The batteries that currently sit behind smartphones are always under heavy scrutiny, with the minimum expectation of a day's worth of use.
In order to make sure that this target is achieved, Sony has given the Xperia M2 a 2300mAh battery. This sits within the sealed chassis so there is no way to swap out the battery when it dies.
This shouldn't prove too much of a problem though given the availability of portable power packs.
Sony appears to have been very generous with its battery here, given that the Moto G ships with a 2070mAh battery and the EE Kestrel with only 2000mAh. The Samsung Galaxy Ace 3 lags even further behind at only 1800mAh for the LTE version.
I am pleased to report that the battery held up very well during day-to-day use. Due to the novelty of the camera app I found that I kept pulling the Xperia M2 out of my pocket to show people and snap silly photos.
The Sony Xperia M2 was also connected to rather patchy Wi-Fi signal meaning that the drain was also a little higher, yet I was able to make it through a full day of work with about 35% left.
This is backed up further by our battery tests of mobile gaming and video watching, two of the biggest battery drains.
Putting the Xperia M2 through its paces during gaming gave only a 2% drain after 10 minutes. This was tested with both the BBC's Top Gear Race the Stig game (a game based heavily on Subway Surfers or Sonic Dash), as well as running the more traditional Temple Run 2.
This is in stark comparison to the EE Kestrel. Given that the Kestrel has the same resolution screen, the same powered internals and a relatively similar battery size it was shocking to see that the Sony managed to outperform the Huawei built handset.
Even running the standard TechRadar battery test of a 90-minute HD video (run at full brightness of 320 LUX) showed some really impressive results. Where the Kestrel drained by 30% and the Moto G by 33%, the Xperia M2 lost a mere 17% battery life.
Sony helps push the battery even further with its quick toggles in the notifications bar, as well as its stamina mode found within the settings menu.