iPad does not charge beyond 80%

Do you leave your iPad connected to its Power Adapter for extended periods? If so, this is not of itself an issue - as the iPad will optimally manage battery charging. When connected to a Power Adapter for an extended period of time, such as when used in Kiosk or PoS (Point if Sale) applications, iPad will change its charge management strategy - and reduce the maximum battery charge level to about 80% of maximum capacity. This strategy is intended to extend the life of the battery by reducing chemical ageing that occurs when the battery is continuously maintained 100% charge. As soon as a “normal” charge/discharge pattern is resumed, charge to full capacity is restored.

More information about iPad’s battery management can be found here:

About iPad and iPhone Charge Management Feature – Apple Support

Are you letting your new iPad Air 4 charge long enough?

Usually, the last 15%-20% of charging to 100% takes longer than from 5-10% to 80%

The slower charging from 80% to 100% is to help preserve the life of the battery and to prevent any overcharging issues, by slowing down the charging cycle during the last 15%-20% of battery charging

If yiu are using the supplied Apple 20W power/charging adapter, it takes approx. between 2-1/2 to 3 hours for your new iPad Air 4 to fully charge to 100%