Why did my new s7 edge battery go from 95 to 40% instantly at some point overnight?

[AC Question]

Hi,

so i literally got my new s7 edge just over a day ago. on the first day the phone battery was amazing. i believe i got over 4 hours screen on time with still 40% remaining. then, i charged the phone to 95% before i went to sleep. i left the phone on my desk, turned the wifi off as well as LTE.

now, i woke up in the morning realizing my alarm didn't go off. when i tried to turn on the phone with the home button, it wouldn't turn on. i tried the power button and even held it for over 20 seconds and if still wouldn't turn on. i had no clue what was happening so i just put it on charge and left it for about 20 minutes. then, i googled the issue and they said to hold lower volume button and power button for ten seconds. once i did that, it showed the large battery icon at 40%. i held the power button again to turn on the phone.

now, if you look at the picture i attached, it's something I've never seen before. the graph shows it went from 95 to 40 (instant vertical drop in graph) at some point overnight. i thought it went to 0 since the phone wasn't turning on the next day. have you guys ever seen this kind of situation? i know people have had battery drainage overnight but mine seem to happen instantly. 95 to 40 real quick. and if it really did drop to 40, why did the phone turn off? it should still be able to function at 40. please let me know if you have any insight on what caused this problem.

like i said, i got this over a day ago and it already gave me this problem that i never expected.

 

[belodion]

A vertical drop may indicate a faulty battery. Think dendrite.

Sent from mTalk

 

[galaxy android]

what should i do? my carrier says i cannot replace, return the device. should i wait a little more to see if it happens again before i take it to samsung? because the battery is perfect in terms of long lasting during the day. i just dont get why this happened overnight. I have attached a picture of what happened. As you can see, it went from 95 to 40 instantly, not overtime.

 

[belodion]

It could be a dendritic short. Keep screenshots as evidence, should a warranty return be necessary.

 

[nahoku]

Why won't the carrier replace the phone? Try another carrier store. Speak to someone else.

 

[galaxy android]

hi, what exactly is a dendritic short? Also, i've been hearing fast charging is not good for the battery life. Is it weird that I fast charged my phone from 40% to 95% and when I fell asleep it dropped instantly back to 4-% (like shown in picture)...is it a coincidence?

So far, this problem has not happened again and the battery is going strong. Do you think I should wait if it happens again or go straight to warranty now? Thanks