Thursday, November 14, 2013
8:00 Registration, Exhibit Viewing/Poster Setup, Coffee and Pastries
8:50 Organizer’s Welcome and Opening Remarks
9:00 The Right Path to Safety: Chemistry or System?
Sam Jaffe, Senior Research Analyst, Navigant Research
Does a safe battery systems come from matching a safe chemistry for a particular application or from the safety engineering built into the integrated system? The answer is both, but this presentation will look at how different firms approach the safety issue (including A123, LG Chem and Tesla) and how their approaches have impacted costs and project success.
9:30 Battery Level Safety and Safety Validation
Larry J. Yount, President & CTO, LaunchPoint Energy and Power - LEAP LLC; and
Gary Houchin-Miller, Manager, Advanced Battery Systems, Power Solutions, Johnson Controls, Inc.
The safety of a Li-ion battery involved both chemistry and systems issues, including BMS peformance. A Safety Analyis might begin with the BMS, but must be broadened to address all battery issues, including the potential for cell-level thermal runaway.
10:00 Characteristics of Cells before a Thermal Runaway and How to Prevent it by a Better Battery Management System(tentative title)
Michael Pecht, PhD, PE, Director, Center of Advanced Life Cycle Engineering (CALCE) Electronics Products and Systems, Professor of Applied Mathematics, University of Maryland
James Post, Executive Product Manager, Director, Battery Condition Test International Ltd, Hong Kong
During the Battery Safety Conference in 2012, James Post discussed the concept of improved lithium-ion battery safety through thermal runaway precursor detection and a battery management system (BMS) that can mitigate catastrophic failure. This concept ultimately led to cooperation with the Center for Advanced Life Cycle Engineering (CALCE) at the University of Maryland and their battery group led by Professor Michael Pecht. (CALCE), who will address causes of thermal runaway and potential signatures that precede thermal runaway. James Post, Director of Battery Condition Test Intl. Ltd. will describe the functional specifications of the “Better BMS” and how the results will be validated.
10:30 Networking Refreshment Break, Exhibit/Poster Viewing
11:00 SENSOR: Embedded Fiber-optic Sensing Systems for Advanced Battery ManagementPeter Kiesel, PhD, Principal Scientist, and Ajay Raghavan, PhD, Senior Scientist, Palo Alto Research Center (PARC), a Xerox Company*
Under the ARPA-E AMPED program for advanced battery management systems, PARC and LG Chem Power are developing SENSOR (Smart Embedded Network of Sensors with an Optical Readout), an optically based smart monitoring system prototype targeting batteries for electric vehicles (EVs). The system will use fiber optic sensors embedded inside Lithium-ion battery cells to measure parameters indicative of cell state in conjunction with PARC's low-cost, compact wavelength-shift detection technology and intelligent algorithms to enable effective real-time performance management and optimized battery design. This talk will give an overview of the project, the underlying enabling technologies, and then cover some promising initial experimental results from the project, including internal cell signal data and state estimation using fiber optic sensors embedded in Li-ion pouch cells over charge-discharge cycles.
*In collaboration with: W.Sommer, A.Lochbaum, T.Staudt, B.Saha, S.Sahu, Bokkyu Choi, Jeffrey West, and Mohamed Alamgir
11:30 Safety of Large Li-Ion Battery Systems
Bart Mantels, Project Coordinator, VITO unit Energy Technology, Belgium
Until now, no systematic and comprehensive assessment of Li-Ion system safety exists for large grid-connected electric energy storage systems. This project developed and validated a framework for assessing the safety and reliability of large battery systems throughout the entire life cycle and at all levels of the system, building upon the generally accepted failure mode, effect analysis (FMEA) approach. This is a bottom-up analytical safety assessment that searches for potential failure modes, which is widely used in product development.
