Type

• The second generation iPod Shuffle uses a 3.7V, 100mAH lithium-ion polymer battery.
  
  

Capacity

• Apple advertises the battery life of the second generation iPod Shuffle to be up to 12 hours. In reviews, this claim has been shown to be correct.
  
  

Charge Time

• It takes approximately four hours to charge the second generation iPod Shuffle's battery to full. The battery reaches a charge level of 80 percent within the first two hours.
  
  

Checking Status

• Turn the unit off and on in quick succession to check the battery status. If the indicator flashes green, the battery is charged to 30 percent to 100 percent. An orange flash indicates a battery level of 10 percent to 30 percent, and a red flash indicates the battery is nearly dead.
  
  

Replacing

• To replace the battery, the unit must be carefully disassembled by prying off the lid, then pushing the logic board out. The battery has two wires that are soldered to the logic board. These must be removed and the new battery must be soldered in place.