Galaxy Note 8 doing weird thing when charging

[Dannirobern]

I think my note 8 must've died, not sure how that happened considering I kept it on the charger all night and then used it for 15 minutes, before returning it to thee charger 4 hours later. So it shouldn't have been below 50%, at the least.

But when I picked it up a couple hours after plugging it in when I got home, I noticed the battery sign that pops up when you plug your android in when it's turned off was there, it's empty though and has a that "loading" circle but it's frozen (as in the circle is not rotating). The screen is flicking on and off, it'll pop on with the battery still empty and the loading sign for maybe 5 seconds, then go black for 5 seconds, then go back on. When I unplugged it and tried to turn it off it didn't get past the screen saying the device's name before it went black. Also didn't help when I tried to plug it in quickly before it went black.

What should I do? It's been doing this for a while. Should be at least a little charged by now.

 

[Mooncatt]

Sounds like the battery may be toast, to the point that it isn't supplying enough power to keep things going (every Android device I've used required a working battery to run even when plugged in). I haven't seen this specific symptom before, but it sounds like you keep this plugged in most of the time. Your mention of leaving it plugged in overnight, then charging it again after only 15 min use leads me to think this.

Lithium batteries don't like being held at a full charge or ran down to zero. It speeds up degradation, but many people like to keep their device plugged in so it's always at the ready with a full charge. Even if this wasn't the problem, it's best to reconsider your charging habits. Instead of charging it overnight, just make sure it has enough charge to make it through the night and charge it in the morning as needed. When it's full, unplug it and leave it unplugged until you get down to about 40% before charging it again.

 

[Dannirobern]

I took off the back with the intention of removing the battery but chickened out when I saw all the little screws. So I put it back on and then it worked. Maybe a hardware issue?


Ok, I'll try not to do that. But it's hard because it takes a long time to charge...

 

[Mooncatt]

Could have been something loose in there that you got set right again (for now?) to work. As for the charging, one good thing about lithium is there's no memory concerns. You can partial charge that thing all day long, never getting to 100% and it'll be fine. In fact, keeping or at less than a full charge is best for long term life if you want to be technical about it, even though it means charging more often.

When you say it takes a long time to charge, are you talking several hours or more? Most devices can fully charge in 1.5 hours or so. If you're going much longer than that, your USB cable could be going out, which is a common issue. I doubt it'd be related to the original problem, though.

 

[Rukbat]

Lithium batteries don't like being held at a full charge

I don't know where you heard that, but it's not true. They self-discharge faster if starting at a full charge, so if you're going to store the battery for a long time, it's better to start at about 50%, but in normal use you not only wait until the phone shows 100%, you wait another 30 minutes. The 100% indication includes the charger voltage - the battery is at about 98% at that point.Another 30 minutes will usually get into the top-off range, which is wwhere you want a charge to be. (After that you can leave it on the charger for months, and it won't hurt the battery - the charger will only feed current to the battery when the battery voltage drops a little.)

or ran down to zero.

Or even lower than 40%. Constantly bringing it down to 25% cuts the life by about 50%.

 

[Dannirobern]

Could have been something loose in there that you got set right again (for now?) to work. As for the charging, one good thing about lithium is there's no memory concerns. You can partial charge that thing all day long, never getting to 100% and it'll be fine. In fact, keeping or at less than a full charge is best for long term life if you want to be technical about it, even though it means charging more often.

When you say it takes a long time to charge, are you talking several hours or more? Most devices can fully charge in 1.5 hours or so. If you're going much longer than that, your USB cable could be going out, which is a common issue. I doubt it'd be related to the original problem, though.

No, I guess I'm just comparing it to my iPhone haha. I just got this cable though.

 

[Mooncatt]

I don't know where you heard that, but it's not true. They self-discharge faster if starting at a full charge, so if you're going to store the battery for a long time, it's better to start at about 50%, but in normal use you not only wait until the phone shows 100%, you wait another 30 minutes. The 100% indication includes the charger voltage - the battery is at about 98% at that point.Another 30 minutes will usually get into the top-off range, which is wwhere you want a charge to be. (After that you can leave it on the charger for months, and it won't hurt the battery - the charger will only feed current to the battery when the battery voltage drops a little.)

Or even lower than 40%. Constantly bringing it down to 25% cuts the life by about 50%.

It was one of the Battery University pages that talked about leaving a lithium battery fully charged. Charging to 100% for immediate use is fine. It's leaving it at a full charge, or "high charge" state as they put it, that harms battery life. They also added industrial use lithiums are charged to a slightly lower voltage because long term life is more important in those applications than short term capacity per charge.

That's also backed up by my research in the RC hobby where Lipo batteries are popular and many modelers are quite anal about taking care of them (you would be too when you consider you could ruin a $150 high voltage pack with one wrong move), posting stories about how mistakes like that put a battery out of commission. From my personal experience with phones, the OEM battery in my last one went bad in less than a year when I kept it plugged in almost all the time. I haven't had a problem with that since I started unplugging them once fully charged.