12:00 The Advancements of Battery Management Systems
Michael Worry, CEO, Nuvation; and
Jonathan P. Murray, Bloomy Energy SystemsToday’s batteries rely on an advanced Battery Management System (BMS) for optimal operation, and with properly engineered precision closed loop electronics, there is little excuse for the recent news catching the attention of the popular press. We will explore the complexity of a large format lithium pack in a custom electric race car (E.Rex) that has a top speed of 160mph and a 200+ mile range with 1000A+ current surges on a 350VDC battery pack. The design considerations for a large format BMS including monitoring the voltage and balancing hundreds of cells, redundant electronics and a fault-tolerant system design, along with the need for multiple levels of physical, electrical and software noise immunity will be discussed. The ability to safely, accurately, and repeatedly test and simulate standard and nonstandard pack events ensures the BMS critical functionality is always operating correctly. Having a common test platform throughput the design, validation, and manufacturing process of a BMS reduces production costs and improves system reliability.
12:30 Luncheon Sponsored by the Knowledge Foundation Membership Program
2:00 Lithium Ion Battery Memory, State of Health and State of Safety Assessments
Rachid Yazami, PhD, Professor, School of Materials Science and Engineering, Nanyang Technological University, SingaporeA new development in lithium ion battery characteristics revealed by thermodynamics methods is discovery of an ageing memory effect together with accurate assessments of the state of health (SOH) and state of safety (SOS). In fact lithium ion batteries retain a thermodynamics signature of the mode by which they aged such by cc-cv charge-discharge cycling, high temperature ageing and overcharge ageing. Thermodynamics also enable to clearly distinguish battery performance degradation during ageing arising for either anode, cathode or both. The SOH correlated well with entropy generation, which also goes with accelerating rate calorimetry data in connection with the battery SOS.
2:30 Electrochemical-Calorimetric Studies for The Determination of Heat Data of 40 Ah Lithium Ion Pouch Cells
Carlos Ziebert, PhD, Researcher, Institute for Applied Materials & Applied Materials Physics, Karlsruhe Institute of Technology, Germany*
Commercial 40Ah NMC Li-Ion pouch cells were cycled under isoperibolic and adiabatic conditions at rates up to 1C in an accelerating rate calorimeter to investigate performance and thermal behavior. Heat capacities, and total generated heat were measured after calibration using Al alloy dummy cells and the latter was separated into reversible and irreversible parts by potentiometric and current interruption technique. All these data are needed for thermal modeling and management.
*In collaboration with: E.Schuster, H.J.Seifert
3:00 Nail Penetration Tests of Commercial 18650 Type Lithium-Ion Cells and an Introduction of the BMBF Project SafeBatt
Jan Haetge, PhD, Research Scientist, MEET - Battery Research Centre, Westphalian Wilhelms University of Muenster, Germany
The presentation introduces nail penetration tests and the BMBF project SafeBatt. Nail penetration tests in adiabatic conditions were performed in an accelerating rate calorimeter (ARC) to generate internal short circuits in commercial 18650 lithium-ion cells. We tested a selection of cell chemistries with different states of charges (SoC). Through performing the measurements in adiabatic conditions, a detailed description of the temperature and pressure progress during the battery abuse is feasible. For future studies the ARC will be extended with further analytic instruments to perform online analytic measurements of the evolving gaseous products. The beacon project SafeBatt is funded by the German Federal Ministry of Education and Research (BMBF). The consortium consists of automotive manufacturers, supplying companies and academic institutions which cooperate to enhance the reliability and safety of lithium-ion batteries. The project focuses on improving the cell chemistry to increase the intrinsic safety of the battery and the implementation of sensors to monitor the safety relevant parameters inside the cell. Another topic is the optimization and standardizing of safety test procedures to validate safety concerns for state-of-the-art batteries and batteries with improved cell chemistry. MEET contributes with aging and safety tests of full cells and develops electrolytes with enhanced safety.
*In collaboration with: Mathias Reichert, Markus Börner, Falko Schappacher and Martin Winter
3:30 Networking Refreshment Break, Exhibit/Poster Viewing
4:00 An Easy Test Method to Differentiate Material System Safety Level
Deng-Tswen Shieh, PhD, Researcher, Dept of Lithium Battery Reliability Design, Material & Chemical Research Laboratories, Industrial Technology Research Institute, Taiwan R.O.C.
