Committee of experts on the transport of dangerous goods and on the globally harmonized system of classification
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UN/SCETDG/COMMITTEE OF EXPERTS ON THE TRANSPORT OF DANGEROUS GOODS AND ON THE GLOBALLY HARMONIZED SYSTEM OF CLASSIFICATION AND LABELLING OF CHEMICALS Working Group on the Transport of Lithium Batteries 4rd Session Washington, DC, May 2010 Item 1 of the provisional agenda LISTING, CLASSIFICATION AND PACKING Testing of Large Lithium Batteries and Lithium Battery Assemblies Transmitted by the Council on the Safe Transportation of Hazardous Articles (COSTHA) Introduction1. Among COSTHA’s membership is a group identified as the North American Automotive HAZMAT Action Committee (NAAHAC). Participants in this committee include 12 automobile manufacturers from around the world but operate in the United States. Additionally, COSTHA counts five (5) additional members who are direct suppliers to the automotive industry, providing numerous materials and devices for production support. 2. The Sub-Committee has recognized the need to review the UN Manual of Tests and Criteria, specifically Section 38.3 as they relate to the transport of large lithium batteries and assemblies. COSTHA supports the efforts of the Sub-Committee in this endeavour and would like to present data to further the discussion. Discussion 3. The concern over the testing in large format lithium ion batteries was discussed at length at the UN Informal Working Group on Batteries held 11 November to 13 November 2008. During this meeting, Delphi, a COSTHA member organization, provided a presentation detailing the concerns facing the gasoline-electric hybrid vehicle, hydrogen fuel cell hybrid-electric vehicle, and pure battery electric vehicle manufacturers and suppliers with regards to the testing of these “large” batteries. Specifically, the UN Tests T3 and T4 were identified as posing significant design issues for the battery manufacturers. 4. While the concerns over the T3 test have been addressed by previous COSTHA presentations, the issue of T4 has not been discussed since the 1st UN Working Group on Lithium Batteries in November, 2008. Since that time, automotive manufacturers have had the opportunity to test their battery assemblies against both automotive vehicle safety standards and UN lithium battery testing standards (Section 38.3). Results of these tests suggest additional review must be conducted regarding the T4 test, particularly as it applies to large format batteries. 5. Test 4 currently requires cells and batteries to be subjected to a half-sine shock of peak acceleration of 150 gn and a pulse duration of 6 milliseconds. The shock test includes 3 shocks in the positive and 3 shocks in the negative direction in 3 mutually perpendicular mounting positions of the cell or battery. For large format batteries (gross mass greater than 12 kg), the peak acceleration shall be 50 gn and a pulse duration of 11 milliseconds. 6. Gasoline-hybrid vehicle battery assemblies typically range today between 14 kg and 80 kg with full-electric vehicle batteries often exceeding 100 kg mass. Their capacity is typically 300 Wh to 2,500 Wh for hybrid batteries and in excess of 5,000 Wh for full-electric vehicle batteries, with Plug-In Hybrid Electric Vehicle (PHEV) batteries occupying any capacity and mass in between. Applied Forces for Different Masses 7. Current Test 4 force and acceleration conditions are inappropriate for these hybrid or electric vehicle (HEV) battery assemblies as well as other large format batteries, and most importantly, the forces required for HEV battery assemblies during the testing are well beyond any forces that would be encountered during transport. 8. The T4 Shock Test is an impact test, with the governing equation: F * dt = m * dv Where: F = applied force measured in Newtons (N) dt = time the force is applied (s) m = mass of the test part (kg) dv = change in velocity of the test part while the force is applied (m/s) And further note that momentum p = m * v (kg-m/s). 9. When the formula is shown in this form, it is apparent that one can vary the force applied and the time that the force is applied to achieve a desired change in momentum. It is also apparent that both the acceleration and the test time are fixed, this results in varying the force on the test mass. However, larger batteries may not actually be subjected to higher impact forces in transportation. 10. When we look at the current UN 38.3 T4 graph of Force vs mass, there are three implausibilities that arise: 
11. When viewed as a Force vs Mass Curve, three implausibilities arise: It is implausible that there should be a discontinuity at 12kg, where the force applied to an 11.99kg battery should be 3x the force applied to a 12.00kg battery. It is implausible that more massive articles in transportation actually do experience higher forces For instance, the cargo bed of an aircraft might not be capable of imparting a 50,000N+ force on a 100kg+ large battery. It is implausible that batteries greater in mass than approximately 120kg (6200Wh) would pose a lesser risk in transportation than smaller batteries, and should be exempt from testing. 12. To provide a comparison and an understanding that these forces are very large and generally are not generated during transportation, we compare this to the forces generated in an automobile collision. In a front offset collision (a very punishing crash test for an automobile), the force required to stop a 1600 kg vehicle that crashes into a brick wall from 30 miles per hour with 1m of deformation on the vehicle is approximately 143kN. Framing the discussion in this nature, it is unreasonable to expect that forces on the order of 50kN would be experienced by a 100kg battery during transportation (Table 3). Directory: wp-content -> uploads uploads -> 587 Return function, r i(X) r i(0) r i(1) r i(2) r i(3) 1 0 2 4 6 Thermal Station, I 2 0 1 5 6 3 0 3 5 6 10 uploads -> The Case Against the nypd’s Quota-Driven ‘Broken Windows’ Policing What Is It? uploads -> For want of a nail uploads -> Police Militarization uploads -> Stop Militarizing Law Enforcement Act of 2014 uploads -> 2017 afoCo Landmark Scholarship Program uploads -> Instructions for the Preparation of Camera-Ready Contributions to the Conference Proceedings uploads -> Medical Radiography Program uploads -> Ihbb asian Championships 2014 middle school bowl Round 4 First Quarter uploads -> Ihbb european Championships 2014 Bowl Round 4 First Quarter Download 125.95 Kb. Share with your friends:
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