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2015-06-15
Technical Paper
2015-01-2095
Wolfgang Hassler, Reinhard F.A. Puffing, Andreas Tramposch
Recent research on thermal ice protection of electrically heated restraining grids designed for applications in the environmental control system (ECS) of passenger aircraft is presented. The restraining grids consist of interlaced, electrically insulated wire (the topology of the grids is similar to that of tennis rackets) and are – in certain operation modes of the ECS – exposed to an airstream containing supercooled water droplets and/or ice particles. Heat is generated in the wire by an electric current, and the temperature of the wire is controlled with the aid of an electronic control system.
2015-04-24
WIP Standard
J1939DA
The J1939 Digital Annex The J1939 Digital Annex, introduced in August 2013, offers key J1939 technical data in an Electronic Spreadsheet that can be easily searched, sorted, and adapted to other formats. J1939DA contains all of the SPNs (parameters), PGNs (messages), and other J1939 data previously published in the SAE J1939 top level document. J1939DA also contains all of the SLOTs, Manufacturer ID Codes, NAME Functions, and Preferred Addresses previously published in the SAE J1939 top level and the J1939-71 document. J1939DA contains the complete technical details for all of the SPNs and PGNs previously published in the SAE J1939-71 document. It also includes the supporting descriptions and figures previously published in the SAE J1939-71 document. For other SPNs and PGNs which are published in a document other than SAE J1939-71, J1939DA lists only basic details along with a reference to the document that contains the complete technical details.
2015-04-17
WIP Standard
AS24509B
An Amendment corresponding to this standard is available at AS24509_A2
2015-04-15
WIP Standard
AS4805A
This SAE Aerospace Standard (AS) covers the general requirements for the design, manufacture, and test of Solid State Power Controllers (SSPCs) of both dc and ac ratings for use in electrical power systems. SSPCs conforming to this standard are intended for use in controlling the making and breaking of power circuits for electrically operated equipment and devices, and for providing overload and short-circuit protection.
2015-04-15
Standard
J2974_201504
This SAE Technical Information Report provides information on Automotive Battery Recycling. This document provides a compilation of current recycling definitions, technologies and flow sheets and their application to different battery chemistries.
2015-04-14
Collection
The success of HEV's, PHEV's & EV's is highly dependent on their batteries. This collection focuses on advanced battery technologies, including, but not limited to: advanced materials and cell chemistries, battery management systems and controls, modeling, testing, diagnosis and health monitoring, safety, reliability, durability, battery charging, battery economics/cost reduction, and system integration/optimization.
2015-04-14
Technical Paper
2015-01-1009
Cameron W. Tanner, Kenneth Twiggs, Tinghong Tao, David Bronfenbrenner, Yoshiaki Matsuzono, Shinichiro Otsuka, Yukio Suehiro, Hiroshi Koyama
Abstract Regulations that limit emissions of pollutants from gasoline-powered cars and trucks continue to tighten. More than 75% of emissions through an FTP-75 regulatory test are released in the first few seconds after cold-start. A factor that controls the time to catalytic light-off is the heat capacity of the catalytic converter substrate. Historically, substrates with thinner walls and lower heat capacity have been developed to improve cold-start performance. Another approach is to increase porosity of the substrate. A new material and process technology has been developed to significantly raise the porosity of thin wall substrates (2-3 mil) from 27-35% to 55% while maintaining strength. The heat capacity of the material is 30-38% lower than existing substrates. The reduction in substrate heat capacity enables faster thermal response and lower tailpipe emissions. The reliance on costly precious metals in the washcoat is demonstrated to be lessened.
2015-04-14
Technical Paper
2015-01-1197
Chao Chen, Franz Diwoky, Zoran Pavlovic, Johann Wurzenberger
This paper presents a system-level thermal model of a fluid-cooled Li-Ion battery module. The model is a reduced order model (ROM) identified by results from finite element analysis (FEA)/computational fluid dynamic (CFD) coupling simulation using the linear and time-invariant (LTI) method. The ROM consists of two LTI sub-systems: one of which describes the battery temperature response to a transient battery current, and the other of which takes into account of the battery temperature variation due to a heat flux induced by a varied inlet temperature of the battery cooling circuit. The thermal LTI model can be coupled to an electrical model to build a complete system-level battery ROM. Test examples show that the ROM is able to provide as accurate results as those from FEA/CFD coupling simulations.
