Should the MacBook Air have the same amount of charge as its stated capacity when 'Full Charged'?

Question

The following is an extract from System Information (under power):

 Charge Information:
  Charge Remaining (mAh):   6517
  Fully Charged:    Yes
  Charging: No
  Full Charge Capacity (mAh):   6690

Is this simply an example of the charger not topping up the battery to conserve cycles, poorly calibrated battery or an issue with my machine's battery?

Answer 1

"Fully charged" does not mean exactly 100%, but somewhere between 95% (or even less) and 100%. Obviously it is better for battery life if the battery is not immediately loaded after a small percentage of charge was consumed, if your MacBook is connected to the charger. So you do not have an issue with your battery.