Mg alloy was studied. Three sets of tensile shear spot welded specimens were prepared with different welding parameters to achieve different nugget sizes. Metallographic examination revealed grain size changes from the base material (BM) to heat affected zone (HAZ) to the fusion zone (FZ). Monotonic tensile and fatigue tests were conducted and the effect of nugget size on tensile shear and fatigue strength was discussed. Modes of failure in each set of specimens under tensile and cyclic loading were examined and compared with those in steel and aluminum spot welds which are the most common materials in the automotive industry. Microstructural features of the fracture surface were studied.
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An Experimental Study of the Chassis Vibration Transmissibility Applying a Spectral-based Inverse Substructuring Technique

University of Alabama-Lei Liu
University of Cincinnati-Teik C. Lim
Published 2005-05-16 by SAE International in United States
A proposed multi-coordinate spectral-based inverse substructuring approach is applied experimentally to examine the vibration transmissibility through chassis mounts. In this formulation, the vehicle system is partitioned into two substructures. One substructure comprises of the chassis and suspension, while the second one is the body structure and other attached components. The approach yields the free substructure dynamic characteristics that are extracted from the measured coupled system response spectra. The resultant free substructure transfer functions are verified by comparison of the re-synthesized results to the actual vehicle system measurements. A real life vehicle setup is utilized to demonstrate the salient features and capabilities of this approach, which includes the ability to compute the main structure-borne paths, dynamic interactions between the chassis and body, and interior noise and vibration response.
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Application of FRF-Based Inverse Substructuring Analysis to Vehicle NVH Problems

University of Alabama-Lei Liu
University of Cincinnati-Teik C. Lim
Published 2003-05-05 by SAE International in United States
A multi-coordinate FRF-based inverse substructuring approach is proposed to partition a vehicle system into two or more substructures, which are coupled at discrete interface points. The joint and free substructure dynamic characteristics are then extracted from the coupled system response spectra. Depending on the actual form of the structural coupling terms, three forms of the coupling matrix are assumed here. The most general one constitutes the non-diagonal form, and the other two simpler cases are the block-diagonal and purely diagonal representations that can be used to simplify testing process and overcome computational problems. The paper is focused on the investigation of the durability of these three formulations when the input FRFs are noise contaminated. A finite element model of a simplified vehicle system is used as the case study. In general, simulation results show that the non-diagonal and block-diagonal formulations are very sensitive to the input noise, while the purely diagonal formulation is much less noise sensitive. This is because the matrix inversion process involved in the non-diagonal and block-diagonal formulations cause the magnification of…
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