2015-04-14
Technical Paper
2015-01-1189
Satyam Panchal, Scott Mathewson, Roydon Fraser, Richard Culham, Michael Fowler
Abstract A major challenge in the development of the next generation electric and hybrid electric vehicle (EV and HEV) technology is the control and management of heat generation and operating temperatures. Vehicle performance, reliability and ultimately consumer market adoption are integrally dependent on successful battery thermal management designs. In addition to this, crucial to thermal modeling is accurate thermo-physical property input. Therefore, to design a thermal management system and for thermal modeling, a designer must study the thermal characteristics of batteries. This work presents a purely experimental thermal characterization of thermo-physical properties of a lithium-ion battery utilizing a promising electrode material, LiFePO4, in a prismatic pouch configuration. In this research, the thermal resistance and corresponding thermal conductivity of prismatic battery materials is evaluated.
2015-04-14
Technical Paper
2015-01-1192
Xudong Xu, Xuezhe Wei, Hong Gao, Jiangong Zhu, Jing Yang, Yaofeng Liu
Abstract Lithium-ion battery charging strategy affects charging time of electric vehicles, energy efficiency of entire vehicle, service life and safety. This paper focuses on the lithium iron phosphate (LiFePO4) battery, based on the battery internal mechanism and the working conditions, taking charging time, effective full-charge capacity and charge energy efficiency as the evaluation indexes. Firstly, through a series of comparative experiments of the constant-current constant-voltage and the constant current charging strategy, the evaluation indexes variations in different temperatures and charging currents have been studied in the paper. By analyzing the respective characteristics of constant current charging phase and constant voltage charging phase in the whole charging process and their own contributions, we have found out the superiority of the constant current charging strategy.
2015-04-14
Technical Paper
2015-01-1191
Jiangong Zhu, Zechang Sun, Xuezhe Wei, Haifeng Dai
Abstract An electrochemical impedance spectroscopy battery model based on the porous electrode theory is used in the paper, which can comprehensively depict the internal state of the battery. The effect of battery key parameters (the radius of particle, electrochemical reaction rate constant, solid/electrolyte diffusion coefficient, conductivity) to the simulated impedance spectroscopy are discussed. Based on the EIS analysis, a lithium-ion battery optimized equivalent circuit model is built. The parameters in the equivalent circuit model have more clear physical meaning. The reliability of the optimized equivalent circuit model is verified by compared the model and experiments. The relationship between the external condition and internal resistance could be studied according to the optimized equivalent circuit model. Thus the internal process of the power battery is better understood.
2015-04-14
Journal Article
2015-01-1194
Zhenshi Wang, Xuezhe Wei, Haifeng Dai
Abstract Wireless charging system for vehicular power batteries is becoming more and more popular. As one of important issues, charging power regulation is indispensable for online control, especially when the distance or angle between chassis and ground changes. This paper proposes a novel power regulation method named Z-Source-Based Pulse-Amplitude-Modulation (ZSB-PAM), which has not been mentioned in the literatures yet. The ZSB-PAM employs a unique impedance network (two pairs of inductors and capacitors connected in X shape) to couple the cascaded H Bridge to the power source. By controlling the shoot-through state of H bridge, the input voltage to H bridge can be boosted, thus the transmitter current can be adjusted, and hence, charging current and power for batteries. A LCL-LCL resonant topology is adopted as the main transfer energy carrier, for it can work with a unity power factor and have the current source characteristic which is suitable for battery charging.
2015-04-14
Journal Article
2015-01-1193
Hiroto Maeyama, Toru Sukigara
Abstract Lithium-rich layered oxide, expressed as xLi2MnO3-(1-x) LiMO2 (M = Ni, Co, Mn, etc.), exhibits a high discharge capacity of 200 mAh/g or more and a high discharge voltage at a charge of 4.5 V or more. Some existing reports on cathode materials state that lithium-rich layered oxide is currently the most promising candidate as an active material for high-energy-density lithium-ion cells, but there are few reports on the degradation mechanism. Therefore, this study created a prototype cell using a lithium-rich layered cathode and a graphite anode, and analyzed the degradation mechanism due to charge and discharge. In order to investigate the causes of degradation, changes in the bulk structure and surface structure of the active material were analyzed using high-resolution X-ray diffraction (HRXRD), a transmission electron microscope (TEM), X-ray absorption fine structure (XAFS), and scanning electron microscope/energy dispersive X-ray spectroscopy (SEM-EDX).
