Proposals to UN transport regulation Samsung SDI Oct 2 nd 2013

 Concern - Wording for purpose of overcharge test can mislead to conduct the test even for battery without overcharge protection. - Purpose of Overcharge test is to check whether the protection works properly. And this is why the standard doesn’t requires the test on batteries without protection.  Proposal - Purpose : The test evaluates the overcharge protection works properly in a overcharge condition. Page 2 UN test condition proposal T7. Overcharge test

 Concern - Charging current “manufacturer recommended max continuous charge current x 2” can be severe comparing other int. standards. - And this results permissible max charge current to be lower.  Proposal - Overcharge test current to be Max charge current (x1) Page 3 TestConditionUNSeverity SAE J 2464 IEC T7Overcharge CurrentMax charge current X 2 1) > 1C rate Max VoltageMax charge voltage x 1.2≤ Maximum working voltage X2 Duration24hrs> 200% SOC (1hr) 1) Nominal charge current for EV/PHEV is 1C. Reducing the charge current for safety purpose makes charging duration longer. UN test condition proposal T7. Overcharge test

 Concern Battery with large cells will weigh more than a large cell. Test condition mismatch. For example, large cell in a small battery  Considerations Case1 : to simulate real car crash - No need to separate test condition for small and large batteries. Case2 : to simulate drop in manufacturing or logistics process. - Batteries composed of large cells will weigh more than a single large cell. Transportation process used to be limited by the weight of product. Transportation condition of heavy/large will not be severe than light/small one.  Proposal Batteries which is composed of large cells to be classified as Large battery. Page 4 TestConditionSmall Small vs Large Cell : 500g Battery : 12kg Large T4Mechanical shock Acceleration150gn50gn Duration6ms11ms Repeat3times/direction (totally 18times) UN test condition proposal T4. Mechanical shock test