battery health

My iPad Air (Model MD785X/A) battles to get through a day without half of the time on the charger. I suspect the battery is getting a bit old. ;) Is it possible to fit a replacement battery?

Apple took us off guard on Thursday by releasing iOS 11.3, the latest major update to iOS 11. Among the many new features included in the update are the long-awaited “Battery Health” feature that arose after the whole performance-throttling furore of the past few months, and which will notify...