Changes in the UN Manual of Tests and Criteria 6 th Revised Edition Section 38.3 Lithium Batteries

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1 Changes in the UN Manual of Tests and Criteria 6 th Revised Edition Section 38.3 Lithium Batteries This document is intended to provide a basic summary of the changes that will be included in the 6 th Revised Edition of the UN Manual of Tests and Criteria when it is released January 2012, specifically related to Section 38.3 for Lithium Batteries. Changes will go into effect on January 1, For more detailed information about your specific situation, please contact us. Most significant changes The following is a quick list of the most significant changes that will be included in the new revision of the UN Manual. Clarification of testing requirements for batteries including those constructed of already tested cells. Testing is required for all batteries, even if the cells they are constructed from have already been tested. Change in definition of battery to exclude single cell batteries. Single cell batteries will now be considered cells and tested as cells. Those with overcharge protection will additionally be required to pass the Overcharge Test (T7). The definition of a large cell is now the same for both primary and secondary cells (500g). Vibration testing for large batteries (over 12kg) has been modified. Cells and small batteries (less than 12kg) remains the same as previous revisions. T6 is now a Crush or Impact Test based on the size and shape of the cells involved. Samples sizes are different and very detailed test set-up requirements are provided for the impact testing portion. Scope and definitions The scope of the new document has added language to clarify the need to test all batteries, regardless of whether the cells used to construct the battery have been previously tested. Specifically, it states the following: All cell types shall be tested to T1 through T6 plus T8.

2 All non-rechargeable batteries (including those composed of previously tested cells) shall be tested to T1 through T5. All rechargeable batteries (including those composed of previously tested cells) shall be tested to T1 through T5 plus T7. All single cell batteries (which are now considered cells) with overcharge protection shall be subjected to T7. All component cells that are not transported separately shall be tested to T6 and T8 only. All component cells that are transported separately shall be tested as cells (T1 through T6 plus T8). As stated above, single cell batteries are now considered cells for the purposes of the revised test document. The definition of a battery was updated to reflect this. The new definition states that a battery consists of two or more cells. It also explicitly states in the definition that a single cell battery is considered a cell and shall be tested in accordance with the testing requirements for a cell. The scope section has also been updated to provide better clarification of when a cell or battery should be considered different for testing purposes from a type already tested. A 20% change in nominal energy (Watt-hours) or nominal voltage are now specifically defined as a different type. Additionally several examples of changes the might be considered different enough to affect the test results were added. These include, but are not limited to, Changes in materials used for the anode, cathode, separator or electrolyte. A change in the protective device used in a battery. A change in safety design (venting mechanisms). A change in the number or size of cells in a battery. A change in the connection mechanism of component cells. One of the main acceptance criteria for many of the tests in the UN Manual has always been no fire. However, until this point, no definition of fire was provided. Fire will now be defined as flames emitted from the test cell or battery. Additionally, the definition of leakage will be modified slightly and will refer to mass loss as a method of verifying leakage has occurred. With this, the mass loss limit table is also being modified and the new table is shown here. Mass M of cell or battery Mass loss limit M<1g 0.5% 1g M<75g 0.2%

3 M 75g 0.1% Several definitions were added to clarify test parameters that had previously been included in the test descriptions, but had never been fully defined as part of the standard. Most of these are harmonized with the IEC standards definitions. The added items include Nominal Energy, Nominal Voltage, Open Circuit Voltage and Rated Capacity. Finally, the definition of Large cell and Small cell were updated to be consistent for both primary and rechargeable cells. Large is any cell that has a gross mass of greater than 500g. Sample Sizes for Testing There are some changes to the sample sizes required for testing. The new samples size requirements are detailed in the following table. Test (by T Primary Rechargeable number) Cells Batteries Cells Batteries T1 T (small)/ 4 (large) T6 10 -* 5 -* T (small)/ 4 (large) T8 10 -* 20 -* Total (small)/ 8 (large) * For cells that will not be separately transported, component cells will only be required to be tested to T6 and T8. Test Procedures For T1 through T5, the specific requirement for no mass loss was removed. However, with the change in definition of leakage, mass loss is still verified and is still a criteria for passing the tests. T1 (Altitude Simulation) has had no changes made. In order to eliminate confusion noted in previous revisions, T2 (Temperature Cycling) was updated to clarify that a total of 10 cycles are to be completed. T3 (Vibration) has a change to the profile used for large batteries (over 12kg). Specifically, the peak acceleration value has been reduced from 8g n to 2g n. Cells and small batteries (less than 12kg) willcontinue to require the same profile as previous revisions. Mechanical Shock (T4) was not

4 modified. Short Circuit (T5) was slightly modified, to clarify that the acceptance criteria shall not be violated during the test as well as for 6 hours after the test has concluded. The Impact test of T6 has been significantly modified in the 6 th Edition of the UN Manual. It now includes 2 separate tests, Crush or Impact, based on the size and shape of the cells being tested. For cylindrical cells greater than 20mm in diameter, the impact portion of T6 is performed. For all other cells (prismatic, pouch, coin/button cells, and cylindrical cells less than 20mm) the required test is now a crush test. Revised Impact test procedure The new procedure for impact is very similar to the previous revision, but it provides much more detail on the set up, including the addition of tolerances on the units of measure required for the test set up. The diameter of the steel bar (15.8 ±0.1mm), the weight of the mass to be dropped (9.1±0.1kg) and the height of the drop (61±2.5cm) are not changed. The bar is now specifically required to be Type 316 stainless steel and have a length of at least 6cm, or the length of the longest dimension of the cell, whichever is greater. Additionally, the set-up of the falling mass is given more detail as well and must be dropped in a controlled manner using a near frictionless, vertical sliding track or channel. It is also specifically stated that the falling mass should be oriented 90 from the support surface of the cell under test. New Crush testing The crush test that has been added for all other cells, is different from the tests in UL 2054 and IEC The test is required to be performed by gradually crushing the cells between 2 flat surfaces with a speed of about 1.5cm/s at the first point of contact. The test is to continue until one of 3 outcomes is met. The force reaches 13±0.78kN, cell voltage drops by at least 100mV, or the cell is deformed by 50% or more for its original thickness. There is a 6-hour observation period, and the requirement is no disassembly, no fire and no external temperature greater than 170 C. The Overcharge (T7) and Forced Discharge (T8) tests procedures remain unchanged, however, the the pass/fail criteria was expanded to clarify that the criteria shall not be violated during the testing as well as for 7 days following the testing. CONTACT ENERGY ASSURANCE or VIST OUR WEBSITE FOR ADDITIONAL INFORMATION Energy Assurance LLC 5202 Belle Wood Court

5 Buford, GA The information contained in this summary/faq is intended to be general guidance and interpretations of the regulations as of the date completed. It does not constitute legal advice and cannot substitute for obtaining legal advice related to specifics of individual situations and products. While every effort has been taken to accurately represent the information within the various regulations contained herein, Energy Assurance does not guarantee its accuracy or completeness. Information may contain errors, omissions, or outdated information. Energy Assurance makes no representations or warranties as to the completeness, accuracy, or currency of the information provided in this FAQ.