The iPad Air 2 actually features a smaller battery capacity than its predecessor – not something we see often with technology. The original Air has a 8600 mAh battery unit, compared with the Air 2's 7340 mAh unit.
However, Apple still claim a 10-hour battery life for the Air 2, the same figure touted for the original iPad Air. This is in part due to the new M8 motion coprocessor, which increases power efficiency by directing tasks away from the main A8X CPU.
So while the battery won't last any longer, the battery life is supposedly no worse – and the lesser capacity helps make a thinner tablet.
We found this to be accurate in practice. A single charge, with WiFi or mobile data always on, lasted us about 2 days in real terms. Over the two days we aim to simulate everyday usage – so we watched a film on Netflix, wrote part of this review and streamed music via Spotify.
Certainly, if you use the iPad all day as your main device, it will not last so long. However, we cannot think of what you might be doing to drain it before the day is up, so it should last you at least one working day. Most users will find it lasting longer than this with less frequent usage.