For nail penetration test the signal of voltage and temperature are important safe index. Up to now temperature detection is only capable of measuring surface of the battery, what happened on the point of short is keen to be understood. The special design with thermocouple embedded inside the tip of nail can help us detect real temperature reliably and do quantitative analysis. With such method and device, we test lithium-ion battery cell by introducing different nail shape and material under different test conditions. This test method has the capability to quantify the safety of battery to several levels and therefore guide the material system design quantitatively, which can be a good screening method to differentiate the safety level of battery and material system design.
4:30 Gaining Compliance to IEC 62133, 2nd Edition
Rich Byczek, Global Technical Lead for Electric Vehicle and Energy Storage, Intertek
For manufacturers of products using rechargeable batteries, the recent release of the second edition of IEC 62133 has introduced a number of revisions affecting their equipment. The primary changes affect lithium-ion cells and lithium-ion batteries, as well as nickel cadmium and nickel metal hydride cells and batteries. During this presentation, Intertek expert Rich Byczek will walk you step-by-step on how to come into compliance with the second edition of IEC 62133.
5:00 Exhibitor/Sponsor Showcase Presentations
Friday, November 15, 2013
8:00 Exhibit/Poster Viewing, Coffee and Pastries
9:00 Are Soft Short Tests Good Indicators of Internal Li-Ion Cell Defects?
Judith Jeevarajan, PhD, Battery Group Lead for Safety and Advanced Technology, NASA Johnson Space Center
Several methods exist that can predict whether a li-ion cell has an internal defect. Some of those are self-discharge tests at end of charge voltages, soft short tests at the end of discharge voltages, etc. It is also not clear if these tests are a good reflection of contaminants or other types of defects inside the cell. This paper will address the topic of whether there is a good method to detect internal cell defects in li-ion cells.
9:30 Development of an On-Demand Internal Short Circuit (NREL/NASA)
Matthew Keyser, Senior Engineer, Vehicles and Fuels Research, National Renewable Energy Laboratory
NREL has developed a device to test one of the most challenging failure mechanisms of lithium-ion (Li-ion) batteries—a battery internal short circuit. Many members of the technical community believe that this type of failure is caused by a latent flaw that results in a short circuit between electrodes during use. As electric car manufacturers turn to Li-ion batteries for energy storage, solving these safety issues becomes significantly more urgent. Due to the dormant nature of this flaw, battery manufacturers have found it difficult to precisely identify and study. NREL’s device introduces a latent flaw into a battery that may be activated to produce an internal short circuit. NREL uses the internal short circuit device to better understand the failure modes of Li-ion cells and to validate NREL’s abuse models. The device can be placed anywhere within the battery and can be used with both spirally wound and flat-plate cells containing any of the common Li-ion electrochemical systems. Producing a true internal short, the device is small compared to other shorting tools being developed by industry and does not rely on mechanically deforming the battery to activate the short, as do most of the other test methodologies. With the internal short in place, the battery can be used and cycled within normal operating conditions without activating the internal short device. This allows the battery to be aged prior to activation. The internal short produced by NREL’s device is consistent and is being developed as an analysis tool for battery manufacturers and other national laboratories as well as OEMs. This has broad-reaching applications as automakers bring electrified vehicles to market in larger numbers. NREL’s presentation will outline the differences in the voltage and temperature response between the four different types of internal shorts within a battery. We will also present results showing the difference between a foil to foil internal short when a shutdown and non-shutdown separator are used in an 18650 LiCoO2 cell.
10:00 Li-Ion Battery Safety Test for High Power Applications
JaeSik Chung, PhD, CTO, PCTest Engineering Laboratory
The adoption rate of LiB in high power applications has getting increased but the test information for its cell abuse and safety test was not reported much yet compare to that of small portable electronics. Besides, the operating conditions and usage environment of the high power application, especially power tool application, are much harsher than that of small portable electronics so that the test items and conditions for the high power application should be considered more carefully to simulate adequately the cell abuse conditions in connection with the devices. In this presentation, we will report the cell abuse safety testing (simulation in electrical, mechanical and thermal and thermal behaviors) for the high power application cells and compare the results between cell capacities and will discuss about those implications.
