Note 4 suddenly turned off won't turn back on or charge

[TechDesserts]

So I've had my note 4 for a year and a half now and for the past few weeks it's been behaving strangely in terms of battery, sometimes when it reaches 5% or below and I plug it into the charger it immediately turns off as if the battery was 0% then the other strange thing is for a few times it won't charges past 88~90% even if I left it 4+ hours, but the main problem now is the other day I was playing a game and I remember looking at the battery before I clicked the game and it was at 66% 5 minutes into the game the screen went black and I assumed it just turned itself off since it was getting a little warm but when I tried to turn it back on a few minutes later it didn't respond, I took out the battery and put it back in and still no response, I then plugged in my charger but the led didn't light up either, I tried all of the power button + other buttons combination's possible but still nothing, I even got another battery (not an original one I believe) and it still won't turn on, the left side on the back (not the battery side) heats up now when I connect it to the charger for a few minutes when the new battery is in it but stays cold if the old battery is in.. what exactly is wrong with my phone ?

 

[natehoy]

the left side on the back (not the battery side) heats up now when I connect it to the charger for a few minutes when the new battery is in it but stays cold if the old battery is in

Please define "heats up". Do you mean "gets slightly warm", "effective hand warmer for chilly days", "mildly uncomfortable to hold", or "I'm going to go get a cast iron skillet and make an omelet!" ???

If you bought a really cheap battery off eBay, there is a distinct possibility that you have two bad batteries on your hands - one that has failed after a reasonable amount of use, and one that was built improperly.

Normally, I'd say it's possible that the new battery you bought was simply discharged and you need to plug it into a charger and leave it there, and that warming up is normal for a recovery charge of a discharged battery. However, if it's a cheapo battery, and especially if it is getting uncomfortably warm, I would recommend never giving that new battery power ever again and getting a refund if you can.

It is possible that something else has failed. However, "not charging to full" and "shutting off under heavy load when at reasonably high charge levels" are both obvious signs of a failed battery, and you were correct to replace the battery first.

I would (and have) replace your battery with a known-good one. Your carrier may still sell batteries for it (though maybe not in the store any more), or Amazon and others have both genuine Samsung batteries and good third party brands like Anker.

Some battery pairs (like Anker) even come with an external battery charger. That way, if the charge circuitry in your phone really has gone wrong, you can at least swap fully-charged batteries basically forever.