Laptop Batteries

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Types of Batteries

OLPC is using two battery chemistry's from 2 vendors: NiMH, and LiFePo4 batteries. The LiFePo4 batteries allow charging at higher temperatures. The NiMH batteries cannot be charged above about 45 degrees C.

Our batteries vendors are Goldpeak and BYD.

GoldPeak provides both NiMH and LiFePo4 packs.
BYD provides only LiFePo4 packs.

Each chemistry and manufacturer have slightly different specifications.

GoldPeak NiMH

GoldPeak LiFePo4

Typical capacity: 2900 mAh
Minimum capacity: 2800 mAh
Operating Voltage Rage: 7.3V to 4V at 0.2C discharge current
Operating Temp Charge: 0 ~ +60°C
Operating Temp Discharge: -20 ~ +70°C
Standard charge rate: CC-CV .8C up to 7.3V
Max charge rate:1.5C(4200 mA)

BYD LiFePo4

Typical capacity: 3150 mAh
Minimum capacity: 3100 mAh
Operating Voltage Rage: 7.5V to 5V at 0.2C discharge current
Operating Temp Charge: -10 ~ +50°C
Operating Temp Discharge: -20 ~ +55°C
Max charge rate:1C(3150 mA)

Lifetime requirements for all batteries

Ambient Temperature:25°C
Number of Cycles:2000
Remaining Capacity after 2000 cycles:50%