10:30 Networking Refreshment Break, Exhibit/Poster Viewing
11:00 Leclanché Highly Safe Titanate Lithium-Ion Batteries
Hilmi Buqa, PhD, R&D Manager, Leclanché SA, Switzerland
Advanced titanate-based cell technology entails the very high safety of Leclanché batteries; cells pass successfully the most severe safety tests, with impressively low level of reaction in response to abusive conditions. Moreover, Leclanché unique separator technology ensures unparalleled thermal stability of cell, adding extra safety in case of overheating or short-circuit. Innovative, unprecedented Leclanché water-based production process, applied to all electrodes, minimizes environmental impact of cell manufacturing, while improving performances.
*In collaboration with: Gianluca Deghenghi, Pierre Blanc
11:30 Enhanced Battery Safety through In-Situ Coatings
Christopher M. Lang, PhD, Group Lead – Energy Technologies, Physical Sciences Inc.
Safe, high performance cells are required to power next generation technologies. However, increasing energy densities of batteries tighten the required tolerances and the potential for catastrophic system failure. Physical Sciences Inc. has developed in-situ coatings that maintain the required high performance levels, while improving the abuse tolerance of cells. This presentation will discuss the results of these development efforts and highlight the performance benefits these technologies offer.
12:00 Battery State of Charge and State of Health Estimation Based on Electrochemical Models
Ryan Ahmed, PEng, R&D Engineer, Powertrain Engineering R&D Centre (PERDC), Ford Motor Company of Canada*
Recently, extensive research has been conducted in the field of battery management systems (BMS) due to increased interest in vehicles electrification. Parameters such as battery state of charge (SOC) and state of health (SOH) are of critical importance to ensure safety, reliability, and prolong the traction battery life. In order to accurately estimate these parameters, an accurate battery model along with robust estimation strategy is necessary. We propose a new aging battery model based on electrochemistry by varying the battery effective electrode volume. Based on a reduced-order of the developed model, a robust estimation strategy for SOC and SOH estimation has been effectively applied. The technique can be applied in real-time on board of a BMS.
*In collaboration with: McMaster University, Canada
12:30 Lunch on Your Own
2:00 Crashworthiness and Internal Short Modeling for Pouch and Cylindrical Lithium-Ion Cells
Elham Sahraei Esfahani, PhD, Researcher, and Tomasz Wierzbicki, PhD, Professor and Director, Impact and Crashworthiness Lab, Massachusetts Institute of TechnologyUse of lithium-ion in transportation brings new challenges in battery safety management. How much deformation or force a cell can tolerate before reaching internal short circuit is an important feature of the cell. Mechanical properties of a lithium ion cell depend on properties and proportions of sub-cell components (electrodes, separators, and electrolyte). To develop a finite element model of cell capable of simulating large deformation and crash resistance of cells, a practical modeling method is to consider the whole jelly roll as a homogenous material. This method is valid because the micro components are repeated periodically through the volume of jellyroll. We have used this assumption, and tested four types of lithium-ion cells of two form factors of cylindrical and pouch. The material properties of each cell type was then calibrated and used in developing finite element models. The models successfully predict load deformation and onset of electric short circuit in various loading scenarios.
2:30 Safer Batteries Through Predictive Simulation
John A. Turner, PhD, Group Leader, Computational Engineering & Energy Sciences Group, Oak Ridge National Laboratory
Modern battery packs store a significant amount of electrochemical energy that can pose a safety risk uncontrollably released. A comprehensive computational model for the battery configurations would enable us to expand the parameter space of adverse conditions and accident scenarios beyond what can be tested experimentally. We describe the development of computational models for simulating mechanical, electrochemical, and thermal responses of the prismatic and cylindrical battery cells under both normal and abnormal conditions. The models are based on finite element method (FEM) formulations of the partial differential equations describing the above physical phenomena. Algorithmic, implementation and computational details are described, and model calibration and comparison of the simulations with the ongoing battery safety experiments will be presented.
