Battery Abuse Tolerance 147 Electrical abuse testing—short circuit, partial short circuit, overcharge, overdischarge, and AC exposure Electrochemical storage system vibration testing (United States Advanced Battery Consortium, 1999). Many of the automotive OEMs in the United States and in Europe use the either the FreedomCAR Hazard Severity Level or the EUCAR Hazard Levels that was developed by the European Council for Automotive Research and Development (EUCAR) (European Council for Automotive R&D, 2014) for evaluating the results of abuse testing ( Table 2 ).
These two rating systems are identical and the FreedomCAR system was based on the EUCAR system, so in essence these two groups have a common abuse testing severity rating system. In actual usage, most other global OEMs also recognize this system for identifying the level of failure. This rating system ranges from 0 where there is no effect on the cell or battery system to 7 which is identified as an explosion and/or rapid release of energy from the battery system. The optimal results of course would be a 0, but a level 1 or 2, passive protection has been activated and defect and damage has been identified but no venting, fire, rupture, or leakage Table 2:
EUCAR hazard ratings FreedomCAR Program Electrochemical Energy Storage Team (2003). Hazard Severity Level Description Classification Criteria and Effect 0 No effect No effect, no loss of functionality 1 Passive protection No damage or hazard, reversible loss of function. activated Replacement or resetting of protection device is sufficient to restore functionality 2 Defect/Damage No hazard but damage irreversible to RESS (Rechargeable Energy Storage System); replacement or repair needed 3 Minor leakage/venting Evidence of cell leakage or venting with RESS weight loss of 50% of electrolyte weight 5 Rupture Loss of mechanical integrity of the RESS container, resulting in a release of contents.
The kinetic energy of released material is not sufficient to cause physical damage external to the RESS 6 Fire or flame Ignition and sustained combustion of flammable gas or liquid (approximately more than 1 s). Sparks are not flames 7 Explosion Very fast release of energy sufficient to cause pressure waves and/or projectiles that may cause considerable structural and/or bodily damage, depending on the size of the RESS. The kinetic energy of flying debris from the RESS may be sufficient to cause damage as well.