Brand new iPad Air 2 only charging to 99%?
Memory effect has nothing to do with it. Calibration of modern batteries is all about the microprocessor control circuit for the battery being accurate. This affects charging and reporting.
Straight from Apple on 6-25-10
iBook, MacBook Pro, MacBook, PowerBook, MacBook Air
The battery has an internal microprocessor that provides an estimate of the amount of energy in the battery as it charges and discharges. The battery needs to be recalibrated from time to time to keep the onscreen battery time and percent display accurate and to keep the battery operating at maximum efficiency. You should perform this procedure when you first use your computer and then every few months after that. If you normally leave your Apple portable computer connected to AC power and very rarely use it on battery power you may want to perform this process once a month. The website www.apple.com/batteries has more helpful information regarding batteries and offers an iCal calendar to remind you to calibrate your battery.