3:00 Networking Refreshment Break, Exhibit/Poster Viewing
3:30 In-Situ Gas Detection in Lithium-Ion Batteries
Christopher Hendrics, Reearcher, and Michael Pecht, PhD, PE, Director, Center of Advanced Life Cycle Engineering (CALCE) Electronics Products and Systems, Professor of Applied Mathematics, University of Maryland
While lithium-ion batteries are increasingly used in safety critical applications, the volatile nature of the most commonly used materials can lead to catastrophic failures. In particular, thermal runaway could lead to gas generation, fire, and explosion. The use of strain gauge measurements to detect external cell casing deformations during induced external short circuits is presented. The application of strain gauges for in-situ gas detection has demonstrated the potential to capture permanent deformations in the cell structure after undergoing a short circuit event that does not result in thermal runaway. This could potentially capture the effects of soft short circuits caused by metallic particle contamination or dendrite formation before they develop into more serious safety issues.
4:00 Real Time Monitoring and Characterizing of Lithium-Ion Batteries Aging
Cher Ming Tan, PhD, Associate Professor, and Leng Feng, Research Associate, Nanyang Technological University of Singapore; and TUM Create, Pte, Ltd., Singapore
Brief description (mini-abstract): We propose to use a recently developed electrochemistry based electrical model for Lithium-ion battery cell for the study of its ageing as the model is capable to take into account the various ageing causes. This is also an in-situtime-domain characterization method that enables us to monitor the information about the different ageing mechanisms on-line through its discharge curve alone. Through this information, better BMS can be designed to ensure a less degradation path for the battery pack, so that the life time of the battery pack can be extended.
4:30 New Metallic Contaminant Detection System Based on Faraday’s Law of Electromagnetic Induction
Saburo Tanaka, PhD, Prof, National University Corporation, Toyohashi University of Technology, Japan
For manufacturers producing Li-ion batteries or its materials, problems with metallic contaminants are critical issues. When contamination occurs, the manufacturer of the product suffers a great loss from recalling the tainted product. The lower detection limit for practical X-ray imaging is on the order of 1 mm. A detection system using a SQUID is a powerful tool for sensitive inspections. We previously proposed a direct detection system using multi-channel SQUIDs. In that system, an object with a contaminant is magnetized by a permanent magnet, and then a SQUID detects the remnant field of the contaminant. Because the detection width is defined by the size of the SQUID, eight-channel SQUIDs are required to inspect a specimen with a width of 65 mm, for example. This procedure is costly, and as a result, the system has not been widely used in the field. To circumvent this problem, we propose an indirect high-Tc SQUID magnetic metallic contaminant detector combined with a coil and magnet. The principle of the system is based on Faraday’s law of electromagnetic induction. The detection section consists of permanent magnets and copper-wound pickup coils. The signal is magnetically transferred to a SQUID magnetometer. The differential pickup coil successfully measures an iron test piece with a size of 40 µm when the test piece was moved with a speed of 100 m/min. The advantage of this indirect detection method is that the detection width is wider than the previous SQUID direct detection method. The detector is able to detect a 50-µm iron test piece within a range of 20 mm with an SNR greater than 5. Since two coils are differentially connected in series, a detection width of 40 mm (2 - 20 mm) per channel is realized and two SQUIDs are sufficient for an inspection width of 65 mm. This is a great advantage compared to the direct detection system, which requires eight-channel SQUIDs to inspect an object with a width of 65 mm. This detection method is effective for the inspection of non-metallic materials such as the plastic film separator of a Li-ion battery. If the criterion of the detection size is moderated and 100 um, the SQUID sensor can be replaced by a low cost flux gate magnetic sensor. In the case, the cost of the system is dramatically reduced. In my talk, the evaluation results of the indirect contaminant detection system using a flux gate magnetic sensor will be also discussed.
5:00 Selected Oral Poster Highlights
5:15 Concluding Remarks, End of Conference