2015-04-14
Technical Paper
2015-01-1196
Jeremy S. Neubauer, Eric Wood
Abstract Fast charging is attractive to battery electric vehicle (BEV) drivers for its ability to enable long-distance travel and to quickly recharge depleted batteries on short notice. However, such aggressive charging and the sustained vehicle operation that results could lead to excessive battery temperatures and degradation. Properly assessing the consequences of fast charging requires accounting for disparate cycling, heating, and aging of individual cells in large BEV packs when subjected to realistic travel patterns, usage of fast chargers, and climates over long durations (i.e., years). The U.S. Department of Energy's Vehicle Technologies Office has supported the National Renewable Energy Laboratory's development of BLAST-V-the Battery Lifetime Analysis and Simulation Tool for Vehicles-to create a tool capable of accounting for all of these factors. We present on the findings of applying this tool to realistic fast charge scenarios.
2015-04-14
Technical Paper
2015-01-1195
Kiyotaka Maeda, Masashi Takahashi
Abstract To verify the appropriateness of the vibration test conditions of ISO 12405, we performed tailoring to derive power spectrum densities and test durations as vibration test conditions. Vehicles used for tailoring included two electric vehicles and one plug-in hybrid electric vehicle. Those vehicles were equipped with accelerometers and were run on seven different road types at different speeds while data on the acceleration of the battery packs were recorded. The power spectrum densities for three axes that were derived from the obtained acceleration data were similar in form to the power spectrum densities of ISO 12405, and almost the same root mean square accelerations were obtained, confirming that they are appropriate. However, both experiments and theory suggest that the test duration for the Z-axis exceeds those of the X- and Y-axes.
2015-04-14
Journal Article
2015-01-1184
Satyam Panchal, Scott Mathewson, Roydon Fraser, Richard Culham, Michael Fowler
Abstract The performance, life cycle cost, and safety of electric and hybrid electric vehicles (EVs and HEVs) depend strongly on their energy storage system. Advanced batteries such as lithium-ion (Li-ion) polymer batteries are quite viable options for storing energy in EVs and HEVs. In addition, thermal management is essential for achieving the desired performance and life cycle from a particular battery. Therefore, to design a thermal management system, a designer must study the thermal characteristics of batteries. The thermal characteristics that are needed include the surface temperature distribution, heat flux, and the heat generation from batteries under various charge/discharge profiles. Therefore, in the first part of the research, surface temperature distribution from a lithium-ion pouch cell (20Ah capacity) is studied under different discharge rates of 1C, 2C, 3C, and 4C.
2015-04-14
Technical Paper
2015-01-1183
Padmanaban Dheenadhayalan, Anush Nair, Mithun Manalikandy, Anurag Reghu, Jacob John, V S Rani
Abstract Hybrid and electric vehicles are becoming increasingly popular these days owing to concerns over exhaustion of conventional fuel sources, pollution from combustion, as well as high carbon foot print of these fuels. Lithium-ion batteries are widely preferred as the source of power for hybrid and electric vehicles because of their high monomer voltage and high energy density. Accurate estimation of the State of Charge (SoC) of battery is crucial in the electric vehicle. It provides the information on the range of operation of the vehicle. It also ensures the safety and reliability of the battery unit. Accurate State of Charge estimation also enables more optimized battery pack design for the electric vehicle. Conventional methods for State of Charge estimation such as Coulomb counting and Open Circuit Voltage (OCV) measurement suffer from inaccuracies and is affected by noise during the vehicle operation.
2015-04-14
Technical Paper
2015-01-1181
Zhihong Jin, Zhenli Zhang, Timur Aliyev, Anthony Rick, Brian Sisk
Abstract Power limit estimation of a lithium-ion battery pack can be employed by a battery management system (BMS) to balance a variety of operational considerations, including optimization of pulse capability while avoiding damage and minimizing aging. Consideration of cell-to-cell performance variability of lithium-ion batteries is critical to correct estimation of the battery pack power limit as well as proper sizing of the individual cells in the battery. Further, understanding of cell variability is necessary to protect the cell and other system components (e.g., fuse and contactor, from over-current damage). In this work, we present the use of an equivalent circuit model for estimation of the power limit of lithium-ion battery packs by considering the individual cell variability under current or voltage constraints. We compare the power limit estimation by using individual cell characteristics compared to the estimate found using only max/min values of cell characteristics.
