Ni-MH Rechargeable Batteries
Safety Considerations
(cont.)
Table 8.0.1
Test | Test Conditions | Test Results |
Flat Plate Crush Test | Cell is crushed between | No explosion, sparks, or flames. |
| two flat surfaces. |
|
|
|
|
Impact Test | A 20 lb. weight is dropped from |
| height of 2 feet on cell. |
No explosion, sparks, or flames.
Short Circuit Test* | Sample is shorted until discharged. |
| Test conducted at 20°C and |
| 60°C (68°F and 140°F). |
No evidence of venting, leakage, bulging or other visible changes on individual cells. Maximum case temperature was
129°C (264°F). In batteries, safety devices operated, protecting battery from external short. Maximum battery case temperature was within 5°C (41°F) of ambient.
The cell, after discharge, | |
(Voltage Reversal) | is |
| times rated capacity. |
No venting, leakage, fire or explosion on test conducted at C/3 discharge rate.
Abnormal Charge | Cell is charged for 2.5 |
Test | times rated capacity. |
No venting, leakage, fire or explosion on test conducted at C/3 charge rate.
Abusive Overcharge | Sample is charged by |
Test* | power supply up to |
| 200 watts until sample |
| vents or explodes. |
Individual cells vented. No explosion or fire. Maximum temperature on cell case was
200°C (392°F). In batteries, safety devices caused charging circuit to open periodically, protecting battery as designed. Maximum battery case temperature was within 25°C (77°F) of ambient.
Heat Test | The cell is heated in an oven to |
| 150°C (302°F). |
No damage to cells; no bulging, venting, fire or explosion.
Fire Exposure Test* | Sample is heated by a burner |
| fueled with methane. |
Cells and batteries vented without exploding. No significant flaming or spark. No projectiles.
Table 8.0.1 Results of DURACELL
*Note: These tests were conducted on both individual cells and batteries. Tests not marked with an asterisk were conducted on individual cells only, as deemed adequate by UL to demonstrate safety of both cells and batteries.
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