The EUCAR Hazard Levels define the outcome of cell level safety testing. These levels are normally used to describe the outcome of tests such as overcharge as part of the cell specification.
| Description | Description | Classification Level & Effect |
|---|---|---|
| 0 | No effect | No effect. No loss of functionality |
| 1 | Passive protection activated | No defect; no leakage; no venting, fire or flame; no rupture; no explosion; no exothermic reaction or thermal runaway. Cell reversibly damaged. Repair of protection device needed. |
| 2 | Defect/ Damage | No leakage; no venting, fire or flame; no rupture; no explosion; no exothermic reaction or thermal runaway. Cell irreversibly damaged. Repair needed. |
| 3 | Leakage, mass change < 50% | No venting, fire or flame; no rupture; no explosion. Weight loss <50% of electrolyte weight (electrolyte = solvent + salt). |
| 4 | Venting, mass change ≥ 50% | No fire or flame; no rupture; no explosion. Weight loss ≥50% of electrolyte weight (electrolyte = solvent + salt). |
| 5 | Fire or flame | No rupture; no explosion (i.e. no flying parts). |
| 6 | Rupture | No explosion, but flying parts of the active mass. |
| 7 | Explosion | Explosion (i.e. disintegration of the cell). |
The EUCAR hazard levels are also used to describe the safety level for cell test chambers. However, you also need to understand the capacity of the cells being tested and the likely hazard level in order to determine if the chamber can contain the cell if it does fail. A large capacity cell being tested with a likely hazard level 4 result could create an overpressure in a small test chamber, the failure of the test chamber could itself endanger personnel.
References
- Battery requirements for future automotive applications – eucar
- Battery Safety and Abusive Battery Testing Overview – Sandia
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