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 Large Format Lithium Batteries 3rd Session Washington, D.C. USA, September 2014 LISTING, CLASSIFICATION AND PACKING
1. 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 of large format lithium ion batteries was discussed at length during the UN Informal Working Group on Batteries held in 2008-2010. During this meeting, COSTHA and member organizations provided presentations 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 Test T4 was identified as posing significant design issues for the battery manufacturers yet was not modified as a result of the previous Working Group conclusions. 4. In May of 2010, COSTHA presented a paper discussing the physics of the T.4. The paper was well received but no formal proposals resulted directly from the effort. This document recounts much of the technical data presented in that paper. However, based on discussions since May 2010, including discussions at the first session of the UN Working Group on the Transport of Large Format Lithium Batteries, COSTHA has been proposing changes to the T.4 test based upon a sliding scale of mass vs. acceleration. This concept was discussed and development was encouraged at the October, 2013 UN Lithium Battery Working Group meeting held in Washington, D.C. 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 a total of 18 shocks per battery. For large format batteries (mass greater than 12 kg), the peak acceleration shall be 50 gn and a pulse duration of 11 milliseconds. 6. Gasoline-hybrid vehicle traction batteries 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 6,200 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 = m*a This formula can be further manipulated: F = m * dv/dt 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) a = acceleration (m/s2)
9. It is apparent that both the maximum acceleration and mass 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. A graph of the current UN 38.3 T4 graph of Force vs mass is shown in Figure 1: 
Figure 1 Curent UN T4 Test Forces 11. Concerns about this curve include the following: The force necessary to test a large lithium ion battery is significantly higher than for smaller batteries. As shown in previous COSTHA presentations, the force applied to larger lithium batteries is not proportional. i.e. 10x mass results in >10x Force. Is it rational to test an 11.99 kg battery at 17k N (150 gn) and a 12.01 kg battery at ~6k N (50 gn)? 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 284.47 Kb. Share with your friends:
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