Yeah as i said before, it is not a stock, original Samsung battery, it is a 3rd party battery, but again as i said it is a 2600 mAH battery as Samsung S4 stock battery.
Its name is "Deji Battery". After i made some research on internet, i found this battery and i bought it. There is also a dedicated thread on Xda about a member's battery tests from different battery brands, including this battery. It is an old thread, but if you search as "Deji Battery" on Xda, you will find some results..
What do you mean by the statement "he can't have used phone in normal way". If you mean playing hard games on phone, yes i don't play hard games on my phone, but i play light games. But except playing hard games, i do everything on my phone, that could be done with a phone: Surfing a lot on internet, on Tapatalk, using Whatsapp, listening to music on YouTube, messaging, making calls, receiving calls. I.e. what can be done with a phone, i do everything. Even, once the YouTube was open for 2 hours without break, i also reached 5 hours SOT.
BUT; if you mean making toasts with phone!? No, i don't! Or frying potato?! No, i don't! I don't do such those "hard" things with my phone! And lots of members knows me on Xda Forums, my all works/claims are trusted and tested. I don't like fake and fraudulent works! And i don't do!
BTW, i am not the only one who reaches 5-6 h SOT. Some other members (one of them is
@tuk1maar) also get this SOT. As i said in my previous post, if your battery is new, if you follow the correct steps, if you apply the correct methods and if you care about getting such a good SOT, it is POSSIBLE to get 5-6 h SOT.