Duracell Ni-MH manual Test Test Conditions Test Results

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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.

Forced-Discharge Test

The cell, after discharge,

(Voltage Reversal)

is over-discharged for 1.5

 

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 nickel-metal hydride cells and/or batteries tested under UL Standard 2054 test regimes.

*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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Contents Ni-MH Rechargeable Batteries Able of ContentsNi-MH Rechargeable Batteries 1 Introduction Active Components Positive and Negative Electrodes ElectrolyteCell Reactions Composition and Chemistry Cylindrical Cell Construction Basic Cell ConstructionPrismatic Cell Construction Battery ConstructionGeneral Characteristics Performance CharacteristicsPe rformance Characteristics Capacity Effect of Discharge Rate and TemperatureEnergy Density Constant Power Discharge Characteristics Perf ormance Char acteristicsPolarity Reversal During Overdischarge Performance Ch aracteristics Internal ImpedanceSelf-Discharge and Charge Retention Voltage Depression Memory Effect Performance Cha racteristicsGeneral Principles Charging Sealed Nickel-Metal Hydride BatteriesTechniques for Charge Control Charging Sealed Nickel-Metal Hydride Batt eriesCharging Sealed Nickel-Metal Hydride Batt eries co nt Temperature CutoffTimed Charge Voltage Plateau Zero ΔVDelta Temperature Cutoff Δtco Rate of Temperature Increase dT/dtCharging Methods Low-Rate Charge ≈12 hours Duracell’s Recommendation Three-Step Charge ProcedureQuick Charge ≈4 hours Fast Charge ≈1 hourTrickle Charge Thermal DevicesCycle Life Cycle and Battery LifeRecommended Permissible Battery LifeSafety Considerations Test Test Conditions Test Results Care and Handling Transportation Proper Use and Handling