2015-04-14
Technical Paper
2015-01-1182
Mehrdad Mastali Majdabadi Kohneh, Ehsan Samadani, Siamak Farhad, Roydon Fraser, Michael Fowler
Abstract Lithium-ion batteries (LIBs) are one of the best candidates as energy storage systems for automobile applications due to their high power and energy densities. However, durability in comparison to other battery chemistries continues to be key factor in prevention of wide scale adoption by the automotive industry. In order to design more-durable, longer-life, batteries, reliable and predictive battery models are required. In this paper, an effective model for simulating full-size LIBs is employed that can predict the operating voltage of the cell and the distribution of variables such as electrochemical current generation and battery state of charge (SOC). This predictive ability is used to examine the effect of parameters such as current collector thickness and tab location for the purpose of reducing non-uniform voltage and current distribution in the cell. It is identified that reducing the non-uniformities can reduce the ageing effects and increase the battery durability.
2015-04-14
Journal Article
2015-01-1187
Nils Lohmann, Peter Haussmann, Patrick Wesskamp, Joachim Melbert, Thomas Musch
Abstract Battery aging is a main concern within hybrid and electrical cars. Determining the current state-of-health (SOH) of the battery on board of a vehicle is still a challenging task. Electrochemical Impedance Spectroscopy (EIS) is an established laboratory method for the characterization of electrochemical energy storages such as Lithium-Ion (Li-Ion) cells. EIS provides a lot of information about electrochemical processes and their change due to aging. Therefore it can be used to estimate the current SOH of a cell. Standard EIS methods require the excitation of the cell with a certain waveform for obtaining the impedance spectrum. This waveform can be a series of monofrequent sinusoidal signals or a time-domain current pulse with a dedicated Fourier spectrum. However, any form of dedicated perturbation is not generally applicable on board of an electric vehicle.
2015-04-14
Technical Paper
2015-01-1188
Seongjun Yun, SungJin Park, Daekwang Kim, Junyong Lee, Sejun Kim, Kwang-yeon Kim
Abstract The fuel economy of a vehicle can be improved by recuperating the kinetic energy when the vehicle is decelerated. However, if there is no electrical traction component, the recuperated energy can be used only by the other electrical systems of the vehicle. Thus, the fuel economy improvement can be maximized by balancing the recuperated energy and the consumed energy. Also, suitable alternator and battery management is required to maximize the fuel economy. This paper describes a design optimization process of the alternator and battery system equipped with recuperation control algorithms for a mid-sized sedan based on the fuel economy and system cost. A vehicle model using AVL Cruise is developed for cycle simulations and validated with experimental data. The validated model is used for the parametric study and design optimization of the alternator and battery systems with single and dual energy storage.
2015-04-14
Technical Paper
2015-01-1185
Brian Sisk, Timur Aliyev, Zhenli Zhang, Zhihong Jin, Negin Salami, Kem Obasih, Anthony Rick
Abstract Competitive engineering of battery packs for vehicle applications requires a careful alignment of function against vehicle manufacturer requirements. Traditional battery engineering practices focus on flow down of requirements from the top-level system requirements through to low-level components, meeting or exceeding each requirement at every level. This process can easily produce an over-engineered, cost-uncompetitive product. By integrating the key limiting factors of battery performance, we can directly compare battery capability to requirements. Here, we consider a power-oriented microhybrid battery system using coupled thermal and electrochemical modeling. We demonstrate that using dynamic resistance acquired from drive cycle characteristics can reduce the total size of the pack compared to typical static, fixed-duration resistance values.
2015-04-14
Technical Paper
2015-01-1186
Michael Safoutin, Jeff Cherry, Joseph McDonald, SoDuk Lee
Abstract While equivalent circuit modeling is an effective way to model the performance of automotive Li-ion batteries, in some applications it is more convenient to refer to round-trip energy efficiency. Energy efficiency of either cells or full packs is seldom documented by manufacturers in enough detail to provide an accurate impression of this metric over a range of operating conditions. The energy efficiency of a full battery pack may also be subject to more variables than would be represented by extrapolating results obtained from a single cell, and can be more demanding to measure in an accurate and consistent manner. Roundtrip energy efficiency of a 22.8-kWh A123 Li-ion (Lithium Iron Phosphate, LiFePO4) battery pack was measured by applying a fixed quantity of charge and discharge current between 0.2C and 2C rates and at SOCs between 10% and 90% at an average temperature of 23°C.
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