Huge battery as the next trend in smartphones industry ?

Sometimes, it is funny how things are coming and going. When we got feature phones, we wanted them to become smaller and smaller.
When we got smartphones, we took the opposite direction quite quickly, the phones got bigger but we also wanted them to be good looking, fashion. It is a trend initiated by Apple and every others manufacturers followed and phones became thinner.

As phones reached the limit of thickness, now it is time for upgrading battery. A few years back, having a 1500 mAh battery, it was considered to be big. Nowadays, 2000 mAh is the minimum amount and you will need to monitor your phone usage in order to last the day especially if you have a 5 inch smartphone.

But things are evolving and are looking good so far. Big batteries are coming out and they already reached the 3000 mAh limit (this amount of energy last me 2 days with the XiaoMi Mi 2S) but it doesn't seem to stop there and we are looking to the 4000 mAh threshold.

The Boway U5 might be the first one to get to a Tablet like battery (the Nexus 7 has a 4000 mAh battery).
What's gonna be next ? We will be there for sure.